Endoscopic Surveillance in Serrated Polyposis Syndrome: Two or Three-Year Intervals. A Noninferiority Randomized Trial

Endoscopic Surveillance in Serrated Polyposis Syndrome: Two or Three-Year Intervals. 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A Noninferiority Randomized Trial Jorge López-Vicente, Daniel Rodríguez-Alcalde, Luis Hernández Villalba, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8642140/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 21 Apr, 2026 Read the published version in Digestive Diseases and Sciences → Version 1 posted 11 You are reading this latest preprint version Abstract Background: Serrated polyposis syndrome, the most prevalent colonic polyposis, confers an increased colorectal cancer risk. Guidelines recommend close colonoscopy surveillance, but recent data suggest low neoplasia rates, supporting longer colonoscopy intervals. Aims: Compare advanced neoplasia incidence between two- and three-year surveillance. Methods: A multicentre, randomized noninferiority trial was performed (May 2021–November 2024) in six Spanish hospitals. Patients meeting 2019 serrated polyposis syndrome WHO criteria I or II, with no advanced polyps and <5 relevant polyps at their previous colonoscopy, were randomized to surveillance at two or three years. The primary endpoint was advanced neoplasia incidence. Results: A total of 131 patients with serrated polyposis syndrome were included (47.3% women; mean age 66.1). Seventy-two were assigned to 2-year and 59 to 3-year colonoscopy. Among 771 resected lesions, 2.4% were advanced adenomas or advanced serrated polyps; no colorectal cancer was detected. The proportion of patients with advanced neoplasia in the surveillance colonoscopy was 6.9% (2-year) vs 13.6% (3-year), with no statistical difference (p=0.208) but with a risk difference of +6.7% (95% CI: –4.1% to 17.5%) exceeding the pre-specified non-inferiority margin of +10%. Time since serrated polyposis syndrome diagnosis <3 years was associated with advanced neoplasia (OR: 4.4; 95% CI: 1.52-14.75; p=0.024). Conclusions: In patients with serrated polyposis syndrome, extending colonoscopy surveillance intervals to three years was not shown to be non-inferior to a two-year interval for advanced neoplasia incidence. The early years of follow-up after serrated polyposis syndrome diagnosis was identified as a risk factor for advanced neoplasia. Clinical trial registry : ClinicalTrials.gov (NCT04906343). Date: 5-10-2021. polyp vigilance cancer surveillance Figures Figure 1 Figure 2 Figure 3 BACKGROUND Serrated polyposis syndrome (SPS) is the most prevalent colorectal polyposis syndrome, ranging from 0.31% to 0.80% in faecal occult blood test or faecal immunochemical test-based screening programs and from 0.1% to 0.4% in colonoscopy-based programs[1][2] [3] [4]. SPS is characterized by the presence of multiple colonic serrated polyps (SP), including hyperplastic polyps (HP), sessile serrated lesions (SSL) and traditional serrated adenomas (TSA). Diagnosis is based on clinical criteria established by the World Health Organization (WHO). The fifth edition of the WHO Classification of Tumours of the Digestive System , published in July 2019, defines SPS by either of the following criteria: Criterion I, ≥5 SP proximal to the rectum, all ≥5 mm in size, with at least 2 being ≥10 mm; or Criterion II, >20 SP of any size distributed throughout the large bowel, with at least 5 located proximal to the rectum[5] [6]. SPS is associated with an increased risk of colorectal cancer (CRC) compared to the general population. Two large cohort studies have estimated a wide range of CRC incidence, from 15% to 29%[7] [8]. A 2022 meta-analysis reported an overall CRC risk of 19% (95% CI, 15.3%–24.5%), with higher rates at the time of or prior to SPS diagnosis (14.7% [95% CI, 11.4%–18.8%] and 7% [95% CI, 4.5%–10.7%], respectively)[9]. However, the CRC incidence during surveillance appears lower than initially described, with a reported rate of 2.8% (95% CI, 1.8%–4.4%)[9] [10]. Once SPS is diagnosed, all polyps ≥5 mm or with dysplastic appearance (adenoma, SSL or TSA) must be resected. Ideally, this should be achieved via polypectomy, although surgical resection may be required if the polyp burden cannot be managed endoscopically. After this clearing phase, close endoscopic surveillance is required. Long-term studies report a 5-year cumulative incidence of advanced neoplasia (AN)—CRC, advanced adenomas (AA), or advanced SP—of 21.6%–44% during surveillance and after de clearance phase [11] [12] [13][14]. In a prospective cohort of 142 patients with a 10-year follow-up and regular colonoscopy (1–2 years), only one CRC case was detected. In this study, the incidence of AN at different surveillance rounds remained below 16%[14]. Risk factors identified for CRC or AN include smoking, proximal SSL, SP with dysplasia, AA, advanced SP, and SPS 2010 WHO criterion I[13]. These data had led to the proposal of personalized surveillance based on individual risk. Due to limited evidence, surveillance recommendations differ across countries and scientific societies. The U.S. Multi-Society Task Force in 2012 advised annual colonoscopy [15], the American College of Gastroenterology in 2015 suggested 1–3 years[16], the Spanish Society of Gastroenterology in 2018 proposed 1–3 years[17] and the British Society of Gastroenterology in 2020 recommended 1–2 years surveillance[18], based on histology and the size of lesions detected during last colonoscopy. The 2019 European Society of Gastrointestinal Endoscopy (ESGE) guideline on endoscopic management of polyposis syndromes, recommends surveillance intervals based on the findings of the most recent colonoscopy: 1 year after resection of ≥1 advanced polyp or ≥5 relevant non-advanced polyps (adenomas, SSL, TSA or HP ≥5 mm), and 2 years otherwise (strong recommendation and low quality of evidence)[19]. A prospective multicentre study of 271 patients with SPS (median follow-up 3.6 years) supported these recommendations, showing AN incidence of 15.6% with biennial vs 24.4% with annual surveillance (OR 0.57, 95% CI, 0.31–1.07; p=0.08). Only two CRC cases occurred, yielding 5-year incidence of 1.3%, while the 5-year cumulative AN incidence was 44% (95% CI, 37%–52%). SPS WHO criterion I conferred higher AN risk than criterion III (2010 WHO criteria), whereas other factors were not significant. Notably, patients who had undergone prior surveillance colonoscopy before enrolment had lower risk of AN (HR 0.64, 95% CI, 0.41–0.99; p=0.047)[20]. Since biennial surveillance is not associated with increased AN, extending intervals beyond 2 years may be safe, effective and could alleviate the burden on endoscopy units. We therefore designed a non-inferiority randomized controlled trial to evaluate extended surveillance intervals in patients with SPS, specifically in individuals without advanced polyps or with fewer than five relevant polyps in their last colonoscopy. Patients were randomized to undergo colonoscopy at either two years or three years, and the primary outcome was the incidence of AN in each group. METHODS Study Design This multicentre randomized controlled trial (1:1) was conducted from May 2021 to November 2024 in six Spanish hospitals, five with high-risk digestive cancer clinics. Patients fulfilling 2019 SPS WHO criteria and under surveillance were randomized to colonoscopy at 2 years (group A) or 3 years (group B). Randomization was performed and data were collected for all centres via the online database REDCap (Research Electronic Data Capture), an electronic data capture tool hosted by the Spanish Society of Digestive Endoscopy (SEED; www.wseed.es)[21]. The study complied with the Declaration of Helsinki, was approved by ethics committees ( Comité ético de investigación del Hospital Universitario de Móstoles. ID: 2021/005 ) and registered at ClinicalTrials.gov (NCT04906343). Written informed consent was obtained from all individual participants included in the study. All authors had access to the study data and approved the final manuscript. This research was supported by a grant from the Spanish Society of Digestive Endoscopy Foundation (FSEED) in November 2021. Inclusion and Exclusion Criteria Eligible patients were aged ≥18 years with 2019 SPS WHO criteria I, II or both, having completed the clearing phase, and with <5 relevant polyps and no advanced polyps at last colonoscopy. Thus, all patients had a recommended two-year surveillance interval according to ESGE guidelines before randomization[19]. Adequate bowel preparation (Boston Bowel Preparation Scale (BBPS) ≥2 in all segments[22] and cecal intubation in prior colonoscopy were required. Exclusion criteria were patients with inflammatory bowel disease, other hereditary CRC syndromes (e.g., familial adenomatous polyposis, Lynch syndrome, Peutz-Jeghers syndrome, Cowden syndrome, juvenile polyposis syndrome), total colectomy, a piecemeal-resected lesion or invasive cancer at previous colonoscopy, and colonoscopy outside the scheduled window (±3 months). Definitions: Advanced polyps: AA or advanced SP. Relevant polyps: SSL or adenomas (any size), TSA or HP ≥5 mm. Clearing phase: resection of polyps ≥5 mm or with dysplasia (adenomas, TSA, SSL)[19]. Clinical and Demographic Characteristics Collected variables were age, sex, smoking history, SPS criteria, personal CRC history, prior surgery, history of AA or advanced SP, and number of surveillance colonoscopies after clearing phase. Colonoscopy Procedures High-definition (HD) endoscopes were used in all procedures, with chromoendoscopy, virtual chromoendoscopy or white light at endoscopist discretion. Bowel preparation protocols followed each centre’s standard practice and an adequate bowel preparation was defined as BBPS ≥2 in all segments[22]. Sedation was administered at the discretion of the endoscopist or anaesthesiologist. Polyps were classified according to the Paris morphology classification[23]. Location, size, and resection technique were recorded. Complications, including bleeding, perforation, or cardiorespiratory events occurring during the procedure or within the first month afterward, were documented. Only events requiring endoscopic intervention, hospitalization, or surgery were recorded. Histopathology Tissue specimens were processed by gastrointestinal pathologists using the Vienna classification for gastrointestinal epithelial neoplasia[24]. Invasive