Surveillance outcomes in an Australian cohort undergoing piecemeal polypectomy for conventional adenomas and serrated lesions

Surveillance outcomes in an Australian cohort undergoing piecemeal polypectomy for conventional adenomas and serrated lesions | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Surveillance outcomes in an Australian cohort undergoing piecemeal polypectomy for conventional adenomas and serrated lesions Shweta Sharma, Patricia C Valery, Katherine Hanigan, Kimberley Ryan, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9350411/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 12 You are reading this latest preprint version Abstract Background and Aims: Current guidelines recommend early surveillance following piecemeal polypectomy due to recurrence risk; however, this contributes substantially to colonoscopy burden. We aimed to identify subgroups in which surveillance can be safely deferred beyond current guideline intervals in selected patients. Methods: We performed a two-centre retrospective study of consecutive patients undergoing first (SC1) and second (SC2) surveillance colonoscopy following piecemeal resection. Primary outcome was histological recurrence; secondary outcome was detection of additional high-risk polyps. Results: A total of 221 lesions, 130 conventional adenomas (CA) and 91 serrated lesions (SL) were resected piecemeal in 202 patients, with 76% removed using cold snare technique. Recurrence following cold resection occurred in 11% of CA ≥20 mm and 15% of CA <20 mm, while recurrence in SL was low (5% for <20 mm; 0% for ≥20 mm). Hot snare resection was predominantly used for larger CA (79% ≥20 mm) and was associated with a recurrence rate of 14%. Increasing age was associated with higher recurrence risk. At SC1, additional high-risk polyps were detected in 27% of patients, particularly following resection of larger index lesions. No advanced neoplasia was detected at SC2 in patients with serrated lesions without recurrence at SC1. Conclusions: Recurrence risk after piecemeal resection differs by polyp subtype and resection technique. Serrated lesions demonstrated low recurrence, suggesting surveillance intervals may be safely extended in selected patients with adequate index clearance. In contrast, conventional adenomas—even <20 mm—showed higher recurrence following cold resection, supporting the need for optimised resection techniques and continued early surveillance in this group. piecemeal surveillance recurrence cold snare polypectomy Figures Figure 1 Introduction Colorectal cancer (CRC) is a result of the stepwise malignant degeneration of precursor lesions. Timely and complete resection of these is an effective way to reduce CRC mortality. However, colonoscopy is invasive and resource intensive, thus, efforts should be directed to those most likely to benefit. Piecemeal polypectomy is becoming a greater part of clinical practice for various reasons. These include mounting support for the efficacy and safety of piecemeal polypectomy, enhanced recognition of sessile serrated lesions, as well as emphasis on colonoscopy quality with efforts to capture wider margins of normal mucosa and avoiding unintentional partial resection.( 1 – 4 ) Much of the literature guiding surveillance strategy following piecemeal resection relies on outcomes for larger, i.e. ≥20mm, conventional adenomas managed in expert centres. Factors such as operator technique and nature of the lesion, i.e. size, histology, morphology, and location are significant variables. Broadly, however, compared to en -bloc resection, recurrence with piecemeal polypectomy is significantly higher and has been quoted up to 20% versus about 3% for en -bloc resection.( 5 ) Current piecemeal surveillance strategies are conservative and place a heavy colonoscopy burden on patients and health services. Australian guidelines are consistent with international recommendation of first surveillance colonoscopy (SC1) at 6 months followed by a second surveillance colonoscopy (SC2) at 12–18 months. The recommended intervals are based off historical piecemeal hot snare resection data of ≥ 20mm conventional adenomas managed in expert centres. Currently endoscopic resection remains heterogenous with both cold and hot snare techniques as well as different recurrence rates for conventional adenomas versus serrated lesions. Consequently, follow-up advice is uniform and does not differentiate between polyp histology. Additionally, it does not specifically address lesions < 20mm in size. Conventional adenomas that are larger than 20mm in size are more likely to be higher risk lesions, harbour covert cancer, and be associated with synchronous advanced pathology.( 6 ) Sessile serrated lesions on the other hand are at a low risk of malignancy even when the size exceeds 10mm.( 7 ) The risk for these two pathologies may not be comparable and outcomes for smaller lesions are less clearly defined. Furthermore, this landscape has transformed in the last 5 years with margin thermal ablation has reduced recurrence to < 5% in polyps ≥ 20mm in expert centres and has called into question whether intensive surveillance is still necessary.( 8 ) This technique is being studied but not currently used post-cold-snare piecemeal polypectomy. The aim of the present study was to clarify whether extrapolating the evidence for piecemeal polypectomies for lesions ≥ 20mm in size to those < 20mm leads to over-surveillance. Outcomes were stratified for conventional adenomas versus sessile serrated lesions. We focussed on cold snare polypectomy as it was most common and at the time of this cohort, margin thermal ablation was not universally used after hot snare polypectomy. The primary outcome was the frequency of confirmed histological recurrence. As a secondary outcome, we assessed the prevalence of additional high-risk pre-malignant or cancerous lesions at first surveillance. We hoped to identify subgroups in which surveillance could safely be lengthened. Methods Study population The Royal Brisbane and Women’s Hospital (RBWH) and the Surgical Treatment and Rehabilitation Service (STARS) in Brisbane, Australia, have maintained a prospective database for every patient undergoing colonoscopy from 2018 onwards. The RBWH is a 929-bed quaternary and tertiary referral teaching hospital, and the STARS is a 182-bed tertiary public hospital specialising in rehabilitation, elective surgery and endoscopy. This is a retrospective observational cohort study which included consecutive patients aged ≥ 18. Data included all patients undergoing a complete colonoscopy over two years (2018–2019) with a repeat procedure within 3 years of the index colonoscopy. All patient medical records were reviewed to identify those who underwent a piecemeal polypectomy and to collect data on resection technique at index procedure and scar identification as well as additional polyp findings at surveillance. Exclusion criteria consisted of any of the polyps having prior attempted resection or if the procedure report specifically highlighted that the interval for follow-up colonoscopy was dictated by a reason other than piecemeal polyp surveillance, i.e. underlying diagnosis of inflammatory bowel disease, known or suspected polyposis syndromes, quality of bowel preparation, recent history of colorectal cancer, or high-risk lesions or concerns about incomplete resection. Lastly, if a patient underwent a repeat colonoscopy sooner than planned due to new onset of symptoms, these were excluded. The optimal management strategy for ≥ 20mm polyps resected with hot-snare piecemeal endoscopic mucosal resection followed by margin thermal ablation is well defined and recommended by international guidelines.( 9 ) This was not standard practice during the study period and therefore its use was sparse. Hence cases where hot-snare polypectomy with or without margin thermal ablation were excluded from the initial recurrence analysis. For the purposes of all subsequent analyses, i.e. assessment of additional polyps at surveillance as well as outcomes at SC2, all cases of piecemeal polypectomy were included. Ethics The study was approved by the Metro North Health Human Research Ethics Committee (EC00172). Procedure Index colonoscopy The procedures were performed by a specialist gastroenterologist or advanced trainee under direct supervision. Anaesthetist-directed sedation with a combination of fentanyl, midazolam, and propofol was employed in all cases. High definition colonoscopes (HQ190/EZ1500; Olympus, Tokyo, Japan) and carbon dioxide insufflation were used. Patients received split-dose bowel preparation. This is standard for both centres, and did not change during the period of this study. The solution used for submucosal fluid injection was a combination of succinylate gelatin (Gelofusine; B Braun, Bella Vista, Australia) and methylene blue or indigo carmine with or without the use of dilute adrenaline. Dedicated cold snares including Captivator™ Cold single-use snare. Alternatives included Captivator™ II cold and hot single-use snare (Boston Scientific, Marlborough, Mass, USA) or Snare Master Plus hybrid hot and cold snare (Olympus, Tokyo, Japan). The choice of snare, as well as decision to utilise a distal attachment cap, defect closure with clips, or snare-tip soft coagulation to defect margin, along with tattoo to locate the site at surveillance were at the proceduralist’s discretion. For hot polyopectomy, a microprocessor-controlled electrosurgical generator (Endocut effect 3, VIO 300D; ERBE Elektromedizin, Tübingen, Germany) with fractionated current was used in both centres. Where used, margin thermal ablation was performed using STSC (ERBE VIO 300D, SOFT COAG: 80W, Effect 4; ERBE, Tubingen, Germany). Surveillance colonoscopy The timing of first and second surveillance was determined by the proceduralist based on their confidence of complete resection, quality of prep, known residual polyps, as well as patient factors such as overall health and availability. The method of examination of polypectomy site, i.e. use of narrow-band imaging and magnification as well as decision for biopsy of the scar was proceduralist dependent. Lastly, management of recurrence followed by subsequent surveillance recommendation was also proceduralist determined. In the absence of recurrence, outcomes for second surveillance colonoscopy were reviewed. Data collection If the patient had both, conventional adenoma as well as a serrated lesions resected piecemeal at index procedure, only the larger lesion was included in analysis. To capture frequency of confident scar identification, all surveillance reports were manually reviewed for either written documentation or photo-documentation of the scar by a single researcher (SS). The ‘right colon’ was defined as including the caecum, ascending colon, hepatic flexure and transverse colon. The ‘left colon’ includes the descending colon, splenic flexure, sigmoid colon, descending colon and rectum. Those who were found to have any additional polyps on surveillance colonoscopies were divided in ‘low-risk’, ‘high-risk’, and ‘very-high risk’ groups. Those who were only found to have additional polyps that could safely wait for 5 years or longer for surveillance colonoscopy as per the Australian guidelines were considered ‘low risk’. ‘High-risk’ pathology on surveillance colonoscopy was defined as those who would be recommended to undergo a surveillance colonoscopy in 3 years’ time as per the Australian guidelines. Similarly, as per the national guidelines, those who would be recommended to return for surveillance in 1 year were defined as ‘very high-risk”.( 10 ) (Supplementary Table 1) Statistical analysis Analyses were conducted using StataNow/MP (Version 19.5; StataCorp LLC, College Station, TX). Univariable methods were used to describe the cohort and assess differences according lesion size (≥ 20mm vs < 20mm). Continuous and normally distributed variables were presented as mean ± SD, and differences between groups were analysed by one-way ANOVA. Non-normally distributed data are presented as median (range) and were analysed using the Kruskal-Wallis H test. Categorical data were presented as proportional percent and analysed using Pearson’s chi-squared (χ 2) or Fisher’s Exact test as denoted. Statistical significance was set at alpha = 0.05. Granular outcome analysis for high versus very-high risk additional polyps on surveillance could not be performed due to small numbers. Analysis of second surveillance data was no feasible due to rare event rate. Multivariable logistic regression analysis reported in terms of odds ratios (OR) with associated 95% confidence intervals (CI) was used to examine factors associated with: (i) recurrence among 168 polyps; and (ii) additional high or very high-risk polyps at first surveillance colonoscopy among 202 patients. First, unadjusted ORs are presented. Considering our understanding of the relationships among variables and their clinical relevance, as well as associations assessed first in univariate models and then in a multivariable analysis, we employed forward stepwise selection (p-value for addition < 0.20). Results In the years 2018 and 2019, 7,105 individuals underwent a colonoscopy at the two centres. The mean caecal intubation rate for the whole colonoscopy cohort through the study period was 97.8% with the mean adenoma detection rates of 53.1% and sessile serrated lesion detection rate of 15.5%. In 871 of these procedures surveillance within 3 years was recommended because of high-risk polyps identified at the index colonoscopy. Of these, a significant proportion, i.e. 202 (23%) were surveyed because a piecemeal polypectomy was performed (Fig. 1 ). Of the patients with polyps resected piecemeal, 119/202 (59%) had a dominant conventional adenoma and 83 (41%) had serrated lesions predominantly sessile serrated lesions (Supplementary Tables 2 and 3). 