Negative Pressure Suction in ERCP Brush Cytology: Assessing its Impact on Biliary Stricture Diagnostics

Negative Pressure Suction in ERCP Brush Cytology: Assessing its Impact on Biliary Stricture Diagnostics | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Negative Pressure Suction in ERCP Brush Cytology: Assessing its Impact on Biliary Stricture Diagnostics Huajie Ying，, Xiaodan Ying, Fangyan Lu, Feiyan huang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5395962/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective : To evaluate the effectiveness of negative pressure suction in improving the diagnostic yield of brush cytology for biliary strictures. Methods : We conducted a prospective study on 48 patients undergoing ERCP. Participants were divided into two groups: those undergoing standard brush cytology (CP group) and those with additional negative pressure suction (NP group). The diagnostic yield of brush cytology and liquid-based cytology were compared, with an emphasis on assessing the independent predictive value of negative pressure and CA125. Results : The application of negative pressure significantly improved the positive diagnosis rate of liquid-based cytology to 75%, compared to standard brush cytology. No significant correlations were found with the length of the biliary stricture. Multivariate analysis revealed negative pressure (OR: 5.4; 95% CI: 1.18–29; p = 0.034) and CA125 (OR: 4.80; 95% CI: 1.07–25.27; p = 0.047) as independent predictors. The predictive model achieved an AUC of 0.823, suggesting a substantial enhancement in diagnostic accuracy. Conclusions : Negative pressure suction in brush cytology presents as a superior technique for the diagnosis of biliary strictures, offering a safer and more efficacious alternative to invasive biopsy methods. biliary stricture brush cytology negative pressure suction ERCP Figures Figure 1 Figure 2 Introduction Cholangiocarcinoma (CCA) and other causes of biliary strictures pose significant diagnostic and therapeutic challenges within the realm of gastroenterology. Endoscopic retrograde cholangiopancreatography (ERCP) plays a pivotal role in the management of biliary diseases, offering both diagnostic and therapeutic capabilities.[ 1 ] One of the simplest and most cost-effective diagnostic tools employed during ERCP is brush cytology, which is instrumental in distinguishing malignant from benign biliary strictures. Despite its widespread use, the diagnostic yield of brush cytology remains suboptimal, with sensitivity rates for detecting malignancy reported to be less than 50% in many studies.[ 2 ] The limitations of current diagnostic modalities underscore the need for enhanced techniques that can improve the diagnostic accuracy for biliary strictures.[ 3 ] Advances in imaging and molecular diagnostics have contributed to this field, yet brush cytology remains a fundamental procedure due to its minimal invasiveness and ease of implementation. [ 4 ]The quest to improve the sensitivity of cytological diagnosis has led to the exploration of adjunctive methods, such as the application of negative pressure during brush cytology, with the aim of increasing cellular yield and diagnostic efficacy.[ 5 ] The present study seeks to address this gap by analyzing the impact of negative pressure suction on the diagnostic yield of brush cytology and liquid-based cytology for biliary strictures. By enhancing the quantity and quality of cellular material obtained, we hypothesize that the addition of negative pressure suction could significantly improve the positive diagnostic rate of cytological examinations, offering a promising avenue for better management of patients with biliary strictures. Materials and Methods Participants This prospective, randomized controlled trial was conducted at the First Affiliated Hospital,Zhejiang University School of Medicinebetween January 2023 and June 2023.Patients undergoing ERCP for the investigation of biliary strictures were eligible for inclusion. Inclusion criteria were adults (aged ≥ 18 years) with clinical and imaging findings suggestive of biliary strictures. Exclusion criteria included patients with known bleeding disorders, pregnancy, or those who declined to participate in the study.The protocol was approved by the Institutional Review Board (IRB) of our institution, and written informed consent was obtained from all participants. Intervention Participants were randomized into two groups using a computer-generated sequence: the standard brush cytology group (Control Group) and the brush cytology with negative pressure suction group (Intervention Group). In the Control Group, brush cytology was performed using a standard technique without suction. In the Intervention Group, negative pressure suction was applied during the brush cytology procedure. A10-mL syringe was attached to the cytology brush handle, allowing