cancer was defined as neoplastic extension into the submucosa or beyond. Polyp classification was based on WHO criteria[25]: SP: HP, SSL (with or without dysplasia) and TSA. AA: Adenomas ≥10 mm, villous component and/or with high-grade dysplasia. Advanced SP: SP >10 mm and/or with dysplasia. AN: Includes AA, Advanced SP and CRC. Study Outcomes Primary: compare AN incidence between 2- and 3-year groups with a non-inferiority analysis. Secondary: compare relevant polyps incidence, identify risk factors for AN and changes in surveillance recommendations based on ESGE guidelines. Sample Size Calculation Based on a Dutch study by Bleijenberg et al., reporting a 15.6% AN incidence at two-year colonoscopy in low risk-patients [20], the noninferiority margin between the 2 years interval and the 3 years strategy was set to +10%. A total of 136 patients (68 per group) were required to achieve 80% power (β=0.2) to demonstrate non-inferiority, with a one-sided 0.025 contrast (type I error) and a 5% significance level, accounting for 10% expected losses. Statistical Analysis Statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS), version 25.0 for Windows (IBM Corp., 2012. NY: IBM Corp., USA). Quantitative variables were expressed in mean and standard deviation (±SD) and qualitative variables were expressed in frequency (%). In the noninferiority analysis a 1-sided confidence interval approach was used, with a preestated margin of non-inferiority (Δ) of +10%. Two-stage analyses were performed using Fisher's test, χ2 test, and multiple logistic regression analysis to identify the variables that predicted AN. Factors reaching p<0.20 in univariate analysis were analysed using a multivariate logistic regression test. Univariate analysis and multivariate logistic regression results were summarized as the odds ratio (OR) with 95% confidence interval (CI) for the OR. A p-value <0.05 was considered statistically significant. RESULTS Patient Characteristics A total of 145 patients were enrolled in the study, 74 randomized to 2-year follow-up colonoscopy (Group A) and 71 to 3-year follow-up (Group B). The study flow-chart following the Consolidated Standards of Reporting Trials (CONSORT) guidelines is presented in Figure 1. Fourteen patients were excluded after randomization: 4 due to inadequate bowel preparation and 10 because they were lost in follow-up or underwent colonoscopy outside surveillance window (4% in the 2-year and 16.9% in the 3-year group). This left 131 patients for the data analysis, 72 in Group A and 59 in Group B. Mean age was 66.1 years (range 33.4–79.6), and 47.3% were women. At inclusion, 20 patients (15.3%) met WHO criterion I, 88 (67.2%) criterion II, and 23 (17.5%) both. Ten patients (7.6%) had a prior history of CRC. SPS diagnosis was established a mean of 4.9 years before inclusion (range 1–11). Patients had a median of 6.5 colonoscopies (range 2–22) before enrolment, and 2.9 surveillance procedures after the clearing phase (range 0–7). Only 7 patients (5.3%) were randomized immediately after the clearing phase, while 105 (80.2%) had ≥2 surveillance colonoscopies before randomization. Baseline characteristics of patients by group are detailed in table 1. Procedures and Adverse Events All procedures used HD technology. Virtual chromoendoscopy was applied in 30 cases (23.8%), chromoendoscopy with indigo carmine in 69 (53.1%), and white light alone in 30 (23.1%). No adverse events as bleeding, perforation or cardiopulmonary complications were reported. Procedure duration and withdrawal time were similar between groups (table 2). Lesions and Outcomes Across 124 patients, 771 polyps were resected, and 7 patients had no lesion. Twelve polyps lacked histology, and 140 (18.3%) were normal tissue, leaving 619 lesions for analysis. The morphological and histological characteristics of polyps are shown in table 2. Among these, 15 (2.4%) polyps were AN—6 in group A (1.7%) and 9 in group B (3.4%), p=0.177. Fourteen were advanced SP and one was an AA; no CRC was detected. Relevant polyps (SSL, adenomas, TSA or HP ≥5 mm) accounted for 289 (46.7%): 170 (48.2%) in group A and 119 (44.7%) in group B, p=0.398. Mean polyp size was similar between the two groups: 3.74 mm (95% CI: 3.52–3.94) vs 3.77 mm (95% CI: 3.57–3.96), p=0.819; as the mean number of polyps per colonoscopy 5.9 (95% CI: 5.1–6.8) vs 5.3 (95% CI: 4.4–6.3), p=0.336, group A and group B respectively. The overall incidence of patients with at least one AN was 9.9% (95% CI, 4.8–15.1%), with 5/72 patients (6.9%) in group A and 8/59 (13.6%) in group B, p=0.208. The risk difference was +6.7% (95% CI, –4.1 to 17.5; p=0.27). Since the upper bound of the confidence interval exceeds the pre-specified noninferiority margin of +10%, non-inferiority of the 3-year strategy could not be established. Therefore, results regarding noninferiority analysis are inconclusive. Figure 2. Patients with ≥5 relevant polyps were 18.1% in group A vs 15.3% in group B, with no statistical difference (OR 0.81, 95% CI, 0.32–2.07; p=0.670). According to ESGE polyposis guideline recommendations, 30/131 patients (22.9%) should return to a 1-year surveillance interval, due to the detection of at least one advanced polyp or ≥5 relevant polyps, with no difference between groups (22.2% in group A vs 23.7% in group B, p=0.838); Figure 3. A post hoc power analysis yielded a statistical power of 33.8%. Association between advanced neoplasia and patient characteristics Table 3 shows associations between patient variables and AN. In univariate analysis, shorter time since SPS diagnosis and fewer number of colonoscopies after the clearing phase significantly predicted AN. Patients diagnosed from SPS <3 years had a 7.1-fold higher risk (95% CI, 2.05–24.33; p<0.001), and those with <2 colonoscopies after clearing phase had a 3.1-fold higher risk (95% CI, 1.05–9.58; p=0.036). A history of advanced SP also suggested increased risk of AN (OR 4.1, 95%CI, 0.87–19.73; p=0.056), but not reaching statistical significance. In multivariate analysis (table 4), only time since SPS diagnosis remained an independent predictor of AN: patients diagnosed from SPS <3 years had 4.4-fold greater risk (95% CI, 1.52–14.75; p=0.024). Association between relevant polyps and patient characteristics The statistical analyses of predictors for relevant polyps are presented in table 3. In univariate analysis, time since SPS diagnosis was a significant predictor of relevant polyps: patients diagnosed <3 years had 2.12-fold higher risk (95% CI, 1.01–4.41; p=0.048). In multivariate analysis (table 4), time since SPS diagnosis remained a significant predictor for relevant polyps: patients diagnosed <3 years had 2.05-fold greater risk (95% CI, 1.19–3.94; p=0.033). DISCUSSION In this randomized multicentre trial, non-inferiority of the 3-year follow-up strategy could not be established. The incidences of AN in the surveillance colonoscopy (6.9% in 2-year group vs 13.6% in 3-year group) were lower than expected based on previous literature. It is important to highlight that, in our study, patients did not present advanced lesions on the previous colonoscopy; therefore, they could be considered a low-risk group for AN. Bleijenberg et al., in a single-centre cohort of patients with SPS with a prospective 10-year follow-up and surveillance intervals of either 1 or 2 years, reported a relatively stable incidence of AN ranging from 8.7% to 24.2%[14]. Another single-centre cohort from Spain reported a 3-year cumulative AN incidence at 12.1% in 109 monitored patients, which aligns with our cohort [13]. The largest prospective study, involving 271 patients with SPS with a median follow-up of 3.6 years, described a cumulative AN incidence of 44% at five years[20]. This study suggested that AN incidence declines after surveillance, with lower risk in patients who had at least one prior colonoscopy (HR 0.64, 95% CI: 0.41 to 0.99, p=0.047). In that cohort, 31% of patients had prior follow-up, whereas 69% underwent their first surveillance colonoscopy after inclusion. In our study, only 7 patients (5.3%) had their first surveillance colonoscopy after inclusion—considerably lower than in the Bleijenberg study. Even more, 105 of 131 patients (80.2%) had undergone at least two surveillance colonoscopies after the clearing phase. In univariate analysis, patients with fewer than two colonoscopies after the clearing phase had over threefold higher AN risk, even though this association was not confirmed in multivariable analysis. Moreover, in our study, time since SPS diagnosis was also associated with AN detection at surveillance colonoscopy. Our findings suggest that patients with longer follow-up, longer interval since SPS diagnosis and more colonoscopies after the clearing phase have a lower risk of developing AN. Given that most participants were already under prolonged surveillance before enrolment and had no advanced lesions in their last colonoscopy, these two factors may explain the slightly lower incidence of AN observed in our cohort. Several risk factors have been linked to CRC and AN incidence in retrospective studies, including the presence of SP with dysplasia, previous AA or advanced SP, and fulfilling both SPS WHO criteria I and III (2019 criteria II)[7] [8] [12]. Although these retrospective studies included a large number of patients, their findings were not corroborated in a subsequent prospective study[14]. Our results did not establish a relationship between these risk factors and AN occurrence. Gender, smoking status, age, prior AN, and SPS WHO criteria were not associated with AN detection. However, patients with prior advanced SP had a higher proportion of AN compared to those without (13.5% vs 3.6%), a difference approaching statistical significance [OR: 4.14 (95%IC: 0.87-19.73), p=0.056]. While our sample size was relatively large, it may not have been sufficiently powered to detect associations between risk factors and AN. Meeting 2019 SPS criteria I or I+II in our study was linked to nearly double the AN risk (14% vs 8%), but without statistical significance [OR: 1.88, (95% CI: 0.59–5.97), p=0.28]. These data are comparable with larger retrospective and prospective cohorts that found significant higher AN incidence in patients meeting criteria I or I+III (2019 criteria II)[13] [20]. However, those studies were mainly retrospective and focused on 5-year cumulative AN incidence, while ours assessed 2- and 