52% (105/202) of these had polyps that were < 20mm in size. Cold-snare polypectomy technique was utilised in 61% (73/119) of those with a conventional adenoma and 94% (78/83) with serrated lesions. Of the minority of polyps resected by hot snare piecemeal polypectomy, 42/53 (79%) were conventional adenomas ≥ 20mm. Histological recurrence at SC1 was 6/42 (15%) which likely reflects a low snare tip soft coagulation rate of 43%. Subsequent analysis is focussed on cases resected by cold snare polypectomy. Conventional adenomas resected by cold snare polypectomy The patient group were predominantly male with a mean age of 65.1 years (SD = 13.4). Of the 82 polyps were resected cold-piecemeal, 57% (47/82) were < 20mm in size (Table 1 ). The largest resected lesion measured 50mm and there was a right colon predominance in polyps less than 20mm in size. Table 1 Characteristics conventional adenomas in 73 patients with 82 polyps resected with cold snare. Patient characteristics (%) < 20mm ≥ 20mm N = 44 (60)* N = 29 (40)* p-value Age, mean (SD), years 63.7 (11.1) 67.2 (11.8) 0.19† Female, n (%) 14 (31.8) 13 (44.8) 0.26 Polyp characteristics N = 47 N = 35 Size median (IQR), mm 15 ( 12 – 15 ) 22 ( 20 – 30 ) Location , n (%) Right colon 43 (91) 28 (80) 0.19* Exact location 0.26* Rectum 0 (0) 2 ( 6 ) Sigmoid, descending colon, splenic flexure 4 ( 9 ) 5 ( 14 ) Transverse colon, hepatic flexure 8 ( 17 ) 8 ( 23 ) Ascending colon 18 (38) 13 (37) Caecum, IC valve, appendiceal orifice 17 (36) 7 ( 20 ) Histology 0.11* Tubular adenoma with low grade dysplasia (LGD) 32 (68) 26 (74) Tubular adenoma with high grade dysplasia (HGD) 5 ( 11 ) 1 ( 3 ) Tubulovillous adenoma with LGD 10 ( 21 ) 5 ( 14 ) Tubulovillous adenoma with HGD 0 (0) 3 ( 9 ) Polypectomy technique, n (%) Submucosal injection 30 (64) 28 (80) 0.11 Snare tip soft coagulation (STSC) post polypectomy 1 ( 2 ) 1 ( 3 ) 1.00* Clip placed 4 ( 9 ) 3 ( 9 ) 0.99 Site tattooed 1 ( 2 ) 5 ( 14 ) 0.079* Outcome at S1 Time from index colonoscopy to first surveillance, median (IQR), months 8.0 (6.0–12.0) 6.0 (4.0–7.0) < 0.001 ‡ Time to S1 < 6 months 9 ( 19 ) 14 (40) 0.038 Time to ≥ 6 months 38 (81) 21 (60) Confident scar identification 24 (51) 25 (71) 0.063 Suspected macroscopic recurrence 9 ( 19 ) 3 ( 9 ) 0.18 Biopsy/resection 16 ( 30 ) 32 (42) 0.19 Histological recurrence 7 ( 15 ) 4 ( 11 ) 0.65 SD, Standard deviation; N, frequency; Values are n (%) and Pearson’s chi-squared are reported unless otherwise defined; *Fishers exact test; †Two sample t test; ‡Wilcoxon rank-sum The median time to first surveillance was significantly less in the polyps that were ≥ 20mm in size with the median time being 6 months (IQR 4.0–7.0) compared to 8 months (IQR 6.0–12.0; p < 0.001) for those measuring less than 20mm. Confident scare identification was 71% in large polyps but only 51% in smaller polyps (p = 0.063). Histological recurrence at SC1 was demonstrated in 15% of conventional adenomas < 20mm. A lower, rate of histological recurrence at SC1 of 11% was demonstrated in ≥ 20mm conventional adenomas resected piecemeal using cold snare but this difference was not statistically significant (p = 0.65). Serrated lesions resected by cold snare polypectomy Patients with serrated lesions were younger than those with conventional adenomas (mean age 55.9 years (SD = 13.7 vs 65.1 years, SD = 11.4; p < 0.001) (Table 2 ). Of the 86 polyps resected with cold-snare polypectomy technique, 25 (29%) were ≥ 20mm. Maximum lesion size was 35mm with the smallest lesion resected cold-piecemeal measuring 6mm. Higher risk lesions, i.e. SSL-D and TSAs were infrequent with a total of 3 and 2 polyps respectively. Table 2 Characteristics of serrated lesions in 78 patients with 86 polyps resected using cold snare. Patient characteristics (%) < 20mm ≥ 20mm N = 55 (71)* N = 23 ( 29 ) * p-value Age, mean (SD), years 55.7 (14.3) 56.5 (12.4) 0.83† Sex, female, n (%) 40 (72.7) 16 (69.6) 0.78 Polyp characteristics N = 61 N = 25 Size median (IQR), mm 14 ( 10 – 15 ) 20 ( 20 – 25 ) Location, n (%) Right colon 51 (84) 25 (100) 0.32* Exact location 0.025* Rectum 1 ( 2 ) 0 (0) Sigmoid, descending colon, splenic flexure 9 ( 15 ) 0 (0) Transverse colon, hepatic flexure 14 ( 23 ) 5 ( 20 ) Ascending colon 21 (34) 17 (68) Caecum, IC valve, appendiceal orifice 16 ( 26 ) 3 ( 12 ) Histology , n (%) 0.26* Hyperplastic polyp 8 ( 13 ) 1 ( 4 ) Sessile serrated lesion 50 (82) 22 (88) Sessile serrated lesion with dysplasia 1 ( 2 ) 2 ( 8 ) Traditional serrated lesion 2 ( 3 ) 0 (0) Polypectomy technique Submucosal injection 47 (77) 19 (76) 0.92 Snare tip soft coagulation post polypectomy 1 ( 2 ) 0(0) 1.00* Clip(s) placed 5 ( 8 ) 1 ( 4 ) 0.67 Site tattooed 2 ( 3 ) 0 (0) 1.00* Outcome at S1 Time from index procedure to first surveillance, median (IQR), months 9.0 (6.0–13.0) 6.0 (5.0–8.0) < 0.001 ‡ Time to S1 < 6 months 4 ( 7 ) 7 ( 28 ) 0.012 Time to S1 ≥ 6 months 57 (93) 18 (72) Confident scar identification 18 ( 30 ) 17 (57) 0.012 Suspected macroscopic recurrence 4 ( 7 ) 2 ( 7 ) 1.00 Biopsy/resection 7 ( 11 ) 8 ( 27 ) 0.066 Histological recurrence 3 ( 5 ) 0 (0) 0.55 SD, Standard deviation; N, frequency; Values are n (%) and Pearson’s chi-squared are reported unless otherwise defined; *Fishers exact test; †Two sample t test; ‡Wilcoxon rank-sum Time to first surveillance was significantly greater in patients with serrated polyps that were less than 20mm in size with a median of 9 months (IQR 6.0–13.0) versus 6 months (IQR 5.0–8.0; p < 0.001) in polyps greater than 20mm. Confident scar identification was less common than when conventional adenomas had been resected piecemeal and scar was identified at SC1 in only 30% (18/61) of cases with a serrated polyp < 20mm resected piecemeal by cold snare polypectomy vs 57% (17/25 polyp ≥ 20mm (p = 0.012). Histological recurrence at SC1 was not common after piecemeal polypectomy of serrated lesions (3.4%, 3/86 polyps), with difference according to lesion size (3/61 in polyps < 20mm vs none in ≥ 20mm; p = 1.00). Of these 3 cases, one in the ascending colon may have been related to failure to use submucosal injection to further demarcate the lesion borders and two are likely to be associated with their technically difficult location in the appendiceal orifice which is well known to be a challenging location with high risk of recurrence. Factors associated with histological recurrence at SC1 after cold-snare polypectomy The combined polyp recurrence rate at first surveillance was 8.3% and was more common in conventional adenomas (Table 3 ). Those with polyp recurrence were 11.1 years older (mean 71.0 years [[SD = 9.9] vs 59.9 years [SD = 13.2]; p = 0.003). On univariate analysis, recurrence in the conventional adenoma group was 4.3-fold higher (OR = 4.29, 95% CI 1.15–15.97) as compared to the serrated lesion group (p = 0.030) (Table 4 ). Neither polyp location, nor size were statistically significant determinants for recurrence. The only procedural factor significantly associated with recurrence was tattooing. This was associated with an 8.1-fold increased risk of recurrence (95% CI 1.71–38.55; 0.008). Additionally, less recurrence was found in patients brought back for SC1 later (OR = 0.79, 95%CI 0.65–0.98; p = 0.03) although this difference disappeared on multivariable analysis (Table 4 ). Older age was the only factor significantly associated with recurrence (adjusted OR = 2.06, 95%CI 1.09–3.89; p = 0.025) on multivariate analysis. Table 3 Factors associated with per-polyp recurrence at first surveillance colonoscopy among 168 polyps resected with cold-snare technique. Age, mean (SD), years No recurrence N = 154 (91.7%)* Recurrence N = 14 (8.3%)* p-value 59.9 (13.3) 71.0 (9.9) 0.003 Female, n (%) 85 (55.2) 8 (57.1) 0.89 Polyp histology Serrated 83 (53.9) 3 (21.4) 0.025* Conventional adenoma 71 (46.1) 11 (79.0) Polyp location (right vs left) Right colon 133 (86.4) 14 (100.0) 0.22* Left colon 21 (13.6) 0 (0.0) Polyp size (mm), median (IQR) 15.0 (12.0–20.0) 15.0 (12.0–20.0) 0.92 Polyp size < 20mm 98 (63.6) 10 (71.4) 0.56 ≥ 20mm 56 (36.4) 4 (28.6) Submucosal injection 114 (74.0) 10 (71.4) 0.76* Snare tip soft coagulation post polypectomy 3 (1.9) 0 (0) 1.0* Clip(s) placed 11 (7.1) 2 (14.3) 0.34 Site tattooed 5 (3.2) 3 (21.4) 0.020* Time from index colonoscopy (months) to S1, median (IQR) 7.0 (6.0–12.0) 6.0 (5.0–6.0) 0.015 SD, Standard deviation; N, frequency; Values are n (%) unless otherwise defined; *Fishers exact test Table 4 Results from logistic regression analysis assessing factors associated with recurrence among 168 polyps with cold-snare technique. Age in decades OR (95% CI) p-value Adjusted OR (95%CI)* p-value 2.37 (1.31–4.29) 0.004 2.06 (1.09–3.89) 0.025 Sex (female vs male) 1.08 (0.36–3.27) 0.89 N/S Polyp histology (conventional adenoma vs serrated) 4.29 (1.15–15.97) 0.03 2.85 (0.67–12.16) 0.16 Polyp location (right vs left) 1.00 (omitted) N/S Size (≥ 20mm vs < 20mm) 0.70 (0.21–2.34) 0.56 0.29 (0.07–1.28) 0.10 Exact size 1.03 (0.97–1.10) 0.38 N/S Submucosal injection 0.88 (0.26–2.95) 0.83 N/S Snare tip soft coagulation post polypectomy 1.00 (omitted) N/S Clip(s) placed 2.17 (0.43–10.92) 0.35 N/S Site tattooed 8.13 (1.71–38.55) 0.008 5.96 (0.96–37.13) 0.06 Time from index colonoscopy (months), median (IQR) 0.79 (0.65–0.98) 0.028 0.68 (0.17–2.82) 0.60 Note: Bold values indicate statistical significance (p < 0.05); Not selected (N/S); *Multivariable logistic regression model included histology, age and size (≥ 20mm vs < 20mm), procedures clip and tattooing, and time from time from index colonoscopy Additional polyps at SC1 after cold or hot-snare polypectomy 75 (34%) of the total study population who underwent both cold and hot-snare polypectomy did not have any additional polyps at SC1. Low risk polyps were found in 87 (39%) and high-risk polyps and very high-risk polyps in 26 (12%) and 33 (15%) respectively. A reason for early surveillance is the detection and removal of high or very high-risk polyps so factors which may predict their occurrence were sought. The fifty-four patients (26.6%) who had additional high or very high-risk polyps at first surveillance colonoscopy were 4 years older (67.0 years, IQR 57.0–73.0) than those who had low risk or no additional polyps(64.8 years, SD = 12.6 vs 60.7 years (SD = 13.0; p = 0.046), and had larger a polyp size (20.0mmm, IQR 15.0–30.0) vs 18.0mm, IQR 14.0–25.0), respectively; p = 0.022) (Supplementary Table 4). In univariate analysis, patients with conventional adenomas appeared to have more high-risk polyps in patients with conventional adenomas, but this did not reach statistical significance (p = 0.103). Older age (OR = 1.30, 95% CI (I.00-1.68) and larger polyp size (OR = 1.03, 95% CI (1.01–1.05) increased the risk of having additional high or very high-risk polyps at first surveillance colonoscopy. In multivariable analysis including histology, age and polyp exact size, only polyp size was associated with having additional high or very high-risk polyps at first surveillance colonoscopy (adj-OR = 1.03, 95% CI 1.00-1.05; p = 0.035). SC2 outcomes post hot and cold-snare polypectomy After exclusion of the 21 patients with recurrence at SC1, follow-up outcomes for the remaining 181 who had undergone either cold or hot-snare polypectomy were reviewed. Of these, 124 (69%) underwent SC2. 76 of them had piecemeal resection of a dominant conventional adenoma at index procedure and 48 had an initial serrated lesion (Supplementary Table 5). The numbers are too small to allow for formal statistical comparisons by lesion size. Histological recurrence was confirmed in one case of < 20mm serrated polyp where the scar was biopsied, and no recurrence confirmed at SC1. No recurrence was seen in < 20mm conventional adenoma subgroup but there were a total 4 cases of recurrence in those with a ≥ 20mm conventional adenoma resected piecemeal at index colonoscopy. Scars had been reviewed at SC1 in all four of these cases and biopsies were performed in two cases without histological recurrence at SC1. No cancers were identified on SC1 and SC2. Polyp recurrence was endoscopically treated in all cases with the polypectomy technique at the endoscopist’s discretion. Discussion Our study conducted in the context of contemporary, high quality colonoscopy practice demonstrates that surveillance after piecemeal polypectomy contributes significantly to the overall burden of surveillance. The convenience and safety of piecemeal polypectomy especially by cold snare technique needs to be balanced with the need for increased follow-up frequency. Resource conservation and mitigating delays in access to colonoscopy by attempting to lengthen follow-up intervals is a topic of great interest.