for continuous negative pressure during the brushing process. Data Collection The primary outcome measure was the diagnostic yield of brush cytology, defined as the proportion of procedures resulting in a positive diagnosis of malignancy or specific benign conditions based on cytological analysis. Secondary outcomes included the adequacy of the specimen for cytological evaluation and any procedure-related adverse events. Cytological specimens were prepared using both conventional smear techniques and liquid-based cytology. The slides were stained and reviewed by two experienced cytopathologists blinded to the group allocation, with discrepancies resolved by consensus.Thefollowingclinical data of the subjects were collected:sex, age, site of stricture, diagnosis, stenosis length, carbohydrate antigen 19 − 9 (CA19-9) level, carcinoembryonic antigen (CEA) level, total bilirubin, direct bilirubin. Statistical Analysis Data were analyzed using SPSS version 25.0 (IBM Corp., Armonk, NY, USA). Categorical variables were compared using the Chi-square test or Fisher’s exact test, as appropriate. Continuous variables were compared using the t-test or Mann-Whitney U test based on the distribution. A p-value < 0.05 was considered statistically significant. Results Patient Characteristics As shown in table 1, a total of 48 patients were included, with 20 in the negative group and 28 in the positive group. The gender distribution showed 71% male and 29% female participants. The average age was 65.73 years, with no significant difference in age distribution between the two groups (p = 0.39). Biomarker levels (AFP, CEA, CA125, CA199, total bilirubin, and direct bilirubin) also showed no significant differences between groups, indicating consistent baseline conditions. In terms of diagnosis, 67% of patients had cholangiocarcinoma (CCA) and 33% had non-CCA, with a significantly higher proportion of CCA in the positive group compared to the negative group (p = 0.038). There were no significant differences in the site, degree, and length of biliary strictures between groups, suggesting that the severity of strictures did not affect group assignment.In this study, the NP group, which utilized negative pressure suction technology, showed a higher positive diagnosis rate compared to the CP group that underwent standard brushing (Table 1, p = 0.002), suggesting that negative pressure suction may play a beneficial role in improving the positive diagnosis rate of biliary strictures. Table 1. Patient Characteristics Variable Overall, N = 48 Negative, N = 20 Positive, N = 28 p-value Group, n (%) 0.002 CP 21 (44%) 14 (70%) 7 (25%) NP 27 (56%) 6 (30%) 21 (75%) Sex, n (%) 0.59 Male 34 (71%) 15 (75%) 19 (68%) Female 14 (29%) 5 (25%) 9 (32%) Age, Mean (SD) 65.73 (12.57) 63.60 (13.52) 67.25 (11.85) 0.39 AFP, Mean (SD) 2.91 (1.69) 2.95 (1.58) 2.87 (1.79) 0.69 CEA, Mean (SD) 13.53 (45.56) 4.45 (2.73) 20.02 (59.19) 0.93 CA125.value, Mean (SD) 105.70 (438.71) 42.09 (55.20) 151.14 (572.50) 0.14 CA199, Mean (SD) 4,838.66 (17,313.01) 5,416.71 (19,812.16) 4,425.77 (15,656.53) 0.44 Total bilirubin, Mean (SD) 210.48 (167.33) 190.52 (187.34) 224.74 (153.41) 0.33 Direct bilirubin, Mean (SD) 183.51 (149.43) 167.88 (163.06) 194.68 (140.88) 0.37 Diagnosis, n (%) 0.038 Non-CCA 16 (33%) 10 (50%) 6 (21%) CCA 32 (67%) 10 (50%) 22 (79%) Site of stricture, n (%) 0.21 Lower segment of CBD 19 (40%) 10 (50%) 9 (32%) Middle or upper segment of CBD 29 (60%) 10 (50%) 19 (68%) Degree of stricture, n (%) 0.74 Severe 11 (23%) 4 (20%) 7 (25%) Mild or moderate 37 (77%) 16 (80%) 21 (75%) Length of stricture, n (%) 0.56 1.5 cm 45 (94%) 18 (90%) 27 (96%) Abbreviations: CBD, common bile duct; CCA, Cholangiocarcinoma. Model establishment by logistic analysis Spearman’s correlation analysis across 13 covariates showed no significant associations (Fig. 1 a). Univariate logistic analysis similarly found no significant correlations with pathology results from brush cytology. In contrast, liquid-based cytology results significantly correlated with cholangiocarcinoma, CA125, total bilirubin, direct bilirubin, and the application of negative pressure (p < 0.05, Fig. 1 b). Multivariate analysis confirmed negative pressure (OR: 5.4; 95% CI: 1.18–29; p = 0.034) and CA125 (OR: 4.80; 95% CI: 1.07–25.27; p = 0.047) as independent predictors (Fig. 3a). A derived predictive model, Y = 1.68 × (negative pressure) + 1.57 × (CA125) − 2.63, yielded an AUC of 0.823 (95% CI: 0.695–0.951, Fig. 3b). This model was presented as the nomogram (Fig. 3c), outperforming the individual AUCs for negative pressure and CA125, which indicates enhanced diagnostic accuracy for biliary strictures when these factors are combined (p < 0.05; Fig. 3b).The Hosmer-Lemeshow test showed a non-significant statistic, indicating excellent calibration of the model (Fig. 4d). Discussion This study reaffirms the effectiveness of negative pressure suction in brush cytology, increasing the positive detection rate for biliary strictures, which is crucial since pathology remains the definitive standard despite advances in imaging techniques.