3-year intervals. Our cohort also included more patients meeting only SPS criterion II (67.2%) compared to other studies (36.5–45.3%)[7] [20]. Perhaps with a larger cohort including more SPS criterion I patients, differences might reach significance, potentially confirming a higher AN risk in these individuals. Notably, the only meta-analysis on CRC risk in SPS found no differences across WHO criteria[9]. In our cohort, 10 of 131 patients (7.6%) had a history of CRC, lower than reported in the literature. A meta-analysis by Müller et al. estimated a 14.7% CRC risk prior to SPS diagnosis and 2.8% during surveillance[9]. No cases of CRC were detected at either the 2- or 3-year follow-up in our study, consistent with previous findings from two retrospective series: one including 60 patients (mean follow-up, 2.1 years) and another with 96 patients (median, 3.6 years), as well as a single-centre prospective study of 41 patients followed for 3.1 years, all of which reported no incident CRC cases[11] [26] [27] . In a Dutch prospective cohort (>10 years), only one CRC occurred, yielding a 5-year incidence of 1.0% (95% CI, 0–2.9%)[14]. These findings support the low risk of CRC during surveillance in patients with SPS, particularly with the use of HD-endoscopy and specialized endoscopist care. In recent years, greater awareness of SPS has enhanced early detection in screening programs and routine colonoscopies, allowing diagnosis as soon as WHO criteria are met and potentially preventing the development of advanced polyps. All participating centres in our study were secondary hospitals that do not receive patients from other institutions. This differs from specialized referral centres, where selection bias may lead to a higher proportion of aggressive SPS phenotypes and, consequently, increased AN incidence. A total of 771 polyps were resected across 131 colonoscopies, with a mean of 5.9 polyps per procedure. In comparison, another long-term follow-up study[14] reported 1308 polypectomies across 447 colonoscopies, with a mean of 2.9 polyps per procedure. Most resected polyps in our study were small, distributed throughout the colon and with highest frequence in the transverse colon (28%). On the other hand, 18.3% of resected polyps were histologically normal tissue, data often not reported. This suggests that the high number of small polyps may have led to the resection of lesions that lacked histological abnormalities. Given that 67.2% of our patients met only SPS WHO criterion II and they typically present with numerous small polyps, this could have contributed to the high rate of small, non-advanced polyps and normal-tissue resections. Importantly, no carcinoma or high-grade dysplasia was detected in any colonoscopy. The absence of adverse events was likely due to the study’s sample size, which may not have been sufficient to capture such occurrences, and also to the high number of diminutive lesions resected. The estimated incidence of post-polypectomy bleeding in different series is approximately 0.6-1.8%[28], while perforation rates following colonic endoscopic mucosal resection range from 0.08% to 0.11%[29][30]. However, this does not negate the risks and inconveniences associated with colonoscopy surveillance, including the potential impact on patients' daily activities [30]. Withdrawal time was consistently high across procedures, with a mean ≥ 20 minutes in both groups. Chromoendoscopy—either virtual or with indigo carmine—was employed in over 75% of colonoscopies, and all procedures were performed using HD technology. This underscores the high quality and reliability of surveillance colonoscopies in our study, in line with quality guidelines. Strengths and Limitations Our study has several strengths. It was a randomized, controlled, multicentre trial conducted in regional hospitals, most with dedicated high-risk digestive cancer clinics. All patients met the updated 2019 SPS WHO criteria I or II, making this the first prospective study to apply these definitions, and underwent high-quality endoscopic procedures, ensuring reliable results. Nonetheless, there are limitations. The study was conducted only in Spain, with a higher proportion of patients fulfilling SPS criterion II than in previous cohorts. Follow-up was restricted to a single surveillance round of 2 or 3 years, limiting conclusions on long-term AN incidence. Moreover, the post hoc power analysis yielded a statistical power of only 33.8%, well below the commonly accepted 80% threshold, indicating a low probability of detecting true effects in this sample, largely due to patient loss in the 3-year group and reflecting an underestimated sample size. Conclusion In conclusion, extending endoscopic surveillance to three years in patients with SPS could not be demonstrated as non-inferior to the standard two-year strategy for AN detection. Although some authors suggest longer intervals for selected patients, our results could not currently support this approach. Patients with SPS continue to carry an elevated risk of AN or CRC during follow-up, although lower than previously reported. This risk is greatest in the initial years after SPS diagnosis, and our findings indicate it may decrease beyond the third year. Such a trend could support a de-intensified surveillance strategy for selected subgroups, especially in these low-risk patients without advanced neoplasia and with fewer than 5 relevant lesions in the last colonoscopy. However, additional long-term studies and adequately powered randomize controlled trials, with multiple surveillance rounds, are necessary to more accurately define the cumulative risk under the revised 2019 SPS WHO criteria. Abbreviations AA advanced adenoma AN advanced neoplasia CI confidence interval CRC colorectal cancer HD high definition HP hyperplastic polyps OR odds ratio SPS serrated polyposis syndrome SP serrated polyps SSL sessile serrated lesions TSA traditional serrated adenomas WHO World Health Organization Declarations Disclosures : all authors have no conflicts of interest to disclose. Data Transparency Statement : data, analytic and study materials will not be made available to other researchers. Ethics approval: the study complied with the Declaration of Helsinki, was approved by ethics committees ( Comité ético de investigación del Hospital Universitario de Móstoles. ID: 2021/005 ). 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Am J Gastroenterol . 2024;119(9):1754–1780. doi: 10.14309/ajg.0000000000002972 Ferlitsch M, Hassan C, Bisschops R, et al. Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024. Endoscopy . 2024;56(7):516–545. doi: 10.1055/a-2304-3219 Tables Table 1. Baseline patient and procedures characteristics by surveillance group Group A (2 years) Group B (3 years) SPS WHO criteria (%): II I I+II 63.9 15.3 20.8 71.2 15.3 13.6 Women (%) 55.6 37.3 Age (years) 67.1 64.9 Smoking history (%) never current former 15.3 36.1 48.8 18.5 39.0 42.5 Personal history of CRC (%) 8.3 6.8 Partial colectomy (%) 9.7 6.8 Median number of colonoscopies before randomization 6.5 6.4 Median number of colonoscopies after the clearing phase 2.8 2.9 Patients with previous AA (%) 36.6 43.1 Patients with previous advanced SP (%) 59.2 55.2 Years after diagnosis of SPS (median) 4.7 5.2 SPS: serrated polyposis syndrome. WHO: world health organization. CRC: colorectal cancer. AA: advanced adenoma. SP: serrated polyps. Table 2. Polyp characteristics in all colonoscopies by surveillance group Group A (2 years) Group B (3 years) p (sig<0.05) Histology Total polyps Normal tissue HP SSL without dysplasia SSL with dysplasia Adenoma LGD Adenoma HGD CRC 412 59 (14.2%) 205 (49.3%) 44 (10.6%) 0 (0%) 104 (25.0%) 0 (0%) 0 (0%) 347 81 (23.1%) 171 (48.9%) 26 (7.4%) 4 (1.1%) 65 (18.6%) 0 (0%) 0 (0%) 0.002 Advanced polyps Total polyps with histology Advanced adenomas Advanced serrated polyps Advanced neoplasia Relevant polyps 353 0 (0%) 6 (1.7%) 6 (1.7%) 170 (48.2%) 266 1 (0.4%) 8 (3.0%) 9 (3.4%) 119 (44.7%) 0.249 0.279 0.177 0.398 Location Total polyps with histology Ascending colon Transverse colon Descending colon Sigmoid colon Rectum 353 79 (22.4%) 89 (25.2%) 64 (18.1%) 88 (24.9%) 33 (9.3%) 266 42 (15.8%) 73 (27.4%) 38 (14.3%) 66 (24.8%) 47 (17.7%) 0.011 Morphology (Paris classification) Total polyps with histology 0-Is 0-Ip 0-IIa 0-IIb 0-IIc 0-III 353 24 (6.8%) 0 (0%) 278 (78.8%) 51 (14.4%) 0 (0%) 0 (0%) 266 27 (10.2%) 0 (0%) 218 (78.8%) 21 (7.9%) 0 (0%) 0 (0%) 0.020 Mean size (SD) mm. 3.7 (1.9) 3.8 (1.6) 0.819 Number of polyps per colonoscopy (mean) 5.9 5.3 0.336 Total time of colonoscopy (minutes) 28.2 26.3 0.297 Withdrawal time during colonoscopy (minutes) 22.5 20.6 0.267 CRC: colorectal cancer; HGD: high-grade dysplasia; HP: hyperplastic polyp; LGD: low-grade dysplasia; SSL: sessile serrated lesion. SD: standard deviation. Table 3. Predictors of advanced neoplasia and relevant polyps using univariate analysis Advanced neoplasia Relevant polyps OR (95%CI) p value OR (95%CI) p value Gender (male) 1.05 (0.33-3.32) 0.929 1.72 (0.67-4.43) 0.259 Age (>65 years) 0.75 (0.24-2.36) 0.636 1.51 (0.57-3.99) 0.408 Smoking (former or current) 1.54 (0.39-6.21) 0.523 2.15 (0.74-6.40) 0.149 WHO criterion at study inclusion (I or I+II) 1.88 (0.59-5.97) 0.281 0.40 (0.13-1.26) 0.109 SPS diagnosis (<3 years) 7.06 (2.05-24.33) <0.001 2.12 (1.00-4.49) 0.048 Colonoscopies after clearing phase (5) 0.57 (0.18-1.79) 0.330 1.28 (0.50-3.30) 0.617 Personal history of CRC (yes) 0.89 (0.70-1.44) 0.275 0.53 (0.06-4.40) 0.550 Previous advanced adenoma (yes) 1.60 (0.49-5.27) 0.436 1.87 (0.73-4.79) 0.188 Previous advanced SP (yes) 4.14 (0.87-19.73) 0.056 2.08 (0.75-5.76) 0.154 WHO: world Health Organization; SPS: serrated polyposis syndrome; CRC: colorectal cancer; SP serrated polyps Table 4. Multivariate logistic regression for advanced neoplasia and relevant polyps Variable for advanced neoplasia Univariate analysis Multivariate analysis OR (95%CI) p value OR (95%CI) p value SPS diagnosis (<3 years) 7.06 (2.05-24.33) <0.001 4.38 (1.52-14.75) 0.024 Colonoscopy after clearing phase (<2) 3.11 (1.05-9.58) 0.036 1.91 (0.28-13.26) 0.513 Previous advanced SP (yes) 4.14 (0.87-19.73) 0.056 2.64 (0.52-13.43) 0.242 Variable for relevant polyps Univariate analysis Multivariate analysis OR (95%CI) p value OR (95%CI) p value Smoking (former or current) 2.15 (0.74-6.41) 0.149 1.79 (0.65-4.43) 0.196 WHO criterion at study inclusion (I or I+II)) 0.40 (0.13-1.26) 0.109 0.88 (0.17-2.33) 0.463 SPS diagnosis (<3 years) 2.12 (1.00-4.49) 0.048 2.05 (1.19-3.94) 0.033 Colonoscopy after clearing phase (<2) 1.66 (0.77-3.56) 0.191 1.22 (0.30-3.15) 0.784 Previous advanced adenoma (yes) 1.87 (0.73-4.79) 0.188 1.75 (0.69-5.25) 0.263 Previous advanced SP (yes) 2.076 (0.75-5.76) 0.154 1.87 (0.71-4.21) 0.206 WHO: world Health Organization; SPS: serrated polyposis syndrome; CRC: colorectal cancer; SP: serrated polyps. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 21 Apr, 2026 Read the published version in Digestive Diseases and Sciences → Version 1 posted Editorial decision: Revision requested 04 Feb, 2026 Reviews received at journal 01 Feb, 2026 Reviews received at journal 31 Jan, 2026 Reviewers agreed at journal 25 Jan, 2026 Reviewers agreed at journal 24 Jan, 2026 Reviewers agreed at journal 21 Jan, 2026 Reviewers agreed at journal 21 Jan, 2026 Reviewers invited by journal 21 Jan, 2026 Editor assigned by journal 21 Jan, 2026 Submission checks completed at journal 19 Jan, 2026 First submitted to journal 19 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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2","display":"","copyAsset":false,"role":"figure","size":86539,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version.\u003c/p\u003e","description":"","filename":"Fig2.jpeg.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8642140/v1/00655643ba4fff68f0cbd126.jpeg"},{"id":101170957,"identity":"73124bec-979f-40cf-a646-cefd36e5c01e","added_by":"auto","created_at":"2026-01-27 00:05:41","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":55009,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version.\u003c/p\u003e","description":"","filename":"Fig3.jpeg.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8642140/v1/4fd87df252a421cc87a00653.jpg"},{"id":107928196,"identity":"3d0ed6f3-dfc9-44cc-834e-166c0ec65fda","added_by":"auto","created_at":"2026-04-27 16:09:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":626064,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8642140/v1/a98d0a34-3acd-4a6d-b6a3-e0cc0e1825ac.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Endoscopic Surveillance in Serrated Polyposis Syndrome: Two or Three-Year Intervals. A Noninferiority Randomized Trial","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eSerrated polyposis syndrome (SPS) is the most prevalent colorectal polyposis syndrome, ranging from 0.31% to 0.80% in faecal occult blood test or faecal immunochemical test-based screening programs and from 0.1% to 0.4% in colonoscopy-based programs[1][2] [3] [4]. \u0026nbsp;SPS is characterized by the presence of multiple colonic serrated polyps (SP), including hyperplastic polyps (HP), sessile serrated lesions (SSL) and traditional serrated adenomas (TSA). Diagnosis is based on clinical criteria established by the World Health Organization (WHO). The fifth edition of the \u003cem\u003eWHO\u003c/em\u003e \u003cem\u003eClassification of Tumours of the Digestive System\u003c/em\u003e, published in July 2019, defines SPS by either of the following criteria: Criterion I, ≥5 SP proximal to the rectum, all ≥5 mm in size, with at least 2 being ≥10 mm; or Criterion II, \u0026gt;20 SP of any size distributed throughout the large bowel, with at least 5 located proximal to the rectum[5] [6].\u003c/p\u003e\n\u003cp\u003eSPS is associated with an increased risk of colorectal cancer (CRC) compared to the general population. Two large cohort studies have estimated a wide range of CRC incidence, from 15% to 29%[7] [8]. A 2022 meta-analysis reported an overall CRC risk of 19% (95% CI, 15.3%–24.5%), with higher rates at the time of or prior to SPS diagnosis (14.7% [95% CI, 11.4%–18.8%] and 7% [95% CI, 4.5%–10.7%], respectively)[9]. However, the CRC incidence during surveillance appears lower than initially described, with a reported rate of 2.8% (95% CI, 1.8%–4.4%)[9] [10].\u003c/p\u003e\n\u003cp\u003eOnce SPS is diagnosed, all polyps ≥5 mm or with dysplastic appearance (adenoma, SSL or TSA) must be resected. Ideally, this should be achieved via polypectomy, although surgical resection may be required if the polyp burden cannot be managed endoscopically. After this clearing phase, close endoscopic surveillance is required. Long-term studies report a 5-year cumulative incidence of advanced neoplasia (AN)—CRC, advanced adenomas (AA), or advanced SP—of 21.6%–44% during surveillance and after de clearance phase [11] [12] [13][14]. In a prospective cohort of 142 patients with a 10-year follow-up and regular colonoscopy (1–2 years), only one CRC case was detected. In this study, the incidence of AN at different surveillance rounds remained below 16%[14]. Risk factors identified for CRC or AN include smoking, proximal SSL, SP with dysplasia, AA, advanced SP, and SPS 2010 WHO criterion I[13]. These data had led to the proposal of personalized surveillance based on individual risk.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDue to limited evidence, surveillance recommendations differ across countries and scientific societies. The U.S. Multi-Society Task Force in 2012 advised annual colonoscopy [15], the American College of Gastroenterology in 2015 suggested 1–3 years[16], the Spanish Society of Gastroenterology in 2018 proposed 1–3 years[17] and the British Society of Gastroenterology in 2020 recommended 1–2 years surveillance[18], based on histology and the size of lesions detected during last colonoscopy. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe 2019 European Society of Gastrointestinal Endoscopy (ESGE) guideline on endoscopic management of polyposis syndromes, recommends surveillance intervals based on the findings of the most recent colonoscopy: 1 year after resection of ≥1 advanced polyp or ≥5 relevant non-advanced polyps (adenomas, SSL, TSA or HP ≥5 mm), and 2 years otherwise (strong recommendation and low quality of evidence)[19]. A prospective multicentre study of 271 patients with SPS (median follow-up 3.6 years) supported these recommendations, showing AN incidence of 15.6% with biennial vs 24.4% with annual surveillance (OR 0.57, 95% CI, 0.31–1.07; p=0.08). Only two CRC cases occurred, yielding 5-year incidence of 1.3%, while the 5-year cumulative AN incidence was 44% (95% CI, 37%–52%). SPS WHO criterion I conferred higher AN risk than criterion III (2010 WHO criteria), whereas other factors were not significant. Notably, patients who had undergone prior surveillance colonoscopy before enrolment had lower risk of AN (HR 0.64, 95% CI, 0.41–0.99; p=0.047)[20].\u003c/p\u003e\n\u003cp\u003eSince biennial surveillance is not associated with increased AN, extending intervals beyond 2 years may be safe, effective and could alleviate the burden on endoscopy units. We therefore designed a non-inferiority randomized controlled trial to evaluate extended surveillance intervals in patients with SPS, specifically in individuals without advanced polyps or with fewer than five relevant polyps in their last colonoscopy. Patients were randomized to undergo colonoscopy at either two years or three years, and the primary outcome was the incidence of AN in each group.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003e\u003cstrong\u003eStudy Design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis multicentre randomized controlled trial (1:1) was conducted from May 2021 to November 2024 in six Spanish hospitals, five with high-risk digestive cancer clinics. Patients fulfilling 2019 SPS WHO criteria and under surveillance were randomized to colonoscopy at 2 years (group A) or 3 years (group B). Randomization was performed and data were collected for all centres via the online database REDCap (Research Electronic Data Capture), an electronic data capture tool hosted by the Spanish Society of Digestive Endoscopy (SEED; www.wseed.es)[21]. The study complied with the Declaration of Helsinki, was approved by ethics committees (\u003cem\u003eComité ético de investigación del Hospital Universitario de Móstoles. ID: 2021/005\u003c/em\u003e) and registered at ClinicalTrials.gov (NCT04906343). Written informed consent was obtained from all individual participants included in the study. All authors had access to the study data and approved the final manuscript. This research was supported by a grant from the Spanish Society of Digestive Endoscopy Foundation (FSEED) in November 2021.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInclusion and Exclusion Criteria\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEligible patients were aged ≥18 years with 2019 SPS WHO criteria I, II or both, having completed the clearing phase, and with \u0026lt;5 relevant polyps and no advanced polyps at last colonoscopy. \u0026nbsp;Thus, all patients had a recommended two-year surveillance interval according to ESGE guidelines before randomization[19]. Adequate bowel preparation (Boston Bowel Preparation Scale (BBPS) ≥2 in all segments[22]\u0026nbsp;and cecal intubation in prior colonoscopy were required.\u003c/p\u003e\n\u003cp\u003eExclusion criteria were patients with inflammatory bowel disease, other hereditary CRC syndromes (e.g., familial adenomatous polyposis, Lynch syndrome, Peutz-Jeghers syndrome, Cowden syndrome, juvenile polyposis syndrome), total colectomy, a piecemeal-resected lesion or invasive cancer at previous colonoscopy, and colonoscopy outside the scheduled window (±3 months).\u003c/p\u003e\n\u003cp\u003eDefinitions:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eAdvanced polyps: AA or advanced SP.\u003c/li\u003e\n \u003cli\u003eRelevant polyps: SSL or adenomas (any size), TSA or HP ≥5 mm.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003eClearing phase: resection of polyps ≥5 mm or with dysplasia (adenomas, TSA, SSL)[19].\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eClinical and Demographic Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCollected variables were age, sex, smoking history, SPS criteria, personal CRC history, prior surgery, history of AA or advanced SP, and number of surveillance colonoscopies after clearing phase.