( 11 – 13 ) Surveillance intervals can only safely be lengthened, however, by either identifying those at lower risk or reducing post-polypectomy recurrence by improving procedural quality, i.e. reducing the incidence of recurrence at polypectomy site as well as identifying residual high-risk polyps at the time of index colonoscopy. The frequency of incomplete resection and recurrence varies in the literature.( 5 , 11 , 14 – 17 ) Additionally, studies that provide comparison of outcomes from polypectomies less and greater than 20mm in size are sparse. One contributor to recurrence is polypectomy technique. The evidence surrounding the application of cold snare resection of polyps < 20mm has been steadily increasing.( 18 ) This technique has comparable efficacy to hot-snare resection for polyps measuring < 10mm.( 9 , 19 ) For medium sized polyps measuring 10-19mm, however, the literature is less clear with variable reported rates of recurrence after cold snare piecemeal polypectomy.( 1 , 4 , 20 , 21 ) It is thought to be least appropriate for the resection of larger adenomas ≥ 20mm due to significantly higher rates of recurrence with cold polypectomy.( 17 , 22 ) Currently, international guidelines recommend consideration of conventional, i.e. diathermy based EMR for ≥ 20mm non-pedunculated adenomatous polyps.( 9 ) Furthermore, margin thermal ablation to the defect has been shown to dramatically reduce the incidence of recurrence at surveillance compared to conventional resection technique is now recommended as standard practice after hot snare piecemeal polypectomy.( 9 ) This technique is now a firmly established standard of care. Hence, the subgroup with hot-snare polypectomy with or without STSC were not the focus of our analysis The primary outcome of this study was assessment of recurrence rates. In those with cold piecemeal resection, we found no significant difference in recurrence with smaller conventional adenomas compared to large adenomas. This was an unexpected finding, and our results may be explained by proceduralist bias, i.e., larger conventional adenomas that are technically more difficult to resect or those with higher risk of recurrence based on optical assessment may have been more likely to be removed using electrocautery. It is worth noting that in the present study, the recurrence rate of conventional adenomas < 20mm resected by cold snare polypectomy remains clinically significant at 15%. justifying SC1 at 6 months regardless of adenoma size unless improvement in techniques can reduce recurrence. Apart from use of submucosal injection, overlapping tissue and wide margin resection, few auxiliary techniques have been shown to improve recurrence rates post cold resection. The technique of cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST) has been employed in cases with non-lifting large non-pedunculated polyps as well as in treating recurrence at surveillance.( 23 ) This demonstrates the role of thermal ablation as a safe and effective adjunct to reduce recurrence outside of conventional EMR. This raises the question of thermal ablation post-cold-polypectomy but this has not been formally evaluated or validated. The only procedural technique with a trend towards higher risk of recurrence was tattoo placement. This could be explained by the possibility that proceduralists were more likely to place a tattoo when additional macroscopic predictors of recurrence risk are macroscopically evident or alternatively when their confidence in complete resection was lower.( 24 ) This trend was also noted where risk of recurrence is lower in those who underwent later first surveillance. Given the small numbers, chance cannot be ruled out, however, this may indicate the value of proceduralist confidence in complete resection and risk identification. Mirroring the trend in the literature for serrated lesions, recurrence rates were very significantly lower in this subgroup as compared to conventional adenomas.( 17 , 25 ) Owing to high rates of complete resection, routine use of this method for polyps < 20mm is accepted. Additionally, our results support the extension of this technique to large sessile polyps ≥ 20mm.( 3 , 17 , 26 – 28 ) Typically, size is thought to be an important factor where larger lesions are more likely to be associated with recurrence. Like conventional adenomas, we found paradoxically the only 3 cases of recurrence in polyps measuring < 20mm and all 3 of the lesions had specific factors, i.e. lack of utilisation of submucosal injection as well as location at the appendiceal orifice, which may have contributed to incomplete resection.( 29 , 30 ) An important consideration when assessing recurrence is accurately identifying the location of previous polypectomy. Although the reliability of careful optical assessment of post-polypectomy scar has been demonstrated and routine biopsies are not necessary, small polypectomy scars can be difficult to confidently locate.( 31 , 32 ) Literature comparing frequency of scar identification post cold polypectomy for smaller polyps is sparse. Like Mass et al ., we found that scar identification and documentation is infrequent in everyday practice.( 13 ) Scar identification could be aided by uncommonly employed techniques such as tattoo, clips, cautery or hot snare for smaller lesions however all these techniques come at a cost and add more time to the procedure Our secondary outcome was to assess additional lesions at surveillance. We found a clinically significant rate of ‘very high-risk lesions’ on surveillance in an endoscopy unit with high performance on validated quality indicators. The prevalence of very high-risk polyps at SC1 was 15%. Overall, those at highest risk were more likely to be older and have a larger polyp resected. Age and polyp size have been previously shown to be a potential predictors of the risk of additional polyps although it is disappointing that the prevalence of very high risk polyps should be so high 6 months after a high quality colonoscopy.( 33 ) While the strength of this study is the real-world nature of the outcomes, the heterogeneity in practice from multiple operators and retrospective nature of the study is a limitation. Given that decisions were dictated by the individual endoscopist, including interval for returning for surveillance, the potential for bias exists. Furthermore, the cohort size limits evaluation of subgroups that might benefit from lengthening surveillance interval, and our findings should be interpreted with caution as there may have been differences that the study did not detect. Although serrated lesions have a low risk of recurrence, the finding of high-risk additional polyps is not negligible and should be an important consideration. The recurrence rates for conventional adenomas were reasonably high and not dependent on size. For hot snare piecemeal polypectomy, this is likely to change as margin thermal ablation post polypectomy becomes the universal standard of care. Whether there is a role for ablation post-cold-snare polypectomy as a simple auxiliary technique to eradicate the possibility of microscopic polyp remnants despite overlapping snare and side resection remains an unexplored concept. This real-world study shows that cold piecemeal polypectomy even for smaller lesions is a significant contributor to the burden of surveillance. Most of the cases are performed by cold snare technique which enhances safety but limits adoption of adjuvant techniques to lower recurrence and chances of identifying previous polypectomy location. Additionally, this is associated with a clinically significant risk of recurrence in conventional adenomas even < 20mm. Especially while the optimal approach for medium-sized (10-19mm) polyps is still debated, our findings support the current conservative approach with the recommendation of first surveillance at 6 months to ensure early detection and management. If delayed surveillance were to be considered, younger patients with index serrated lesions would be the most suitable candidates to be considered however further prospective studies are required. Conclusions Recurrence risk after piecemeal resection differs by polyp subtype and resection technique. Serrated lesions demonstrated low recurrence, suggesting surveillance intervals may be safely extended in selected patients with adequate index clearance. In contrast, conventional adenomas—even < 20 mm—showed higher recurrence following cold resection, supporting the need for optimised resection techniques and continued early surveillance in this group. Declarations Conflict of interest: The authors declare no conflicts. Author Contribution SS and BL conceptualised the study. Initial data was synthesised by KH and subsequently analysed by PV. SS, PV and BL interpreted the data. SS drafted the initial article with critical revisions by SS, MA, PV and BL. All authors approved the final version of the manuscript. Data Availability The Royal Brisbane and Women’s Hospital (RBWH) and Surgical Treatment and Rehabilitation Service (STARS) maintain a prospective data base (Colonoscopy Outcomes Registry) of every patient who has undergone colonoscopy from February 2018 onwards. Post procedure and subsequent availability of histology results, surveillance nurses dedicated to this task manually enter patient demographics and procedure details, including bowel preparation quality, completion of procedure as well as polyp numbers, size, and location. Lastly, the histology findings, procedure details and subsequent surveillance recommendations are all entered in a standardized format on a secure web application (REDCap). References Mangira D, Raftopoulos S, Vogrin S, Hartley I, Mack A, Gazelakis K, et al. Effectiveness and safety of cold snare polypectomy and cold endoscopic mucosal resection for nonpedunculated colorectal polyps of 10–19 mm: a multicenter observational cohort study. Endoscopy. 2023. Tutticci NJ, Hewett DG. Cold EMR of large sessile serrated polyps at colonoscopy (with video). Gastrointest Endosc. 2018;87(3):837–42. Van Hattem WA, Shahidi N, Vosko S, Hartley I, Britto K, Sidhu M, et al. Piecemeal cold snare polypectomy versus conventional endoscopic mucosal resection for large sessile serrated lesions: a retrospective comparison across two successive periods. Gut. 2021;70(9):1691–7. Rex DK, Anderson JC, Pohl H, Lahr RE, Judd S, Antaki F, et al. Cold versus hot snare resection with or without submucosal injection of 6-to 15-mm colorectal polyps: a randomized controlled trial. Gastrointestinal Endoscopy. 2022;96(2):330–8. Belderbos TD, Leenders M, Moons LM, Siersema PD. Local recurrence after endoscopic mucosal resection of nonpedunculated colorectal lesions: systematic review and meta-analysis. Endoscopy. 2014;46(5):388–402. Burgess NG, Hourigan LF, Zanati SA, Brown GJ, Singh R, Williams SJ, et al. Risk Stratification for Covert Invasive Cancer Among Patients Referred for Colonic Endoscopic Mucosal Resection: A Large Multicenter Cohort. Gastroenterology. 2017;153(3):732 – 42.e1. Burgess NG, Pellise M, Nanda KS, Hourigan LF, Zanati SA, Brown GJ, et al. Clinical and endoscopic predictors of cytological dysplasia or cancer in a prospective multicentre study of large sessile serrated adenomas/polyps. Gut. 2016;65(3):437–46. O’Sullivan T, Mandarino FV, Gauci JL, Whitfield AM, Kerrison C, Elhindi J, et al. Impact of margin thermal ablation after endoscopic mucosal resection of large (≥ 20 mm) non-pedunculated colonic polyps on long-term recurrence. Gut. 2025;74(1):67–74. Ferlitsch M, Hassan C, Bisschops R, Bhandari P, Dinis-Ribeiro M, Risio M, et al. Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline–update 2024. Endoscopy. 2024;56(07):516–45. Barclay K, Leggett, B, Macrae, F, Bourke, M, Ee H, Cancer Council Australia Surveillance Colonoscopy Guidelines Working Party Cancer Council Australia Surveillance Colonoscopy Guidelines Working Party. Clinical question:What should be the surveillance colonoscopy for patients with adenoma multiplicity with or without polyposis syndrome? Sydney [cited 2023 June 09]. Available from: https://wiki.cancer.org.au/australia/Clinical_question:What_ should_be_the_surveillance_colonoscopy_for_patients_with_ adenoma_multiplicity_with_or_without_polyposis_syndrome%3F . Bobay MC, Lahr RE, Shultz J, Vemulapalli KC, Guardiola JJ, Rex DK. Safety of first surveillance colonoscopy at 12 months after piecemeal EMR of large nonpedunculated colorectal lesions. Gastrointestinal Endoscopy. 2024;100(5):905–13. Gomez Cifuentes JD, Berger S, Caskey K, Jove A, Sealock R, Hair C, et al. New model to predict recurrence after endoscopic mucosal resection of non-pedunculated colonic polyps ≥ 20 mm. Digestive Diseases and Sciences. 2023;68(10):3935–42. Maas MH, Hazewinkel Y, Droste JSTS, Schrauwen RW, Tan AC, Koehestanie P, et al. Recurrence after piecemeal hot-snare endoscopic mucosal resection of 10–20-mm nonpedunculated colorectal polyps: a multicenter cohort study. Endoscopy. 2025. Belderbos TD, Leenders M, Moons LM, Siersema PD. Local recurrence after endoscopic mucosal resection of nonpedunculated colorectal lesions: systematic review and meta-analysis. Endoscopy. 2014;46(05):388–402. Moss A, Williams SJ, Hourigan LF, Brown G, Tam W, Singh R, et al. Long-term adenoma recurrence following wide-field endoscopic mucosal resection (WF-EMR) for advanced colonic mucosal neoplasia is infrequent: results and risk factors in 1000 cases from the Australian Colonic EMR (ACE) study. Gut. 2015;64(1):57–65. Klein A, Tate DJ, Jayasekeran V, Hourigan L, Singh R, Brown G, et al. Thermal ablation of mucosal defect margins reduces adenoma recurrence after colonic endoscopic mucosal resection. Gastroenterology. 