[ 6 ] While the diagnostic yields for MRCP and CT stand at 59.3%, and biliary biopsy combined with brush cytology at 59.4%,[ 7 ] the introduction of negative pressure in our study showed an enhancement in liquid-based cytology positive detection rates to 75%. The safety profile and procedural simplicity of brush cytology give it an advantage over more invasive methods like biliary and SpyBite biopsies, which carry a higher risk of complications or require significant training.[ 8 ] Our study suggests that the length of the stenotic segment does not correlate with the detection rate, counter to previous assumptions.[ 2 ] Negative pressure optimizes tissue collection efficiency, independent of stenotic segment length. Merging bile extraction with brushing, in contrast to separate procedures as done by Roth.[ 9 ] our study streamlines the diagnostic process. Moreover, liquid-based cytology addresses the limitations of traditional slide preparation by reducing the risk of contamination.[ 10 ] However, it should be noted that negative pressure can lead to the inadvertent adsorption of extraneous materials, potentially lowering the positive detection rate. Our technique simplifies the application of negative pressure in brush cytology, bypassing more complex methods like balloon dilatation or specialized brushes that have been investigated for their potential to improve detection rates.[ 11 , 12 ] The controlled bleeding observed post-brush cytology suggests a manageable safety profile for negative pressure application. Despite the promising results, the study's small sample size and the selection of relatively straightforward cases highlight the need for further research. Larger, more comprehensive studies are warranted to confirm these findings and optimize the negative pressure technique. The application of negative pressure in brush cytology represents an advancement in the minimally invasive diagnosis of biliary diseases. Future research should expand on this study's findings, employing larger and more diverse patient cohorts to consolidate the role of negative pressure suction as a mainstay in endoscopic diagnostics. Conclusion In summary, this study demonstrated that negative pressure is a simple, safe, and effective toolthat can improve the sensitivity of brush cytology through fluid analysis, thereby facilitatingthe diagnosis of biliary stenosis and increasing the successof subsequent treatment. Declarations Author Contribution ying and lu wrote the main manuscript text ，huang and yin Collect and organize data.All authors reviewed the manuscript References Wang J, Xia M, Jin Y, et al. More Endoscopy-Based Brushing Passes Improve the Detection of Malignant Biliary Strictures: A Multicenter Randomized Controlled Trial. Am J Gastroenterol. 2022. 117(5): 733-739. Kobayashi M, Ryozawa S, Araki R, et al. Investigation of Factors Affecting the Sensitivity of Bile Duct Brush Cytology. Intern Med. 2019. 58(3): 329-335. Kohli DR, Amateau SK, Desai M, et al. American Society for Gastrointestinal Endoscopy guideline on management of post-liver transplant biliary strictures: summary and recommendations. Gastrointest Endosc. 2023. 97(4): 607-614. Smoczynski M, Jablonska A, Matyskiel A, et al. Routine brush cytology and fluorescence in situ hybridization for assessment of pancreatobiliary strictures. Gastrointest Endosc. 2012. 75(1): 65-73. Fior-Gozlan M, Giovannini D, Rabeyrin M, Mc Leer-Florin A, Laverrière MH, Bichard P. Monocentric study of bile aspiration associated with biliary brushing performed during endoscopic retrograde cholangiopancreatography in 239 patients with symptomatic biliary stricture. Cancer Cytopathol. 2016. 124(5): 330-9. Wang GX, Ge XD, Zhang D, Chen HL, Zhang QC, Wen L. MRCP Combined With CT Promotes the Differentiation of Benign and Malignant Distal Bile Duct Strictures. Front Oncol. 2021. 11: 683869. Navaneethan U, Njei B, Lourdusamy V, Konjeti R, Vargo JJ, Parsi MA. Comparative effectiveness of biliary brush cytology and intraductal biopsy for detection of malignant biliary strictures: a systematic review and meta-analysis. Gastrointest Endosc. 2015. 81(1): 168-76. Navaneethan U, Hasan MK, Lourdusamy V, Njei B, Varadarajulu S, Hawes RH. Single-operator cholangioscopy and targeted biopsies in the diagnosis of indeterminate biliary strictures: a systematic review. Gastrointest Endosc. 2015. 82(4): 608-14.e2. Roth GS, Bichard P, Fior-Gozlan M, et al. Performance of bile aspiration plus brushing to diagnose malignant biliary strictures during endoscopic retrograde cholangiopancreatography. Endosc Int Open. 2016. 