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eColonoscopy Procedures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHigh-definition (HD) endoscopes were used in all procedures, with chromoendoscopy, virtual chromoendoscopy or white light at endoscopist discretion. Bowel preparation protocols followed each centre’s standard practice and an adequate bowel preparation was defined as BBPS ≥2 in all segments[22]. Sedation was administered at the discretion of the endoscopist or anaesthesiologist. Polyps were classified according to the Paris morphology classification[23]. Location, size, and resection technique were recorded. Complications, including bleeding, perforation, or cardiorespiratory events occurring during the procedure or within the first month afterward, were documented. Only events requiring endoscopic intervention, hospitalization, or surgery were recorded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHistopathology\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTissue specimens were processed by gastrointestinal pathologists using the Vienna classification for gastrointestinal epithelial neoplasia[24]. Invasive cancer was defined as neoplastic extension into the submucosa or beyond. Polyp classification was based on WHO criteria[25]:\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003eSP: HP, SSL (with or without dysplasia) and TSA.\u003c/li\u003e\n \u003cli\u003eAA: Adenomas ≥10 mm, villous component and/or with high-grade dysplasia.\u003c/li\u003e\n \u003cli\u003eAdvanced SP: SP \u0026gt;10 mm and/or with dysplasia.\u003c/li\u003e\n \u003cli\u003eAN: Includes AA, Advanced SP and CRC.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eStudy Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePrimary: compare AN incidence between 2- and 3-year groups with a non-inferiority analysis.\u003c/p\u003e\n\u003cp\u003eSecondary: compare relevant polyps incidence, identify risk factors for AN and changes in surveillance recommendations based on ESGE guidelines.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSample Size Calculation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBased on a Dutch study by Bleijenberg et al., reporting a 15.6% AN incidence at two-year colonoscopy in low risk-patients [20], the noninferiority margin between the 2 years interval and the 3 years strategy was set to +10%. A total of 136 patients (68 per group) were required to achieve 80% power (β=0.2) to demonstrate non-inferiority, with a one-sided 0.025 contrast (type I error) and a 5% significance level, accounting for 10% expected losses.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analyses were performed using the Statistical Package for the Social Sciences (SPSS), version 25.0 for Windows (IBM Corp., 2012. NY: IBM Corp., USA). Quantitative variables were expressed in mean and standard deviation (±SD) and qualitative variables were expressed in frequency (%). In the noninferiority analysis a 1-sided confidence interval approach was used, with a preestated margin of non-inferiority (Δ) of +10%.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTwo-stage analyses were performed using Fisher's test, χ2 test, and multiple logistic regression analysis to identify the variables that predicted AN. Factors reaching p\u0026lt;0.20 in univariate analysis were analysed using a multivariate logistic regression test. Univariate analysis and multivariate logistic regression results were summarized as the odds ratio (OR) with 95% confidence interval (CI) for the OR. A p-value \u0026lt;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cstrong\u003ePatient Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 145 patients were enrolled in the study, 74 randomized to 2-year follow-up colonoscopy (Group A) and 71 to 3-year follow-up (Group B). The study flow-chart following the Consolidated Standards of Reporting Trials (CONSORT) guidelines is presented in Figure 1. Fourteen patients were excluded after randomization: 4 due to inadequate bowel preparation and 10 because they were lost in follow-up or underwent colonoscopy outside surveillance window (4% in the 2-year and 16.9% in the 3-year group). This left 131 patients for the data analysis, 72 in Group A and 59 in Group B.\u003c/p\u003e\n\u003cp\u003eMean age was 66.1 years (range 33.4–79.6), and 47.3% were women. At inclusion, 20 patients (15.3%) met WHO criterion I, 88 (67.2%) criterion II, and 23 (17.5%) both. Ten patients (7.6%) had a prior history of CRC.\u003c/p\u003e\n\u003cp\u003eSPS diagnosis was established a mean of 4.9 years before inclusion (range 1–11). Patients had a median of 6.5 colonoscopies (range 2–22) before enrolment, and 2.9 surveillance procedures after the clearing phase (range 0–7). Only 7 patients (5.3%) were randomized immediately after the clearing phase, while 105 (80.2%) had ≥2 surveillance colonoscopies before randomization. Baseline characteristics of patients by group are detailed in table 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eProcedures and Adverse Events\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures used HD technology. Virtual chromoendoscopy was applied in 30 cases (23.8%), chromoendoscopy with indigo carmine in 69 (53.1%), and white light alone in 30 (23.1%). No adverse events as bleeding, perforation or cardiopulmonary complications were reported. Procedure duration and withdrawal time were similar between groups (table 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLesions and Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAcross 124 patients, 771 polyps were resected, and 7 patients had no lesion. Twelve polyps lacked histology, and 140 (18.3%) were normal tissue, leaving 619 lesions for analysis. The morphological and histological characteristics of polyps are shown in table 2. Among these, 15 (2.4%) polyps were AN—6 in group A (1.7%) and 9 in group B (3.4%), p=0.177. Fourteen were advanced SP and one was an AA; no CRC was detected.\u003c/p\u003e\n\u003cp\u003eRelevant polyps (SSL, adenomas, TSA or HP ≥5 mm) accounted for 289 (46.7%): 170 (48.2%) in group A and 119 (44.7%) in group B, p=0.398. Mean polyp size was similar between the two groups: 3.74 mm (95% CI: 3.52–3.94) vs 3.77 mm (95% CI: 3.57–3.96), p=0.819; as the mean number of polyps per colonoscopy 5.9 (95% CI: 5.1–6.8) vs 5.3 (95% CI: 4.4–6.3), p=0.336, group A and group B respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe overall incidence of patients with at least one AN was 9.9% (95% CI, 4.8–15.1%), with 5/72 patients (6.9%) in group A and 8/59 (13.6%) in group B, p=0.208. The risk difference was +6.7% (95% CI, –4.1 to 17.5; p=0.27). Since the upper bound of the confidence interval exceeds the pre-specified noninferiority margin of +10%, non-inferiority of the 3-year strategy could not be established. Therefore, results regarding noninferiority analysis are inconclusive. Figure 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePatients with ≥5 relevant polyps were 18.1% in group A vs 15.3% in group B, with no statistical difference (OR 0.81, 95% CI, 0.32–2.07; p=0.670).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAccording to ESGE polyposis guideline recommendations, 30/131 patients (22.9%) should return to a 1-year surveillance interval, due to the detection of at least one advanced polyp or ≥5 relevant polyps, with no difference between groups (22.2% in group A vs 23.7% in group B, p=0.838); Figure 3.\u003c/p\u003e\n\u003cp\u003eA post hoc power analysis yielded a statistical power of 33.8%.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAssociation between advanced neoplasia and patient characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTable 3 shows associations between patient variables and AN. In univariate analysis, shorter time since SPS diagnosis and fewer number of colonoscopies after the clearing phase significantly predicted AN. Patients diagnosed from SPS \u0026lt;3 years had a 7.1-fold higher risk (95% CI, 2.05–24.33; p\u0026lt;0.001), and those with \u0026lt;2 colonoscopies after clearing phase had a 3.1-fold higher risk (95% CI, 1.05–9.58; p=0.036). A history of advanced SP also suggested increased risk of AN (OR 4.1, 95%CI, 0.87–19.73; p=0.056), but not reaching statistical significance.\u003c/p\u003e\n\u003cp\u003eIn multivariate analysis (table 4), only time since SPS diagnosis remained an independent predictor of AN: patients diagnosed from SPS \u0026lt;3 years had 4.4-fold greater risk (95% CI, 1.52–14.75; p=0.024).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAssociation between relevant polyps and patient characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe statistical analyses of predictors for relevant polyps are presented in table 3. In univariate analysis, time since SPS diagnosis was a significant predictor of relevant polyps: patients diagnosed \u0026lt;3 years had 2.12-fold higher risk (95% CI, 1.01–4.41; p=0.048).\u003c/p\u003e\n\u003cp\u003eIn multivariate analysis (table 4), time since SPS diagnosis remained a significant predictor for relevant polyps: patients diagnosed \u0026lt;3 years had 2.05-fold greater risk (95% CI, 1.19–3.94; p=0.033).\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eIn this randomized multicentre trial, non-inferiority of the 3-year follow-up strategy could not be established. The incidences of AN in the surveillance colonoscopy (6.9% in 2-year group vs 13.6% in 3-year group) were lower than expected based on previous literature. It is important to highlight that, in our study, patients did not present advanced lesions on the previous colonoscopy; therefore, they could be considered a low-risk group for AN. Bleijenberg et al., in a single-centre cohort of patients with SPS with a prospective 10-year follow-up and surveillance intervals of either 1 or 2 years, reported a relatively stable incidence of AN ranging from 8.7% to 24.2%[14]. Another single-centre cohort from Spain reported a 3-year cumulative AN incidence at 12.1% in 109 monitored patients, which aligns with our cohort [13]. The largest prospective study, involving 271 patients with SPS with a median follow-up of 3.6 years, described a cumulative AN incidence of 44% at five years[20]. This study suggested that AN incidence declines after surveillance, with lower risk in patients who had at least one prior colonoscopy (HR 0.64, 95% CI: 0.41 to 0.99, p=0.047). In that cohort, 31% of patients had prior follow-up, whereas 69% underwent their first surveillance colonoscopy after inclusion. In our study, only 7 patients (5.3%) had their first surveillance colonoscopy after inclusion—considerably lower than in the Bleijenberg study. Even more, 105 of 131 patients (80.2%) had undergone at least two surveillance colonoscopies after the clearing phase. In univariate analysis, patients with fewer than two colonoscopies after the clearing phase had over threefold higher AN risk, even though this association was not confirmed in multivariable analysis. Moreover, in our study, time since SPS diagnosis was also associated with AN detection at surveillance colonoscopy. Our findings suggest that patients with longer follow-up, longer interval since SPS diagnosis and more colonoscopies after the clearing phase have a lower risk of developing AN. Given that most participants were already under prolonged surveillance before enrolment and had no advanced lesions in their last colonoscopy, these two factors may explain the slightly lower incidence of AN observed in our cohort.