2019;156(3):604–13. e3. Pohl H, Rex DK, Barber J, Moyer MT, Elmunzer BJ, Rastogi A, et al. Cold snare endoscopic resection for large colon polyps: a randomised trial. Gut. 2025;74(11):1804–13. Guardiola JJ, Anderson JC, Kaltenbach T, Pohl H, Rex DK. Cold snare resection in the colorectum: when to choose it, when to avoid it, and how to do it. Clinical Gastroenterology and Hepatology. 2025;23(4):507–15. e6. Kaltenbach T, Anderson JC, Burke CA, Dominitz JA, Gupta S, Lieberman D, et al. Endoscopic removal of colorectal lesions: recommendations by the US Multi-Society Task Force on Colorectal Cancer. Official journal of the American College of Gastroenterology| ACG. 2020;115(3):435–64. von Renteln D, Djinbachian R, Benard F, Barkun AN, Bouin M, Bouchard S, et al. Incomplete resection of colorectal polyps of 4–20 mm in size when using a cold snare, and its associated factors. Endoscopy. 2023;55(10):929–37. O’Sullivan T, Cronin O, van Hattem WA, Mandarino FV, Gauci JL, Kerrison C, et al. Cold versus hot snare endoscopic mucosal resection for large (≥ 15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial. Gut. 2024;73(11):1823–30. Williams TJ, Mickenbecker M, Smith N, Bhasker V, Rubtsov D, Jones A, et al. Efficacy of cold piecemeal EMR of medium to large adenomas compared with sessile serrated lesions. Gastrointestinal Endoscopy. 2025;101(1):178–83. Mandarino FV, O'Sullivan T, Gauci JL, Kerrison C, Whitfield A, Lam B, et al. Impact of margin thermal ablation after cold-forceps avulsion with snare-tip soft coagulation for nonlifting large nonpedunculated colorectal polyps. Endoscopy. 2025. Medina-Prado L, Hassan C, Dekker E, Bisschops R, Alfieri S, Bhandari P, et al. When and how to use endoscopic tattooing in the colon: an international Delphi agreement. Clinical Gastroenterology and Hepatology. 2021;19(5):1038–50. Abdallah M, Ahmed K, Abbas D, Mohamed MF, Suryawanshi G, Mcdonald N, et al. Cold snare endoscopic mucosal resection for colon polyps: a systematic review and meta-analysis. Endoscopy. 2023;55(12):1083–94. Rex DK, Dekker E. How we resect colorectal polyps < 20 mm in size. Endoscopy. 2018;50(11):1112–5. Chandrasekar VT, Spadaccini M, Aziz M, Maselli R, Hassan S, Fuccio L, et al. Cold snare endoscopic resection of nonpedunculated colorectal polyps larger than 10 mm: a systematic review and pooled-analysis. Gastrointestinal endoscopy. 2019;89(5):929–36. e3. Mangira D, Cameron K, Simons K, Zanati S, LaNauze R, Raftopoulos S, et al. Cold snare piecemeal endoscopic mucosal resection of large sessile colonic polyps ≥20 mm (with video). Gastrointestinal endoscopy. 2020. Zhang M-Y, Yao J-J, Pan S-X, Hou W-W, Wei X, Zhao X-L, et al. Sessile serrated lesions involving the appendiceal orifice: Endoscopic diagnosis and treatment. World Journal of Gastrointestinal Endoscopy. 2025;17(10):110417. Song EM, Yang H-J, Lee HJ, Lee HS, Cha JM, Kim HG, et al. Endoscopic resection of cecal polyps involving the appendiceal orifice: a KASID multicenter study. Digestive Diseases and Sciences. 2017;62(11):3138–48. Meulen LW, Bogie RM, Siersema PD, Winkens B, Vlug MS, Wolfhagen FH, et al. Optical assessment of scars after endoscopic mucosal resection of large colorectal polyps in a multicenter, community hospital setting: is routine biopsy still necessary? Endoscopy. 2025;57(06):620–8. Kandel P, Brand EC, Pelt J, Ball CT, Chen W-C, Bouras EP, et al. Endoscopic scar assessment after colorectal endoscopic mucosal resection scars: when is biopsy necessary (EMR Scar Assessment Project for Endoscope (ESCAPE) trial). Gut. 2019;68(9):1633–41. Suresh S, Zhang J, Ahmed A, Ghanimeh MA, Elbanna A, Kaur R, et al. Risk factors associated with adenoma recurrence following cold snare endoscopic mucosal resection of polyps ≥ 20 mm: a retrospective chart review. Endoscopy International Open. 2021;9(06):E867-E73. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9350411","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":621914365,"identity":"3694572b-565f-4f04-8f38-0b6e01dcb8c0","order_by":0,"name":"Shweta Sharma","email":"data:image/png;base64,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","orcid":"","institution":"University of Queensland","correspondingAuthor":true,"prefix":"","firstName":"Shweta","middleName":"","lastName":"Sharma","suffix":""},{"id":621914366,"identity":"5286e739-0024-468c-af0c-19dc961fd47c","order_by":1,"name":"Patricia C Valery","email":"","orcid":"","institution":"QIMR Berghofer Medical Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Patricia","middleName":"C","lastName":"Valery","suffix":""},{"id":621914367,"identity":"aeb4bdd9-992f-4f98-969b-2d190644ea07","order_by":2,"name":"Katherine Hanigan","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Katherine","middleName":"","lastName":"Hanigan","suffix":""},{"id":621914368,"identity":"c9b51350-c5f8-447f-9c9a-22fa86d8bdea","order_by":3,"name":"Kimberley Ryan","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kimberley","middleName":"","lastName":"Ryan","suffix":""},{"id":621914369,"identity":"719d2318-42db-4a13-9cea-77ba15626e26","order_by":4,"name":"Mark Appleyard","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Mark","middleName":"","lastName":"Appleyard","suffix":""},{"id":621914370,"identity":"2392b4a9-fcf3-4f12-ade2-6ff41cfe366c","order_by":5,"name":"Nicholas Tutticci","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Nicholas","middleName":"","lastName":"Tutticci","suffix":""},{"id":621914371,"identity":"140a48bc-a63e-4464-91c4-7cd7162b1859","order_by":6,"name":"Timothy O’Sullivan","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Timothy","middleName":"","lastName":"O’Sullivan","suffix":""},{"id":621914372,"identity":"99697c88-f44f-491e-85b5-07895b18c8ad","order_by":7,"name":"Barbara Leggett","email":"","orcid":"","institution":"Royal Brisbane and Women’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Barbara","middleName":"","lastName":"Leggett","suffix":""}],"badges":[],"createdAt":"2026-04-08 02:10:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9350411/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9350411/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107484783,"identity":"1135d90d-6474-4dc8-9fdc-fe11187a47c2","added_by":"auto","created_at":"2026-04-22 02:32:57","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":54606,"visible":true,"origin":"","legend":"\u003cp\u003eA piecemeal polypectomy\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9350411/v1/21612259902dfa37756ec162.png"},{"id":107487149,"identity":"0b970a32-1ee2-496b-a956-8de7e2e33ed6","added_by":"auto","created_at":"2026-04-22 02:39:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":752632,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9350411/v1/ff5ac625-3106-4d34-b024-0b7ad7b835f3.pdf"},{"id":107257718,"identity":"1e61b83c-16e7-4749-abe7-c3a595efc621","added_by":"auto","created_at":"2026-04-19 12:33:08","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":27403,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTables.docx","url":"https://assets-eu.researchsquare.com/files/rs-9350411/v1/a5a5e123cd84c0801dd9bf04.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Surveillance outcomes in an Australian cohort undergoing piecemeal polypectomy for conventional adenomas and serrated lesions","fulltext":[{"header":"Introduction","content":"\u003cp\u003eColorectal cancer (CRC) is a result of the stepwise malignant degeneration of precursor lesions. Timely and complete resection of these is an effective way to reduce CRC mortality. However, colonoscopy is invasive and resource intensive, thus, efforts should be directed to those most likely to benefit. Piecemeal polypectomy is becoming a greater part of clinical practice for various reasons. These include mounting support for the efficacy and safety of piecemeal polypectomy, enhanced recognition of sessile serrated lesions, as well as emphasis on colonoscopy quality with efforts to capture wider margins of normal mucosa and avoiding unintentional partial resection.(\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eMuch of the literature guiding surveillance strategy following piecemeal resection relies on outcomes for larger, i.e. \u0026ge;20mm, conventional adenomas managed in expert centres. Factors such as operator technique and nature of the lesion, i.e. size, histology, morphology, and location are significant variables. Broadly, however, compared to \u003cem\u003een\u003c/em\u003e-bloc resection, recurrence with piecemeal polypectomy is significantly higher and has been quoted up to 20% versus about 3% for \u003cem\u003een\u003c/em\u003e-bloc resection.(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) Current piecemeal surveillance strategies are conservative and place a heavy colonoscopy burden on patients and health services.\u003c/p\u003e \u003cp\u003eAustralian guidelines are consistent with international recommendation of first surveillance colonoscopy (SC1) at 6 months followed by a second surveillance colonoscopy (SC2) at 12\u0026ndash;18 months. The recommended intervals are based off historical piecemeal hot snare resection data of \u0026ge;\u0026thinsp;20mm conventional adenomas managed in expert centres. Currently endoscopic resection remains heterogenous with both cold and hot snare techniques as well as different recurrence rates for conventional adenomas versus serrated lesions. Consequently, follow-up advice is uniform and does not differentiate between polyp histology. Additionally, it does not specifically address lesions \u0026lt;\u0026thinsp;20mm in size.\u003c/p\u003e \u003cp\u003eConventional adenomas that are larger than 20mm in size are more likely to be higher risk lesions, harbour covert cancer, and be associated with synchronous advanced pathology.(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e) Sessile serrated lesions on the other hand are at a low risk of malignancy even when the size exceeds 10mm.(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) The risk for these two pathologies may not be comparable and outcomes for smaller lesions are less clearly defined. Furthermore, this landscape has transformed in the last 5 years with margin thermal ablation has reduced recurrence to \u0026lt;\u0026thinsp;5% in polyps \u0026ge;\u0026thinsp;20mm in expert centres and has called into question whether intensive surveillance is still necessary.(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) This technique is being studied but not currently used post-cold-snare piecemeal polypectomy.\u003c/p\u003e \u003cp\u003eThe aim of the present study was to clarify whether extrapolating the evidence for piecemeal polypectomies for lesions \u0026ge;\u0026thinsp;20mm in size to those \u0026lt;\u0026thinsp;20mm leads to over-surveillance. Outcomes were stratified for conventional adenomas versus sessile serrated lesions. We focussed on cold snare polypectomy as it was most common and at the time of this cohort, margin thermal ablation was not universally used after hot snare polypectomy. The primary outcome was the frequency of confirmed histological recurrence. As a secondary outcome, we assessed the prevalence of additional high-risk pre-malignant or cancerous lesions at first surveillance. We hoped to identify subgroups in which surveillance could safely be lengthened.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eStudy population\u003c/p\u003e \u003cp\u003eThe Royal Brisbane and Women\u0026rsquo;s Hospital (RBWH) and the Surgical Treatment and Rehabilitation Service (STARS) in Brisbane, Australia, have maintained a prospective database for every patient undergoing colonoscopy from 2018 onwards. The RBWH is a 929-bed quaternary and tertiary referral teaching hospital, and the STARS is a 182-bed tertiary public hospital specialising in rehabilitation, elective surgery and endoscopy. This is a retrospective observational cohort study which included consecutive patients aged\u0026thinsp;\u0026ge;\u0026thinsp;18. Data included all patients undergoing a complete colonoscopy over two years (2018\u0026ndash;2019) with a repeat procedure within 3 years of the index colonoscopy. All patient medical records were reviewed to identify those who underwent a piecemeal polypectomy and to collect data on resection technique at index procedure and scar identification as well as additional polyp findings at surveillance.\u003c/p\u003e \u003cp\u003eExclusion criteria consisted of any of the polyps having prior attempted resection or if the procedure report specifically highlighted that the interval for follow-up colonoscopy was dictated by a reason other than piecemeal polyp surveillance, i.e. underlying diagnosis of inflammatory bowel disease, known or suspected polyposis syndromes, quality of bowel preparation, recent history of colorectal cancer, or high-risk lesions or concerns about incomplete resection. Lastly, if a patient underwent a repeat colonoscopy sooner than planned due to new onset of symptoms, these were excluded.\u003c/p\u003e \u003cp\u003eThe optimal management strategy for \u0026ge;\u0026thinsp;20mm polyps resected with hot-snare piecemeal endoscopic mucosal resection followed by margin thermal ablation is well defined and recommended by international guidelines.