4(9): E997-E1003. Logrono R, Kurtycz DF, Molina CP, Trivedi VA, Wong JY, Block KP. Analysis of false-negative diagnoses on endoscopic brush cytology of biliary and pancreatic duct strictures: the experience at 2 university hospitals. Arch Pathol Lab Med. 2000. 124(3): 387-92. Karsenti D, Privat J, Charissoux A, et al. Multicenter randomized trial comparing diagnostic sensitivity and cellular abundance with aggressive versus standard biliary brushing for bile duct stenosis without mass syndrome. Endoscopy. 2023. 55(9): 796-803. Kylänpää L, Boyd S, Ristimäki A, Lindström O, Udd M, Halttunen J. A prospective randomised study of dense Infinity cytological brush versus regularly used brush in pancreaticobiliary malignancy. Scand J Gastroenterol. 2016. 51(5): 590-3. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5395962","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":377322164,"identity":"36971619-7df0-4ac5-8494-2e6dd1b6aaf1","order_by":0,"name":"Huajie Ying，","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA20lEQVRIie3RsQrCMBCA4QuFuES7xqV9hYiLoA9zIthJcOqcUujUBwg4+Ay+QUvAqXR2cKiTq2MdRK0OjombYP4tcB93EACX6wej4SlpsJ0FAEX3tCADWKTilC/H9iSAKBs2VM/le6nNYVBKjsyLtkkl4BJr8DfSQEgiBU7oKpGVIKrWwI+FgXhEIjK2SqESXj/TIDgaCCWyQMoj2pGbFWHPy5AKZB0hVoSTFOY5jhTs12VeR4wfDCRUvfO1be9hqPSuaeNp4CsD+cSL12cy2/lnvvxi2OVyuf6qB/04QkVds1t4AAAAAElFTkSuQmCC","orcid":"","institution":"Zhejiang University School of Medicine","correspondingAuthor":true,"prefix":"","firstName":"Huajie","middleName":"","lastName":"Ying，","suffix":""},{"id":377322165,"identity":"685233e4-e4aa-4f76-8c72-b87b78497011","order_by":1,"name":"Xiaodan Ying","email":"","orcid":"","institution":"Zhejiang University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Xiaodan","middleName":"","lastName":"Ying","suffix":""},{"id":377322166,"identity":"636a225a-8edb-4631-94c5-8d19345cb809","order_by":2,"name":"Fangyan Lu","email":"","orcid":"","institution":"Zhejiang University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Fangyan","middleName":"","lastName":"Lu","suffix":""},{"id":377322167,"identity":"d003acbf-2d9b-4091-aab3-a095c3bb81a0","order_by":3,"name":"Feiyan huang","email":"","orcid":"","institution":"Zhejiang University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Feiyan","middleName":"","lastName":"huang","suffix":""}],"badges":[],"createdAt":"2024-11-05 13:53:59","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5395962/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5395962/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71053342,"identity":"d4ad19fb-6cc5-4d8c-a74e-e6ff479f80f9","added_by":"auto","created_at":"2024-12-10 15:54:35","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":82729,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSpearman’s Correlation and Univariate Analysis of Biliary Stricture Diagnosis(a)\u003c/strong\u003e Heatmap displaying Spearman’s correlation coefficients between clinical and laboratory variables, with color intensity indicating correlation strength (red for positive, blue for negative). \u003cstrong\u003e(b)\u003c/strong\u003e Forest plot presenting odds ratios (OR) and 95% confidence intervals (CI) for variables associated with positive liquid-based cytology results. Red dots represent ORs, with horizontal lines depicting 95% CIs. Asterisks indicate statistical significance (*p \u0026lt; 0.05, **p \u0026lt; 0.01).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5395962/v1/da36da35ffd3847ccf79da53.png"},{"id":71053343,"identity":"93c25274-065c-45a5-a66b-d12d4d73f37d","added_by":"auto","created_at":"2024-12-10 15:54:35","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":221453,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMultivariate Analysis and Predictive Modeling for Biliary Stricture Diagnostics(a)\u003c/strong\u003e Forest plot of multivariate analysis depicting the odds ratios (OR) and 95% confidence intervals (CI) for each variable in predicting the outcome of liquid-based cytology. Group (NP) and high CA125 levels are shown as independent predictors. \u003cstrong\u003e(b)\u003c/strong\u003e Nomogram for predicting the probability of positive liquid-based cytology results based on the NP group and CA125 levels, where higher total points increase the likelihood of a positive diagnosis. \u003cstrong\u003e(c)\u003c/strong\u003e Receiver Operating Characteristic (ROC) curves illustrating the sensitivity and specificity of the predictive model, group classification, and CA125 level for predicting positive cytology outcomes. \u003cstrong\u003e(d)\u003c/strong\u003eCalibration plot for the predictive model, comparing the observed probability of positive diagnoses against the predicted probability, with the diagonal line representing perfect calibration.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5395962/v1/ca5064c23172a19db2ec569f.png"},{"id":72212714,"identity":"def595f8-f10a-4c4a-bc32-c5aa6fa8e78f","added_by":"auto","created_at":"2024-12-23 18:16:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":704153,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5395962/v1/cc8591cb-3b7b-4597-87c6-f82071e8ca05.