\u003c/p\u003e\n\u003cp\u003eSeveral risk factors have been linked to CRC and AN incidence in retrospective studies, including the presence of SP with dysplasia, previous AA or advanced SP, and fulfilling both SPS WHO criteria I and III (2019 criteria II)[7] [8] [12].\u0026nbsp;Although these retrospective studies included a large number of patients, their findings were not corroborated in a subsequent prospective study[14]. Our results did not establish a relationship between these risk factors and AN occurrence. Gender, smoking status, age, prior AN, and SPS WHO criteria were not associated with AN detection. However, patients with prior advanced SP had a higher proportion of AN compared to those without (13.5% vs 3.6%), a difference approaching statistical significance [OR: 4.14 (95%IC: 0.87-19.73), p=0.056]. While our sample size was relatively large, it may not have been sufficiently powered to detect associations between risk factors and AN.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMeeting 2019 SPS criteria I or I+II in our study was linked to nearly double the AN risk (14% vs 8%), but without statistical significance [OR: 1.88, (95% CI: 0.59–5.97), p=0.28]. These data are comparable with larger retrospective and prospective cohorts that found significant higher AN incidence in patients meeting criteria I or I+III (2019 criteria II)[13] [20].\u0026nbsp;However, those studies were mainly retrospective and focused on 5-year cumulative AN incidence, while ours assessed 2- and 3-year intervals. Our cohort also included more patients meeting only SPS criterion II (67.2%) compared to other studies (36.5–45.3%)[7] [20]. Perhaps with a larger cohort including more SPS criterion I patients, differences might reach significance, potentially confirming a higher AN risk in these individuals. Notably, the only meta-analysis on CRC risk in SPS found no differences across WHO criteria[9].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn our cohort, 10 of 131 patients (7.6%) had a history of CRC, lower than reported in the literature. A meta-analysis by Müller et al. estimated a 14.7% CRC risk prior to SPS diagnosis and 2.8% during surveillance[9]. No cases of CRC were detected at either the 2- or 3-year follow-up in our study, consistent with previous findings from two retrospective series: one including 60 patients (mean follow-up, 2.1 years) and another with 96 patients (median, 3.6 years), as well as a single-centre prospective study of 41 patients followed for 3.1 years, all of which reported no incident CRC cases[11] [26] [27] . In a Dutch prospective cohort (\u0026gt;10 years), only one CRC occurred, yielding a 5-year incidence of 1.0% (95% CI, 0–2.9%)[14]. These findings support the low risk of CRC during surveillance in patients with SPS, particularly with the use of HD-endoscopy and specialized endoscopist care.\u003c/p\u003e\n\u003cp\u003eIn recent years, greater awareness of SPS has enhanced early detection in screening programs and routine colonoscopies, allowing diagnosis as soon as WHO criteria are met and potentially preventing the development of advanced polyps. All participating centres in our study were secondary hospitals that do not receive patients from other institutions. This differs from specialized referral centres, where selection bias may lead to a higher proportion of aggressive SPS phenotypes and, consequently, increased AN incidence.\u003c/p\u003e\n\u003cp\u003eA total of 771 polyps were resected across 131 colonoscopies, with a mean of 5.9 polyps per procedure. In comparison, another long-term follow-up study[14] reported 1308 polypectomies across 447 colonoscopies, with a mean of 2.9 polyps per procedure. Most resected polyps in our study were small, distributed throughout the colon and with highest frequence in the transverse colon (28%). On the other hand, 18.3% of resected polyps were histologically normal tissue, data often not reported. This suggests that the high number of small polyps may have led to the resection of lesions that lacked histological abnormalities. Given that 67.2% of our patients met only SPS WHO criterion II and they typically present with numerous small polyps, this could have contributed to the high rate of small, non-advanced polyps and normal-tissue resections. Importantly, no carcinoma or high-grade dysplasia was detected in any colonoscopy.\u003c/p\u003e\n\u003cp\u003eThe absence of adverse events was likely due to the study’s sample size, which may not have been sufficient to capture such occurrences, and also to the high number of diminutive lesions resected. The estimated incidence of post-polypectomy bleeding in different series is approximately 0.6-1.8%[28], while perforation rates following colonic endoscopic mucosal resection range from 0.08% to 0.11%[29][30]. However, this does not negate the risks and inconveniences associated with colonoscopy surveillance, including the potential impact on patients' daily activities [30].\u003c/p\u003e\n\u003cp\u003eWithdrawal time was consistently high across procedures, with a mean ≥ 20 minutes in both groups. Chromoendoscopy—either virtual or with indigo carmine—was employed in over 75% of colonoscopies, and all procedures were performed using HD technology. This underscores the high quality and reliability of surveillance colonoscopies in our study, in line with quality guidelines.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStrengths and Limitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur study has several strengths. It was a randomized, controlled, multicentre trial conducted in regional hospitals, most with dedicated high-risk digestive cancer clinics. All patients met the updated 2019 SPS WHO criteria I or II, making this the first prospective study to apply these definitions, and underwent high-quality endoscopic procedures, ensuring reliable results.\u003c/p\u003e\n\u003cp\u003eNonetheless, there are limitations. The study was conducted only in Spain, with a higher proportion of patients \u0026nbsp;fulfilling SPS criterion II than in previous cohorts. Follow-up was restricted to a single surveillance round of 2 or 3 years, limiting conclusions on long-term AN incidence. Moreover, the post hoc power analysis yielded a statistical power of only 33.8%, well below the commonly accepted 80% threshold, indicating a low probability of detecting true effects in this sample, largely due to patient loss in the 3-year group and reflecting an underestimated sample size.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, extending endoscopic surveillance to three years in patients with SPS could not be demonstrated as non-inferior to the standard two-year strategy for AN detection. Although some authors suggest longer intervals for selected patients, our results could not currently support this approach. Patients with SPS continue to carry an elevated risk of AN or CRC during follow-up, although lower than previously reported. This risk is greatest in the initial years after SPS diagnosis, and our findings indicate it may decrease beyond the third year. Such a trend could support a de-intensified surveillance strategy for selected subgroups, especially in these low-risk patients without advanced neoplasia and with fewer than 5 relevant lesions in the last colonoscopy. However, additional long-term studies and adequately powered randomize controlled trials, with multiple surveillance rounds, are necessary to more accurately define the cumulative risk under the revised 2019 SPS WHO criteria.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eadvanced adenoma\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAN\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eadvanced neoplasia\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003econfidence interval\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCRC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ecolorectal cancer\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eHD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ehigh definition\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eHP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ehyperplastic polyps\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eodds ratio\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSPS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eserrated polyposis syndrome\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eserrated polyps\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSSL\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003esessile serrated lesions\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eTSA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003etraditional serrated adenomas\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eWHO\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eWorld Health Organization\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDisclosures\u003c/strong\u003e: all authors have no conflicts of interest to disclose.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Transparency Statement\u003c/strong\u003e: data, analytic and study materials will not be made available to other researchers.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval:\u003c/strong\u003e the study complied with the Declaration of Helsinki, was approved by ethics committees (\u003cem\u003eComité ético de investigación del Hospital Universitario de Móstoles. ID: 2021/005\u003c/em\u003e).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate:\u003c/strong\u003e written informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e: this research was supported by a grant from the Spanish Society of Digestive Endoscopy Foundation (FSEED) in November 2021.