(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) This was not standard practice during the study period and therefore its use was sparse. Hence cases where hot-snare polypectomy with or without margin thermal ablation were excluded from the initial recurrence analysis. For the purposes of all subsequent analyses, i.e. assessment of additional polyps at surveillance as well as outcomes at SC2, all cases of piecemeal polypectomy were included.\u003c/p\u003e \u003cp\u003eEthics\u003c/p\u003e \u003cp\u003eThe study was approved by the Metro North Health Human Research Ethics Committee (EC00172).\u003c/p\u003e \u003cp\u003eProcedure\u003c/p\u003e \u003cp\u003eIndex colonoscopy\u003c/p\u003e \u003cp\u003eThe procedures were performed by a specialist gastroenterologist or advanced trainee under direct supervision. Anaesthetist-directed sedation with a combination of fentanyl, midazolam, and propofol was employed in all cases. High definition colonoscopes (HQ190/EZ1500; Olympus, Tokyo, Japan) and carbon dioxide insufflation were used. Patients received split-dose bowel preparation. This is standard for both centres, and did not change during the period of this study.\u003c/p\u003e \u003cp\u003eThe solution used for submucosal fluid injection was a combination of succinylate gelatin (Gelofusine; B Braun, Bella Vista, Australia) and methylene blue or indigo carmine with or without the use of dilute adrenaline. Dedicated cold snares including Captivator\u0026trade; Cold single-use snare. Alternatives included Captivator\u0026trade; II cold and hot single-use snare (Boston Scientific, Marlborough, Mass, USA) or Snare Master Plus hybrid hot and cold snare (Olympus, Tokyo, Japan). The choice of snare, as well as decision to utilise a distal attachment cap, defect closure with clips, or snare-tip soft coagulation to defect margin, along with tattoo to locate the site at surveillance were at the proceduralist\u0026rsquo;s discretion. For hot polyopectomy, a microprocessor-controlled electrosurgical generator (Endocut effect 3, VIO 300D; ERBE Elektromedizin, T\u0026uuml;bingen, Germany) with fractionated current was used in both centres. Where used, margin thermal ablation was performed using STSC (ERBE VIO 300D, SOFT COAG: 80W, Effect 4; ERBE, Tubingen, Germany).\u003c/p\u003e \u003cp\u003eSurveillance colonoscopy\u003c/p\u003e \u003cp\u003eThe timing of first and second surveillance was determined by the proceduralist based on their confidence of complete resection, quality of prep, known residual polyps, as well as patient factors such as overall health and availability.\u003c/p\u003e \u003cp\u003eThe method of examination of polypectomy site, i.e. use of narrow-band imaging and magnification as well as decision for biopsy of the scar was proceduralist dependent. Lastly, management of recurrence followed by subsequent surveillance recommendation was also proceduralist determined. In the absence of recurrence, outcomes for second surveillance colonoscopy were reviewed.\u003c/p\u003e \u003cp\u003eData collection\u003c/p\u003e \u003cp\u003eIf the patient had both, conventional adenoma as well as a serrated lesions resected piecemeal at index procedure, only the larger lesion was included in analysis. To capture frequency of confident scar identification, all surveillance reports were manually reviewed for either written documentation or photo-documentation of the scar by a single researcher (SS).\u003c/p\u003e \u003cp\u003eThe \u0026lsquo;right colon\u0026rsquo; was defined as including the caecum, ascending colon, hepatic flexure and transverse colon. The \u0026lsquo;left colon\u0026rsquo; includes the descending colon, splenic flexure, sigmoid colon, descending colon and rectum.\u003c/p\u003e \u003cp\u003eThose who were found to have any additional polyps on surveillance colonoscopies were divided in \u0026lsquo;low-risk\u0026rsquo;, \u0026lsquo;high-risk\u0026rsquo;, and \u0026lsquo;very-high risk\u0026rsquo; groups. Those who were only found to have additional polyps that could safely wait for 5 years or longer for surveillance colonoscopy as per the Australian guidelines were considered \u0026lsquo;low risk\u0026rsquo;. \u0026lsquo;High-risk\u0026rsquo; pathology on surveillance colonoscopy was defined as those who would be recommended to undergo a surveillance colonoscopy in 3 years\u0026rsquo; time as per the Australian guidelines. Similarly, as per the national guidelines, those who would be recommended to return for surveillance in 1 year were defined as \u0026lsquo;very high-risk\u0026rdquo;.(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) (Supplementary Table\u0026nbsp;1)\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eAnalyses were conducted using StataNow/MP (Version 19.5; StataCorp LLC, College Station, TX). Univariable methods were used to describe the cohort and assess differences according lesion size (\u0026ge;\u0026thinsp;20mm vs \u0026lt;\u0026thinsp;20mm). Continuous and normally distributed variables were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD, and differences between groups were analysed by one-way ANOVA. Non-normally distributed data are presented as median (range) and were analysed using the Kruskal-Wallis H test. Categorical data were presented as proportional percent and analysed using Pearson\u0026rsquo;s chi-squared (χ 2) or Fisher\u0026rsquo;s Exact test as denoted. Statistical significance was set at alpha\u0026thinsp;=\u0026thinsp;0.05. Granular outcome analysis for high versus very-high risk additional polyps on surveillance could not be performed due to small numbers. Analysis of second surveillance data was no feasible due to rare event rate.\u003c/p\u003e \u003cp\u003eMultivariable logistic regression analysis reported in terms of odds ratios (OR) with associated 95% confidence intervals (CI) was used to examine factors associated with: (i) recurrence among 168 polyps; and (ii) additional high or very high-risk polyps at first surveillance colonoscopy among 202 patients. First, unadjusted ORs are presented. Considering our understanding of the relationships among variables and their clinical relevance, as well as associations assessed first in univariate models and then in a multivariable analysis, we employed forward stepwise selection (p-value for addition\u0026thinsp;\u0026lt;\u0026thinsp;0.20).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eIn the years 2018 and 2019, 7,105 individuals underwent a colonoscopy at the two centres. The mean caecal intubation rate for the whole colonoscopy cohort through the study period was 97.8% with the mean adenoma detection rates of 53.1% and sessile serrated lesion detection rate of 15.5%. In 871 of these procedures surveillance within 3 years was recommended because of high-risk polyps identified at the index colonoscopy. Of these, a significant proportion, i.e. 202 (23%) were surveyed because a piecemeal polypectomy was performed (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eOf the patients with polyps resected piecemeal, 119/202 (59%) had a dominant conventional adenoma and 83 (41%) had serrated lesions predominantly sessile serrated lesions (Supplementary Tables\u0026nbsp;2 and 3). 52% (105/202) of these had polyps that were \u0026lt;\u0026thinsp;20mm in size. Cold-snare polypectomy technique was utilised in 61% (73/119) of those with a conventional adenoma and 94% (78/83) with serrated lesions. Of the minority of polyps resected by hot snare piecemeal polypectomy, 42/53 (79%) were conventional adenomas \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026ge;\u003c/span\u003e\u0026thinsp;20mm. Histological recurrence at SC1 was 6/42 (15%) which likely reflects a low snare tip soft coagulation rate of 43%. Subsequent analysis is focussed on cases resected by cold snare polypectomy.\u003c/p\u003e\n\u003ch3\u003eConventional adenomas resected by cold snare polypectomy\u003c/h3\u003e\n\u003cp\u003eThe patient group were predominantly male with a mean age of 65.1 years (SD\u0026thinsp;=\u0026thinsp;13.4). Of the 82 polyps were resected cold-piecemeal, 57% (47/82) were \u0026lt;\u0026thinsp;20mm in size (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The largest resected lesion measured 50mm and there was a right colon predominance in polyps less than 20mm in size.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics conventional adenomas in 73 patients with 82 polyps resected with cold snare.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003ePatient characteristics (%)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026lt;\u0026thinsp;20mm\u003c/span\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026ge;\u0026thinsp;20mm\u003c/span\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;44 (60)*\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;29 (40)*\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003ep-value\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, mean (SD), years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63.7 (11.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e67.2 (11.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.19\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (31.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13 (44.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePolyp characteristics\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eSize\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emedian (IQR), mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (\u003cspan additionalcitationids=\"CR13 CR14\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (\u003cspan additionalcitationids=\"CR21 CR22 CR23 CR24 CR25 CR26 CR27 CR28 CR29\" citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eLocation\u003c/em\u003e, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRight colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43 (91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28 (80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.19*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExact location\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRectum\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSigmoid, descending colon, splenic flexure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTransverse colon, hepatic flexure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8 (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAscending colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13 (37)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCaecum, IC valve, appendiceal orifice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17 (36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eHistology\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.11*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTubular adenoma with low grade dysplasia (LGD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32 (68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26 (74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTubular adenoma with high grade dysplasia (HGD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTubulovillous adenoma with LGD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTubulovillous adenoma with HGD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePolypectomy technique, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubmucosal injection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30 (64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28 (80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSnare tip soft coagulation (STSC) post polypectomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClip placed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSite tattooed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.079*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOutcome at S1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime from index colonoscopy to first surveillance, median (IQR), months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.0 (6.0\u0026ndash;12.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.0 (4.0\u0026ndash;7.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u0026Dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to S1\u0026thinsp;\u0026lt;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14 (40)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.038\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to \u0026ge;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e38 (81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21 (60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConfident scar identification\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24 (51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25 (71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.063\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSuspected macroscopic recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiopsy/resection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32 (42)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistological recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eSD, Standard deviation; N, frequency; Values are n (%) and Pearson\u0026rsquo;s chi-squared are reported unless otherwise defined; *Fishers exact test; \u0026dagger;Two sample t test; \u0026Dagger;Wilcoxon rank-sum\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe median time to first surveillance was significantly less in the polyps that were \u0026ge;\u0026thinsp;20mm in size with the median time being 6 months (IQR 4.0\u0026ndash;7.0) compared to 8 months (IQR 6.0\u0026ndash;12.0; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) for those measuring less than 20mm. Confident scare identification was 71% in large polyps but only 51% in smaller polyps (p\u0026thinsp;=\u0026thinsp;0.063). Histological recurrence at SC1 was demonstrated in 15% of conventional adenomas \u0026lt;\u0026thinsp;20mm. A lower, rate of histological recurrence at SC1 of 11% was demonstrated in \u0026ge;\u0026thinsp;20mm conventional adenomas resected piecemeal using cold snare but this difference was not statistically significant (p\u0026thinsp;=\u0026thinsp;0.65).