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Negative Pressure Suction in ERCP Brush Cytology: Assessing its Impact on Biliary Stricture Diagnostics","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCholangiocarcinoma (CCA) and other causes of biliary strictures pose significant diagnostic and therapeutic challenges within the realm of gastroenterology. Endoscopic retrograde cholangiopancreatography (ERCP) plays a pivotal role in the management of biliary diseases, offering both diagnostic and therapeutic capabilities.[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] One of the simplest and most cost-effective diagnostic tools employed during ERCP is brush cytology, which is instrumental in distinguishing malignant from benign biliary strictures. Despite its widespread use, the diagnostic yield of brush cytology remains suboptimal, with sensitivity rates for detecting malignancy reported to be less than 50% in many studies.[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe limitations of current diagnostic modalities underscore the need for enhanced techniques that can improve the diagnostic accuracy for biliary strictures.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] Advances in imaging and molecular diagnostics have contributed to this field, yet brush cytology remains a fundamental procedure due to its minimal invasiveness and ease of implementation. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]The quest to improve the sensitivity of cytological diagnosis has led to the exploration of adjunctive methods, such as the application of negative pressure during brush cytology, with the aim of increasing cellular yield and diagnostic efficacy.[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe present study seeks to address this gap by analyzing the impact of negative pressure suction on the diagnostic yield of brush cytology and liquid-based cytology for biliary strictures. By enhancing the quantity and quality of cellular material obtained, we hypothesize that the addition of negative pressure suction could significantly improve the positive diagnostic rate of cytological examinations, offering a promising avenue for better management of patients with biliary strictures.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003eThis prospective, randomized controlled trial was conducted at the First Affiliated Hospital,Zhejiang University School of Medicinebetween January 2023 and June 2023.Patients undergoing ERCP for the investigation of biliary strictures were eligible for inclusion. Inclusion criteria were adults (aged\u0026thinsp;\u0026ge;\u0026thinsp;18 years) with clinical and imaging findings suggestive of biliary strictures. Exclusion criteria included patients with known bleeding disorders, pregnancy, or those who declined to participate in the study.The protocol was approved by the Institutional Review Board (IRB) of our institution, and written informed consent was obtained from all participants.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIntervention\u003c/h3\u003e\n\u003cp\u003eParticipants were randomized into two groups using a computer-generated sequence: the standard brush cytology group (Control Group) and the brush cytology with negative pressure suction group (Intervention Group). In the Control Group, brush cytology was performed using a standard technique without suction. In the Intervention Group, negative pressure suction was applied during the brush cytology procedure. A10-mL syringe was attached to the cytology brush handle, allowing for continuous negative pressure during the brushing process.\u003c/p\u003e\n\u003ch3\u003eData Collection\u003c/h3\u003e\n\u003cp\u003eThe primary outcome measure was the diagnostic yield of brush cytology, defined as the proportion of procedures resulting in a positive diagnosis of malignancy or specific benign conditions based on cytological analysis. Secondary outcomes included the adequacy of the specimen for cytological evaluation and any procedure-related adverse events. Cytological specimens were prepared using both conventional smear techniques and liquid-based cytology. The slides were stained and reviewed by two experienced cytopathologists blinded to the group allocation, with discrepancies resolved by consensus.Thefollowingclinical data of the subjects were collected:sex, age, site of stricture, diagnosis, stenosis length, carbohydrate antigen 19\u0026thinsp;\u0026minus;\u0026thinsp;9 (CA19-9) level, carcinoembryonic antigen (CEA) level, total bilirubin, direct bilirubin.