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e \u003cli\u003e\u003cspan\u003evan Herwaarden YJ, Verstegen MHP, Dura P, et al. 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Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024. \u003cem\u003eEndoscopy\u003c/em\u003e. 2024;56(7):516\u0026ndash;545. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1055/a-2304-3219\u003c/span\u003e\u003cspan address=\"10.1055/a-2304-3219\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1. Baseline patient and procedures characteristics by surveillance group\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003eGroup A (2 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003eGroup B (3 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eSPS WHO criteria (%):\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003cp\u003eI+II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e63.9\u003c/p\u003e\n \u003cp\u003e15.3\u003c/p\u003e\n \u003cp\u003e20.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e71.2\u003c/p\u003e\n \u003cp\u003e15.3\u003c/p\u003e\n \u003cp\u003e13.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eWomen (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e55.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e37.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e67.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e64.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eSmoking history (%)\u003c/p\u003e\n \u003cp\u003enever\u003c/p\u003e\n \u003cp\u003ecurrent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eformer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e15.3\u003c/p\u003e\n \u003cp\u003e36.1\u003c/p\u003e\n \u003cp\u003e48.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e18.5\u003c/p\u003e\n \u003cp\u003e39.0\u003c/p\u003e\n \u003cp\u003e42.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003ePersonal history of CRC (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e8.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003ePartial colectomy (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e9.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eMedian number of colonoscopies before randomization\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e6.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e6.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eMedian number of colonoscopies after the clearing phase\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003ePatients with previous AA (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e36.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e43.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003ePatients with previous advanced SP (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e59.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e55.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003eYears after diagnosis of SPS (median)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e4.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eSPS: serrated polyposis syndrome. WHO: world health organization. CRC: colorectal cancer. AA: advanced adenoma. SP: serrated polyps.\u003c/p\u003e\n\u003cp\u003eTable 2. Polyp characteristics in all colonoscopies by surveillance group\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eGroup A (2 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eGroup B (3 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003ep (sig\u0026lt;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHistology\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eTotal polyps\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eNormal tissue\u003c/p\u003e\n \u003cp\u003eHP\u003c/p\u003e\n \u003cp\u003eSSL without dysplasia\u003c/p\u003e\n \u003cp\u003eSSL with dysplasia\u003c/p\u003e\n \u003cp\u003eAdenoma LGD\u003c/p\u003e\n \u003cp\u003eAdenoma HGD\u003c/p\u003e\n \u003cp\u003eCRC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e412\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e59 (14.2%)\u003c/p\u003e\n \u003cp\u003e205 (49.3%)\u003c/p\u003e\n \u003cp\u003e44 (10.6%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e104 (25.0%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e347\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e81 (23.1%)\u003c/p\u003e\n \u003cp\u003e171 (48.9%)\u003c/p\u003e\n \u003cp\u003e26 (7.4%)\u003c/p\u003e\n \u003cp\u003e4 (1.1%)\u003c/p\u003e\n \u003cp\u003e65 (18.6%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdvanced polyps\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eTotal polyps with histology\u003c/p\u003e\n \u003cp\u003eAdvanced adenomas\u003c/p\u003e\n \u003cp\u003eAdvanced serrated polyps\u003c/p\u003e\n \u003cp\u003eAdvanced neoplasia\u003c/p\u003e\n \u003cp\u003eRelevant polyps\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e353\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e6 (1.7%)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e6 (1.7%)\u003c/p\u003e\n \u003cp\u003e170 (48.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e266\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1 (0.4%)\u003c/p\u003e\n \u003cp\u003e8 (3.0%)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e9 (3.4%)\u003c/p\u003e\n \u003cp\u003e119 (44.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.249\u003c/p\u003e\n \u003cp\u003e0.279\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.177\u003c/p\u003e\n \u003cp\u003e0.398\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLocation\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eTotal polyps with histology\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAscending colon\u003c/p\u003e\n \u003cp\u003eTransverse colon\u003c/p\u003e\n \u003cp\u003eDescending colon\u003c/p\u003e\n \u003cp\u003eSigmoid colon\u003c/p\u003e\n \u003cp\u003eRectum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e353\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e79 (22.4%)\u003c/p\u003e\n \u003cp\u003e89 (25.2%)\u003c/p\u003e\n \u003cp\u003e64 (18.1%)\u003c/p\u003e\n \u003cp\u003e88 (24.9%)\u003c/p\u003e\n \u003cp\u003e33 (9.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e266\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e42 (15.8%)\u003c/p\u003e\n \u003cp\u003e73 (27.4%)\u003c/p\u003e\n \u003cp\u003e38 (14.3%)\u003c/p\u003e\n \u003cp\u003e66 (24.8%)\u003c/p\u003e\n \u003cp\u003e47 (17.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMorphology\u003c/strong\u003e (Paris classification)\u003c/p\u003e\n \u003cp\u003eTotal polyps with histology\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0-Is\u003c/p\u003e\n \u003cp\u003e0-Ip\u003c/p\u003e\n \u003cp\u003e0-IIa\u003c/p\u003e\n \u003cp\u003e0-IIb\u003c/p\u003e\n \u003cp\u003e0-IIc\u003c/p\u003e\n \u003cp\u003e0-III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e353\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e24 (6.8%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e278 (78.8%)\u003c/p\u003e\n \u003cp\u003e51 (14.4%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e266\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e27 (10.2%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e218 (78.8%)\u003c/p\u003e\n \u003cp\u003e21 (7.9%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.020\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003eMean size (SD) mm.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e3.7 (1.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e3.8 (1.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e0.819\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003eNumber of polyps per colonoscopy (mean)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e5.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e5.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e0.336\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003eTotal time of colonoscopy (minutes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e28.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e26.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e0.297\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 150px;\"\u003e\n \u003cp\u003eWithdrawal time during colonoscopy (minutes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e22.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e20.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 128px;\"\u003e\n \u003cp\u003e0.267\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eCRC: colorectal cancer; HGD: high-grade dysplasia; HP: hyperplastic polyp; LGD: low-grade dysplasia; SSL: sessile serrated lesion. SD: standard deviation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 3.\u0026nbsp;Predictors of advanced neoplasia and relevant polyps using univariate analysis\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"686\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 194px;\"\u003e\n \u003cp\u003eAdvanced neoplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 190px;\"\u003e\n \u003cp\u003eRelevant polyps\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 302px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 53px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 133px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 56px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eGender (male)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.05 (0.33-3.32)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.929\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1.72 (0.67-4.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.259\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eAge (\u0026gt;65 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e0.75 (0.24-2.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.636\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1.51 (0.57-3.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.408\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eSmoking (former or current)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.54 (0.39-6.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.523\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2.15 (0.74-6.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.149\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eWHO criterion at study inclusion (I or I+II)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.88 (0.59-5.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.281\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0.40 (0.13-1.