\u003c/p\u003e\n\u003ch3\u003eSerrated lesions resected by cold snare polypectomy\u003c/h3\u003e\n\u003cp\u003ePatients with serrated lesions were younger than those with conventional adenomas (mean age 55.9 years (SD\u0026thinsp;=\u0026thinsp;13.7 vs 65.1 years, SD\u0026thinsp;=\u0026thinsp;11.4; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Of the 86 polyps resected with cold-snare polypectomy technique, 25 (29%) were \u0026ge;\u0026thinsp;20mm. Maximum lesion size was 35mm with the smallest lesion resected cold-piecemeal measuring 6mm. Higher risk lesions, i.e. SSL-D and TSAs were infrequent with a total of 3 and 2 polyps respectively.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of serrated lesions in 78 patients with 86 polyps resected using cold snare.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003ePatient characteristics (%)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;20mm\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;20mm\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;55 (71)*\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;23\u003c/b\u003e (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e)\u003cb\u003e*\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003ep-value\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, mean (SD), years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55.7 (14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56.5 (12.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.83\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, female, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40 (72.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16 (69.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.78\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePolyp characteristics\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;61\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eN\u0026thinsp;=\u0026thinsp;25\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eSize\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emedian (IQR), mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (\u003cspan additionalcitationids=\"CR11 CR12 CR13 CR14\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20 (\u003cspan additionalcitationids=\"CR21 CR22 CR23 CR24\" citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eLocation, n (%)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRight colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e51 (84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.32*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExact location\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.025*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRectum\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSigmoid, descending colon, splenic flexure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTransverse colon, hepatic flexure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAscending colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21 (34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17 (68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCaecum, IC valve, appendiceal orifice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eHistology\u003c/em\u003e, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHyperplastic polyp\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8 (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSessile serrated lesion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50 (82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSessile serrated lesion with dysplasia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTraditional serrated lesion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePolypectomy technique\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubmucosal injection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e47 (77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19 (76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.92\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSnare tip soft coagulation post polypectomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClip(s) placed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSite tattooed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOutcome at S1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime from index procedure to first surveillance, median (IQR), months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.0 (6.0\u0026ndash;13.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.0 (5.0\u0026ndash;8.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u0026Dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to S1\u0026thinsp;\u0026lt;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.012\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to S1\u0026thinsp;\u0026ge;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e57 (93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18 (72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConfident scar identification\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17 (57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.012\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSuspected macroscopic recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBiopsy/resection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.066\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistological recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eSD, Standard deviation; N, frequency; Values are n (%) and Pearson\u0026rsquo;s chi-squared are reported unless otherwise defined; *Fishers exact test; \u0026dagger;Two sample t test; \u0026Dagger;Wilcoxon rank-sum\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eTime to first surveillance was significantly greater in patients with serrated polyps that were less than 20mm in size with a median of 9 months (IQR 6.0\u0026ndash;13.0) versus 6 months (IQR 5.0\u0026ndash;8.0; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) in polyps greater than 20mm. Confident scar identification was less common than when conventional adenomas had been resected piecemeal and scar was identified at SC1 in only 30% (18/61) of cases with a serrated polyp \u0026lt;\u0026thinsp;20mm resected piecemeal by cold snare polypectomy vs 57% (17/25 polyp \u0026ge;\u0026thinsp;20mm (p\u0026thinsp;=\u0026thinsp;0.012). Histological recurrence at SC1 was not common after piecemeal polypectomy of serrated lesions (3.4%, 3/86 polyps), with difference according to lesion size (3/61 in polyps \u0026lt;\u0026thinsp;20mm vs none in \u0026ge;\u0026thinsp;20mm; p\u0026thinsp;=\u0026thinsp;1.00). Of these 3 cases, one in the ascending colon may have been related to failure to use submucosal injection to further demarcate the lesion borders and two are likely to be associated with their technically difficult location in the appendiceal orifice which is well known to be a challenging location with high risk of recurrence.\u003c/p\u003e\n\u003ch3\u003eFactors associated with histological recurrence at SC1 after cold-snare polypectomy\u003c/h3\u003e\n\u003cp\u003eThe combined polyp recurrence rate at first surveillance was 8.3% and was more common in conventional adenomas (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Those with polyp recurrence were 11.1 years older (mean 71.0 years [[SD\u0026thinsp;=\u0026thinsp;9.9] vs 59.9 years [SD\u0026thinsp;=\u0026thinsp;13.2]; p\u0026thinsp;=\u0026thinsp;0.003). On univariate analysis, recurrence in the conventional adenoma group was 4.3-fold higher (OR\u0026thinsp;=\u0026thinsp;4.29, 95% CI 1.15\u0026ndash;15.97) as compared to the serrated lesion group (p\u0026thinsp;=\u0026thinsp;0.030) (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Neither polyp location, nor size were statistically significant determinants for recurrence. The only procedural factor significantly associated with recurrence was tattooing. This was associated with an 8.1-fold increased risk of recurrence (95% CI 1.71\u0026ndash;38.55; 0.008). Additionally, less recurrence was found in patients brought back for SC1 later (OR\u0026thinsp;=\u0026thinsp;0.79, 95%CI 0.65\u0026ndash;0.98; p\u0026thinsp;=\u0026thinsp;0.03) although this difference disappeared on multivariable analysis (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Older age was the only factor significantly associated with recurrence (adjusted OR\u0026thinsp;=\u0026thinsp;2.06, 95%CI 1.09\u0026ndash;3.89; p\u0026thinsp;=\u0026thinsp;0.025) on multivariate analysis.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eFactors associated with per-polyp recurrence at first surveillance colonoscopy among 168 polyps resected with cold-snare technique.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge, mean (SD), years\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo recurrence\u003c/p\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;154 (91.7%)*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRecurrence\u003c/p\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;14 (8.3%)*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59.9 (13.3)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e71.0 (9.9)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e85 (55.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (57.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.89\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp histology\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerrated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e83 (53.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (21.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.025*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConventional adenoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e71 (46.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11 (79.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp location (right vs left)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRight colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e133 (86.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14 (100.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.22*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLeft colon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21 (13.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp size (mm), median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e15.0 (12.0\u0026ndash;20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15.0 (12.0\u0026ndash;20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.92\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;20mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e98 (63.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (71.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;20mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e56 (36.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (28.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubmucosal injection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e114 (74.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (71.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.76*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSnare tip soft coagulation post polypectomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3 (1.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.0*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClip(s) placed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e11 (7.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSite tattooed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5 (3.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (21.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.020*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime from index colonoscopy (months) to S1, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.0 (6.0\u0026ndash;12.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.0 (5.0\u0026ndash;6.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eSD, Standard deviation; N, frequency; Values are n (%) unless otherwise defined; *Fishers exact test\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResults from logistic regression analysis assessing factors associated with recurrence among 168 polyps with cold-snare technique.