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eData were analyzed using SPSS version 25.0 (IBM Corp., Armonk, NY, USA). Categorical variables were compared using the Chi-square test or Fisher\u0026rsquo;s exact test, as appropriate. Continuous variables were compared using the t-test or Mann-Whitney U test based on the distribution. A p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003ePatient Characteristics\u003c/h2\u003e\n \u003cp\u003eAs shown in table 1, a total of 48 patients were included, with 20 in the negative group and 28 in the positive group. The gender distribution showed 71% male and 29% female participants. The average age was 65.73 years, with no significant difference in age distribution between the two groups (p\u0026thinsp;=\u0026thinsp;0.39). Biomarker levels (AFP, CEA, CA125, CA199, total bilirubin, and direct bilirubin) also showed no significant differences between groups, indicating consistent baseline conditions. In terms of diagnosis, 67% of patients had cholangiocarcinoma (CCA) and 33% had non-CCA, with a significantly higher proportion of CCA in the positive group compared to the negative group (p\u0026thinsp;=\u0026thinsp;0.038). There were no significant differences in the site, degree, and length of biliary strictures between groups, suggesting that the severity of strictures did not affect group assignment.In this study, the NP group, which utilized negative pressure suction technology, showed a higher positive diagnosis rate compared to the CP group that underwent standard brushing (Table\u0026nbsp;1, p\u0026thinsp;=\u0026thinsp;0.002), suggesting that negative pressure suction may play a beneficial role in improving the positive diagnosis rate of biliary strictures.\u003c/p\u003e\n \u003cp\u003eTable 1. Patient Characteristics\u003c/p\u003e\n \u003ctable border=\"1\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eOverall, N = 48\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eNegative, N = 20\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePositive, N = 28\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eGroup, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21 (44%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14 (70%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27 (56%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6 (30%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21 (75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eSex, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e34 (71%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15 (75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19 (68%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14 (29%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9 (32%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e65.73 (12.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63.60 (13.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e67.25 (11.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.39\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAFP, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.91 (1.69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.95 (1.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.87 (1.79)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eCEA, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e13.53 (45.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.45 (2.73)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20.02 (59.19)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eCA125.value, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e105.70 (438.71)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e42.09 (55.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e151.14 (572.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eCA199, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4,838.66 (17,313.01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5,416.71 (19,812.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4,425.77 (15,656.53)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eTotal bilirubin, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e210.48 (167.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e190.52 (187.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e224.74 (153.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eDirect bilirubin, Mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e183.51 (149.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e167.88 (163.