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.109\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eSPS diagnosis (\u0026lt;3 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e7.06 (2.05-24.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2.12 (1.00-4.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003eColonoscopies after clearing phase (\u0026lt;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e3.11 (1.05-9.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1.66 (0.77-3.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.191\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003ePrevious colonoscopy (\u0026gt;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e0.57 (0.18-1.79)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.330\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1.28 (0.50-3.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.617\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003ePersonal history of CRC (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e0.89 (0.70-1.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.275\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e0.53 (0.06-4.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.550\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003ePrevious advanced adenoma (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.60 (0.49-5.27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.436\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e1.87 (0.73-4.79)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.188\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 302px;\"\u003e\n \u003cp\u003ePrevious advanced SP (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e4.14 (0.87-19.73)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 133px;\"\u003e\n \u003cp\u003e2.08 (0.75-5.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 56px;\"\u003e\n \u003cp\u003e0.154\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eWHO: world Health Organization; SPS: serrated polyposis syndrome; CRC: colorectal cancer; SP serrated polyps\u003c/p\u003e\n\u003cp\u003eTable 4.\u0026nbsp;Multivariate logistic regression for advanced neoplasia and relevant polyps\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"815\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 331px;\"\u003e\n \u003cp\u003eVariable for advanced neoplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eUnivariate analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 201px;\"\u003e\n \u003cp\u003eMultivariate analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eSPS diagnosis (\u0026lt;3 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e7.06 (2.05-24.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e4.38 (1.52-14.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.024\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eColonoscopy after clearing phase (\u0026lt;2) \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e3.11 (1.05-9.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.91 (0.28-13.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.513\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003ePrevious advanced SP (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e4.14 (0.87-19.73)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e2.64 (0.52-13.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.242\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 331px;\"\u003e\n \u003cp\u003eVariable for relevant polyps\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eUnivariate analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" style=\"width: 201px;\"\u003e\n \u003cp\u003eMultivariate analysis\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003eOR (95%CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003ep value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eSmoking (former or current)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e2.15 (0.74-6.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.149\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.79 (0.65-4.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.196\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eWHO criterion at study inclusion (I or I+II))\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e0.40 (0.13-1.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.109\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e0.88 (0.17-2.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.463\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eSPS diagnosis (\u0026lt;3 years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e2.12 (1.00-4.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e2.05 (1.19-3.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003eColonoscopy after clearing phase (\u0026lt;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.66 (0.77-3.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.191\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.22 (0.30-3.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003ePrevious advanced adenoma (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.87 (0.73-4.79)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.188\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.75 (0.69-5.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.263\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 331px;\"\u003e\n \u003cp\u003ePrevious advanced SP (yes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e2.076 (0.75-5.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.154\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 141px;\"\u003e\n \u003cp\u003e1.87 (0.71-4.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.206\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eWHO: world Health Organization; SPS: serrated polyposis syndrome; CRC: colorectal cancer; SP: serrated polyps.\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"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":"polyp, vigilance, cancer, surveillance","lastPublishedDoi":"10.21203/rs.3.rs-8642140/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8642140/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSerrated polyposis syndrome, the most prevalent colonic polyposis, confers an increased colorectal cancer risk. Guidelines recommend close colonoscopy surveillance, but recent data suggest low neoplasia rates, supporting longer colonoscopy intervals.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAims:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCompare advanced neoplasia incidence between two- and three-year surveillance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA multicentre, randomized noninferiority trial was performed (May 2021–November 2024) in six Spanish hospitals. Patients meeting 2019 serrated polyposis syndrome WHO criteria I or II, with no advanced polyps and \u0026lt;5 relevant polyps at their previous colonoscopy, were randomized to surveillance at two or three years. The primary endpoint was advanced neoplasia incidence.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 131 patients with serrated polyposis syndrome were included (47.3% women; mean age 66.1). Seventy-two were assigned to 2-year and 59 to 3-year colonoscopy. Among 771 resected lesions, 2.4% were advanced adenomas or advanced serrated polyps; no colorectal cancer was detected. The proportion of patients with advanced neoplasia in the surveillance colonoscopy was 6.9% (2-year) vs 13.6% (3-year), with no statistical difference (p=0.208) but with a risk difference of +6.7% (95% CI: –4.1% to 17.5%) exceeding the pre-specified non-inferiority margin of +10%. Time since serrated polyposis syndrome \u0026nbsp;diagnosis \u0026lt;3 years was associated with advanced neoplasia (OR: 4.4; 95% CI: 1.52-14.75; p=0.024).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn patients with serrated polyposis syndrome, extending colonoscopy surveillance intervals to three years was not shown to be non-inferior to a two-year interval for advanced neoplasia incidence. The early years of follow-up after serrated polyposis syndrome diagnosis was identified as a risk factor for advanced neoplasia.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial registry\u003c/strong\u003e: ClinicalTrials.gov (NCT04906343). Date: 5-10-2021.\u003c/p\u003e","manuscriptTitle":"Endoscopic Surveillance in Serrated Polyposis Syndrome: Two or Three-Year Intervals. A Noninferiority Randomized Trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-27 00:05:36","doi":"10.21203/rs.3.rs-8642140/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-05T00:27:14+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-01T06:16:59+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-31T06:22:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"208797467445266352395383922658719078074","date":"2026-01-26T00:17:24+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"134584272571356444130936176554737930260","date":"2026-01-24T05:35:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"173134127016692056321972644265944419671","date":"2026-01-22T01:26:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"65304831394838203587892304531125396341","date":"2026-01-21T23:52:57+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-21T23:43:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-21T20:18:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-20T04:40:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"Digestive Diseases and Sciences","date":"2026-01-19T17:44:39+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":"360484f3-c8ce-41c8-83e5-71f1c48ef5b1","owner":[],"postedDate":"January 27th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-04-27T16:06:50+00:00","versionOfRecord":{"articleIdentity":"rs-8642140","link":"https://doi.org/10.1007/s10620-026-09843-4","journal":{"identity":"digestive-diseases-and-sciences","isVorOnly":false,"title":"Digestive Diseases and Sciences"},"publishedOn":"2026-04-21 15:59:56","publishedOnDateReadable":"April 21st, 2026"},"versionCreatedAt":"2026-01-27 00:05:36","video":"","vorDoi":"10.1007/s10620-026-09843-4","vorDoiUrl":"https://doi.org/10.1007/s10620-026-09843-4","workflowStages":[]},"version":"v1","identity":"rs-8642140","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8642140","identity":"rs-8642140","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}