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge in decades\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAdjusted OR (95%CI)*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e2.37 (1.31\u0026ndash;4.29)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e2.06 (1.09\u0026ndash;3.89)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.025\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (female vs male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.08 (0.36\u0026ndash;3.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp histology (conventional adenoma vs serrated)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e4.29 (1.15\u0026ndash;15.97)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.85 (0.67\u0026ndash;12.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePolyp location (right vs left)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(omitted)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSize (\u0026ge;\u0026thinsp;20mm vs \u0026lt;\u0026thinsp;20mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.70 (0.21\u0026ndash;2.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.29 (0.07\u0026ndash;1.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExact size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.03 (0.97\u0026ndash;1.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubmucosal injection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.88 (0.26\u0026ndash;2.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSnare tip soft coagulation post polypectomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(omitted)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClip(s) placed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.17 (0.43\u0026ndash;10.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSite tattooed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e8.13 (1.71\u0026ndash;38.55)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.96 (0.96\u0026ndash;37.13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime from index colonoscopy (months), median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.79 (0.65\u0026ndash;0.98)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.028\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.68 (0.17\u0026ndash;2.82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.60\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: Bold values indicate statistical significance (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05); Not selected (N/S); *Multivariable logistic regression model included histology, age and size (\u0026ge;\u0026thinsp;20mm vs \u0026lt;\u0026thinsp;20mm), procedures clip and tattooing, and time from time from index colonoscopy\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eAdditional polyps at SC1 after cold or hot-snare polypectomy\u003c/h2\u003e \u003cp\u003e75 (34%) of the total study population who underwent both cold and hot-snare polypectomy did not have any additional polyps at SC1. Low risk polyps were found in 87 (39%) and high-risk polyps and very high-risk polyps in 26 (12%) and 33 (15%) respectively. A reason for early surveillance is the detection and removal of high or very high-risk polyps so factors which may predict their occurrence were sought.\u003c/p\u003e \u003cp\u003eThe fifty-four patients (26.6%) who had additional high or very high-risk polyps at first surveillance colonoscopy were 4 years older (67.0 years, IQR 57.0\u0026ndash;73.0) than those who had low risk or no additional polyps(64.8 years, SD\u0026thinsp;=\u0026thinsp;12.6 vs 60.7 years (SD\u0026thinsp;=\u0026thinsp;13.0; p\u0026thinsp;=\u0026thinsp;0.046), and had larger a polyp size (20.0mmm, IQR 15.0\u0026ndash;30.0) vs 18.0mm, IQR 14.0\u0026ndash;25.0), respectively; p\u0026thinsp;=\u0026thinsp;0.022) (Supplementary Table\u0026nbsp;4). In univariate analysis, patients with conventional adenomas appeared to have more high-risk polyps in patients with conventional adenomas, but this did not reach statistical significance (p\u0026thinsp;=\u0026thinsp;0.103). Older age (OR\u0026thinsp;=\u0026thinsp;1.30, 95% CI (I.00-1.68) and larger polyp size (OR\u0026thinsp;=\u0026thinsp;1.03, 95% CI (1.01\u0026ndash;1.05) increased the risk of having additional high or very high-risk polyps at first surveillance colonoscopy. In multivariable analysis including histology, age and polyp exact size, only polyp size was associated with having additional high or very high-risk polyps at first surveillance colonoscopy (adj-OR\u0026thinsp;=\u0026thinsp;1.03, 95% CI 1.00-1.05; p\u0026thinsp;=\u0026thinsp;0.035).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSC2 outcomes post hot and cold-snare polypectomy\u003c/h3\u003e\n\u003cp\u003eAfter exclusion of the 21 patients with recurrence at SC1, follow-up outcomes for the remaining 181 who had undergone either cold or hot-snare polypectomy were reviewed. Of these, 124 (69%) underwent SC2. 76 of them had piecemeal resection of a dominant conventional adenoma at index procedure and 48 had an initial serrated lesion (Supplementary Table\u0026nbsp;5). The numbers are too small to allow for formal statistical comparisons by lesion size. Histological recurrence was confirmed in one case of \u0026lt;\u0026thinsp;20mm serrated polyp where the scar was biopsied, and no recurrence confirmed at SC1. No recurrence was seen in \u0026lt;\u0026thinsp;20mm conventional adenoma subgroup but there were a total 4 cases of recurrence in those with a \u0026ge;\u0026thinsp;20mm conventional adenoma resected piecemeal at index colonoscopy. Scars had been reviewed at SC1 in all four of these cases and biopsies were performed in two cases without histological recurrence at SC1.\u003c/p\u003e \u003cp\u003eNo cancers were identified on SC1 and SC2. Polyp recurrence was endoscopically treated in all cases with the polypectomy technique at the endoscopist\u0026rsquo;s discretion.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study conducted in the context of contemporary, high quality colonoscopy practice demonstrates that surveillance after piecemeal polypectomy contributes significantly to the overall burden of surveillance. The convenience and safety of piecemeal polypectomy especially by cold snare technique needs to be balanced with the need for increased follow-up frequency. Resource conservation and mitigating delays in access to colonoscopy by attempting to lengthen follow-up intervals is a topic of great interest.(\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) Surveillance intervals can only safely be lengthened, however, by either identifying those at lower risk or reducing post-polypectomy recurrence by improving procedural quality, i.e. reducing the incidence of recurrence at polypectomy site as well as identifying residual high-risk polyps at the time of index colonoscopy.\u003c/p\u003e \u003cp\u003eThe frequency of incomplete resection and recurrence varies in the literature.(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan additionalcitationids=\"CR15 CR16\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e) Additionally, studies that provide comparison of outcomes from polypectomies less and greater than 20mm in size are sparse. One contributor to recurrence is polypectomy technique. The evidence surrounding the application of cold snare resection of polyps \u0026lt;\u0026thinsp;20mm has been steadily increasing.(\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e) This technique has comparable efficacy to hot-snare resection for polyps measuring \u0026lt;\u0026thinsp;10mm.(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) For medium sized polyps measuring 10-19mm, however, the literature is less clear with variable reported rates of recurrence after cold snare piecemeal polypectomy.(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e) It is thought to be least appropriate for the resection of larger adenomas \u0026ge;\u0026thinsp;20mm due to significantly higher rates of recurrence with cold polypectomy.(\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e) Currently, international guidelines recommend consideration of conventional, i.e. diathermy based EMR for \u0026ge;\u0026thinsp;20mm non-pedunculated adenomatous polyps.(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) Furthermore, margin thermal ablation to the defect has been shown to dramatically reduce the incidence of recurrence at surveillance compared to conventional resection technique is now recommended as standard practice after hot snare piecemeal polypectomy.(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) This technique is now a firmly established standard of care. Hence, the subgroup with hot-snare polypectomy with or without STSC were not the focus of our analysis\u003c/p\u003e \u003cp\u003eThe primary outcome of this study was assessment of recurrence rates. In those with cold piecemeal resection, we found no significant difference in recurrence with smaller conventional adenomas compared to large adenomas. This was an unexpected finding, and our results may be explained by proceduralist bias, i.e., larger conventional adenomas that are technically more difficult to resect or those with higher risk of recurrence based on optical assessment may have been more likely to be removed using electrocautery. It is worth noting that in the present study, the recurrence rate of conventional adenomas \u0026lt;\u0026thinsp;20mm resected by cold snare polypectomy remains clinically significant at 15%. justifying SC1 at 6 months regardless of adenoma size unless improvement in techniques can reduce recurrence.\u003c/p\u003e \u003cp\u003eApart from use of submucosal injection, overlapping tissue and wide margin resection, few auxiliary techniques have been shown to improve recurrence rates post cold resection. The technique of cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST) has been employed in cases with non-lifting large non-pedunculated polyps as well as in treating recurrence at surveillance.(\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e) This demonstrates the role of thermal ablation as a safe and effective adjunct to reduce recurrence outside of conventional EMR. This raises the question of thermal ablation post-cold-polypectomy but this has not been formally evaluated or validated.\u003c/p\u003e \u003cp\u003eThe only procedural technique with a trend towards higher risk of recurrence was tattoo placement. This could be explained by the possibility that proceduralists were more likely to place a tattoo when additional macroscopic predictors of recurrence risk are macroscopically evident or alternatively when their confidence in complete resection was lower.(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) This trend was also noted where risk of recurrence is lower in those who underwent later first surveillance. Given the small numbers, chance cannot be ruled out, however, this may indicate the value of proceduralist confidence in complete resection and risk identification.\u003c/p\u003e \u003cp\u003eMirroring the trend in the literature for serrated lesions, recurrence rates were very significantly lower in this subgroup as compared to conventional adenomas.(\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e) Owing to high rates of complete resection, routine use of this method for polyps \u0026lt;\u0026thinsp;20mm is accepted. Additionally, our results support the extension of this technique to large sessile polyps \u0026ge;\u0026thinsp;20mm.(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan additionalcitationids=\"CR27\" citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e) Typically, size is thought to be an important factor where larger lesions are more likely to be associated with recurrence. Like conventional adenomas, we found paradoxically the only 3 cases of recurrence in polyps measuring \u0026lt;\u0026thinsp;20mm and all 3 of the lesions had specific factors, i.e. lack of utilisation of submucosal injection as well as location at the appendiceal orifice, which may have contributed to incomplete resection.(\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eAn important consideration when assessing recurrence is accurately identifying the location of previous polypectomy. Although the reliability of careful optical assessment of post-polypectomy scar has been demonstrated and routine biopsies are not necessary, small polypectomy scars can be difficult to confidently locate.(\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e) Literature comparing frequency of scar identification post cold polypectomy for smaller polyps is sparse. Like Mass \u003cem\u003eet al\u003c/em\u003e., we found that scar identification and documentation is infrequent in everyday practice.(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) Scar identification could be aided by uncommonly employed techniques such as tattoo, clips, cautery or hot snare for smaller lesions however all these techniques come at a cost and add more time to the procedure\u003c/p\u003e \u003cp\u003eOur secondary outcome was to assess additional lesions at surveillance. We found a clinically significant rate of \u0026lsquo;very high-risk lesions\u0026rsquo; on surveillance in an endoscopy unit with high performance on validated quality indicators. The prevalence of very high-risk polyps at SC1 was 15%. Overall, those at highest risk were more likely to be older and have a larger polyp resected. Age and polyp size have been previously shown to be a potential predictors of the risk of additional polyps although it is disappointing that the prevalence of very high risk polyps should be so high 6 months after a high quality colonoscopy.(\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eWhile the strength of this study is the real-world nature of the outcomes, the heterogeneity in practice from multiple operators and retrospective nature of the study is a limitation. Given that decisions were dictated by the individual endoscopist, including interval for returning for surveillance, the potential for bias exists. Furthermore, the cohort size limits evaluation of subgroups that might benefit from lengthening surveillance interval, and our findings should be interpreted with caution as there may have been differences that the study did not detect.\u003c/p\u003e \u003cp\u003eAlthough serrated lesions have a low risk of recurrence, the finding of high-risk additional polyps is not negligible and should be an important consideration. The recurrence rates for conventional adenomas were reasonably high and not dependent on size. For hot snare piecemeal polypectomy, this is likely to change as margin thermal ablation post polypectomy becomes the universal standard of care. Whether there is a role for ablation post-cold-snare polypectomy as a simple auxiliary technique to eradicate the possibility of microscopic polyp remnants despite overlapping snare and side resection remains an unexplored concept.\u003c/p\u003e \u003cp\u003eThis real-world study shows that cold piecemeal polypectomy even for smaller lesions is a significant contributor to the burden of surveillance. Most of the cases are performed by cold snare technique which enhances safety but limits adoption of adjuvant techniques to lower recurrence and chances of identifying previous polypectomy location. Additionally, this is associated with a clinically significant risk of recurrence in conventional adenomas even \u0026lt;\u0026thinsp;20mm. Especially while the optimal approach for medium-sized (10-19mm) polyps is still debated, our findings support the current conservative approach with the recommendation of first surveillance at 6 months to ensure early detection and management. If delayed surveillance were to be considered, younger patients with index serrated lesions would be the most suitable candidates to be considered however further prospective studies are required.\u003c/p\u003e"},{"header":"Conclusions","content":" \u003cp\u003eRecurrence risk after piecemeal resection differs by polyp subtype and resection technique. Serrated lesions demonstrated low recurrence, suggesting surveillance intervals may be safely extended in selected patients with adequate index clearance. In contrast, conventional adenomas\u0026mdash;even \u0026lt;\u0026thinsp;20 mm\u0026mdash;showed higher recurrence following cold resection, supporting the need for optimised resection techniques and continued early surveillance in this group.\u003c/p\u003e "},{"header":"Declarations","content":"\u003ch2\u003eConflict of interest:\u003c/h2\u003e \u003cp\u003eThe authors declare no conflicts.\u003c/p\u003e \u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eSS and BL conceptualised the study. Initial data was synthesised by KH and subsequently analysed by PV. SS, PV and BL interpreted the data. SS drafted the initial article with critical revisions by SS, MA, PV and BL. All authors approved the final version of the manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe Royal Brisbane and Women\u0026rsquo;s Hospital (RBWH) and Surgical Treatment and Rehabilitation Service (STARS) maintain a prospective data base (Colonoscopy Outcomes Registry) of every patient who has undergone colonoscopy from February 2018 onwards. Post procedure and subsequent availability of histology results, surveillance nurses dedicated to this task manually enter patient demographics and procedure details, including bowel preparation quality, completion of procedure as well as polyp numbers, size, and location. Lastly, the histology findings, procedure details and subsequent surveillance recommendations are all entered in a standardized format on a secure web application (REDCap).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMangira D, Raftopoulos S, Vogrin S, Hartley I, Mack A, Gazelakis K, et al. Effectiveness and safety of cold snare polypectomy and cold endoscopic mucosal resection for nonpedunculated colorectal polyps of 10\u0026ndash;19 mm: a multicenter observational cohort study. Endoscopy. 2023.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTutticci NJ, Hewett DG. Cold EMR of large sessile serrated polyps at colonoscopy (with video). Gastrointest Endosc. 2018;87(3):837\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVan Hattem WA, Shahidi N, Vosko S, Hartley I, Britto K, Sidhu M, et al. 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Gut. 2025;74(1):67\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFerlitsch M, Hassan C, Bisschops R, Bhandari P, Dinis-Ribeiro M, Risio M, et al. Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline\u0026ndash;update 2024. Endoscopy. 2024;56(07):516\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarclay K, Leggett, B, Macrae, F, Bourke, M, Ee H, Cancer Council Australia Surveillance Colonoscopy Guidelines Working Party Cancer Council Australia Surveillance Colonoscopy Guidelines Working Party. Clinical question:What should be the surveillance colonoscopy for patients with adenoma multiplicity with or without polyposis syndrome? Sydney [cited 2023 June 09]. 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Endoscopy. 2014;46(05):388\u0026ndash;402.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoss A, Williams SJ, Hourigan LF, Brown G, Tam W, Singh R, et al. Long-term adenoma recurrence following wide-field endoscopic mucosal resection (WF-EMR) for advanced colonic mucosal neoplasia is infrequent: results and risk factors in 1000 cases from the Australian Colonic EMR (ACE) study. Gut. 2015;64(1):57\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKlein A, Tate DJ, Jayasekeran V, Hourigan L, Singh R, Brown G, et al. Thermal ablation of mucosal defect margins reduces adenoma recurrence after colonic endoscopic mucosal resection. Gastroenterology. 2019;156(3):604\u0026ndash;13. e3.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePohl H, Rex DK, Barber J, Moyer MT, Elmunzer BJ, Rastogi A, et al. Cold snare endoscopic resection for large colon polyps: a randomised trial. Gut. 2025;74(11):1804\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuardiola JJ, Anderson JC, Kaltenbach T, Pohl H, Rex DK. Cold snare resection in the colorectum: when to choose it, when to avoid it, and how to do it. Clinical Gastroenterology and Hepatology. 2025;23(4):507\u0026ndash;15. e6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKaltenbach T, Anderson JC, Burke CA, Dominitz JA, Gupta S, Lieberman D, et al. Endoscopic removal of colorectal lesions: recommendations by the US Multi-Society Task Force on Colorectal Cancer. Official journal of the American College of Gastroenterology| ACG. 2020;115(3):435\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003evon Renteln D, Djinbachian R, Benard F, Barkun AN, Bouin M, Bouchard S, et al. Incomplete resection of colorectal polyps of 4\u0026ndash;20 mm in size when using a cold snare, and its associated factors. Endoscopy. 2023;55(10):929\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eO\u0026rsquo;Sullivan T, Cronin O, van Hattem WA, Mandarino FV, Gauci JL, Kerrison C, et al. Cold versus hot snare endoscopic mucosal resection for large (\u0026ge;\u0026thinsp;15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial. Gut. 2024;73(11):1823\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilliams TJ, Mickenbecker M, Smith N, Bhasker V, Rubtsov D, Jones A, et al. Efficacy of cold piecemeal EMR of medium to large adenomas compared with sessile serrated lesions. Gastrointestinal Endoscopy. 2025;101(1):178\u0026ndash;83.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMandarino FV, O'Sullivan T, Gauci JL, Kerrison C, Whitfield A, Lam B, et al. Impact of margin thermal ablation after cold-forceps avulsion with snare-tip soft coagulation for nonlifting large nonpedunculated colorectal polyps. 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Endoscopy International Open. 2021;9(06):E867-E73.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"digestive-diseases-and-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ddsj","sideBox":"Learn more about [Digestive Diseases and Sciences](http://link.springer.com/journal/10620)","snPcode":"10620","submissionUrl":"https://submission.nature.com/new-submission/10620/3","title":"Digestive Diseases and Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"piecemeal, surveillance, recurrence, cold snare polypectomy","lastPublishedDoi":"10.21203/rs.3.rs-9350411/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9350411/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground and Aims: \u003c/strong\u003eCurrent guidelines recommend early surveillance following piecemeal polypectomy due to recurrence risk; however, this contributes substantially to colonoscopy burden. We aimed to identify subgroups in which \u003cstrong\u003esurveillance can be safely deferred beyond current guideline intervals in selected patients.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e We performed a two-centre retrospective study of consecutive patients undergoing first (SC1) and second (SC2) surveillance colonoscopy following piecemeal resection. Primary outcome was histological recurrence; secondary outcome was detection of additional high-risk polyps.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003e\u0026nbsp;A total of 221 lesions, 130 conventional adenomas (CA) and 91 serrated lesions (SL) were resected piecemeal in 202 patients, with 76% removed using cold snare technique.\u003c/p\u003e\n\u003cp\u003eRecurrence following cold resection occurred in 11% of CA ≥20 mm and 15% of CA \u0026lt;20 mm, while recurrence in SL was low (5% for \u0026lt;20 mm; 0% for ≥20 mm). Hot snare resection was predominantly used for larger CA (79% ≥20 mm) and was associated with a recurrence rate of 14%. Increasing age was associated with higher recurrence risk.\u003c/p\u003e\n\u003cp\u003eAt SC1, additional high-risk polyps were detected in 27% of patients, particularly following resection of larger index lesions. No advanced neoplasia was detected at SC2 in patients with serrated lesions without recurrence at SC1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eRecurrence risk after piecemeal resection differs by polyp subtype and resection technique. Serrated lesions demonstrated low recurrence, suggesting surveillance intervals may be safely extended in selected patients with adequate index clearance. In contrast, conventional adenomas—even \u0026lt;20 mm—showed higher recurrence following cold resection, supporting the need for optimised resection techniques and continued early surveillance in this group.\u003c/p\u003e","manuscriptTitle":"Surveillance outcomes in an Australian cohort undergoing piecemeal polypectomy for conventional adenomas and serrated lesions","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-19 12:33:04","doi":"10.21203/rs.3.rs-9350411/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-28T02:35:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-26T11:06:11+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-26T08:35:58+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-22T20:16:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"303760615598886643127679076091139085787","date":"2026-04-13T03:21:22+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"175896500236277680567413173982336189680","date":"2026-04-12T05:13:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"76163412830554068792135000405998960303","date":"2026-04-11T14:16:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"213600295512247997206823472242208052418","date":"2026-04-10T11:06:12+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-10T04:12:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-10T01:13:11+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-08T15:35:34+00:00","index":"","fulltext":""},{"type":"submitted","content":"Digestive Diseases and Sciences","date":"2026-04-08T01:59:05+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"digestive-diseases-and-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ddsj","sideBox":"Learn more about [Digestive Diseases and Sciences](http://link.springer.com/journal/10620)","snPcode":"10620","submissionUrl":"https://submission.nature.com/new-submission/10620/3","title":"Digestive Diseases and Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5b345b06-4515-4183-9527-3b2a1e98b24c","owner":[],"postedDate":"April 19th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-19T12:23:23+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-19 12:33:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9350411","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9350411","identity":"rs-9350411","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}