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e194.68 (140.88)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eDiagnosis, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.038\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNon-CCA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e16 (33%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6 (21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCCA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32 (67%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e22 (79%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eSite of stricture, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLower segment of CBD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19 (40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9 (32%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMiddle or upper segment of CBD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e29 (60%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19 (68%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eDegree of stricture, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11 (23%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMild or moderate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e37 (77%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e16 (80%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21 (75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eLength of stricture, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;1.5 cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (6.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 (10%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1 (3.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026gt;1.5 cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e45 (94%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e18 (90%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27 (96%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003eAbbreviations: CBD, common bile duct; CCA, Cholangiocarcinoma.\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eModel establishment by logistic analysis\u003c/h3\u003e\n\u003cp\u003eSpearman\u0026rsquo;s correlation analysis across 13 covariates showed no significant associations (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ea). Univariate logistic analysis similarly found no significant correlations with pathology results from brush cytology. In contrast, liquid-based cytology results significantly correlated with cholangiocarcinoma, CA125, total bilirubin, direct bilirubin, and the application of negative pressure (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eb). Multivariate analysis confirmed negative pressure (OR: 5.4; 95% CI: 1.18\u0026ndash;29; p\u0026thinsp;=\u0026thinsp;0.034) and CA125 (OR: 4.80; 95% CI: 1.07\u0026ndash;25.27; p\u0026thinsp;=\u0026thinsp;0.047) as independent predictors (Fig.\u0026nbsp;3a). A derived predictive model, Y\u0026thinsp;=\u0026thinsp;1.68 \u0026times; (negative pressure)\u0026thinsp;+\u0026thinsp;1.57 \u0026times; (CA125) \u0026minus;\u0026thinsp;2.63, yielded an AUC of 0.823 (95% CI: 0.695\u0026ndash;0.951, Fig.\u0026nbsp;3b). This model was presented as the nomogram (Fig.\u0026nbsp;3c), outperforming the individual AUCs for negative pressure and CA125, which indicates enhanced diagnostic accuracy for biliary strictures when these factors are combined (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05; Fig.\u0026nbsp;3b).The Hosmer-Lemeshow test showed a non-significant statistic, indicating excellent calibration of the model (Fig.\u0026nbsp;4d).\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study reaffirms the effectiveness of negative pressure suction in brush cytology, increasing the positive detection rate for biliary strictures, which is crucial since pathology remains the definitive standard despite advances in imaging techniques.[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] While the diagnostic yields for MRCP and CT stand at 59.3%, and biliary biopsy combined with brush cytology at 59.4%,[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] the introduction of negative pressure in our study showed an enhancement in liquid-based cytology positive detection rates to 75%.\u003c/p\u003e \u003cp\u003eThe safety profile and procedural simplicity of brush cytology give it an advantage over more invasive methods like biliary and SpyBite biopsies, which carry a higher risk of complications or require significant training.[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] Our study suggests that the length of the stenotic segment does not correlate with the detection rate, counter to previous assumptions.[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] Negative pressure optimizes tissue collection efficiency, independent of stenotic segment length.\u003c/p\u003e \u003cp\u003eMerging bile extraction with brushing, in contrast to separate procedures as done by Roth.[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] our study streamlines the diagnostic process. Moreover, liquid-based cytology addresses the limitations of traditional slide preparation by reducing the risk of contamination.[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] However, it should be noted that negative pressure can lead to the inadvertent adsorption of extraneous materials, potentially lowering the positive detection rate.\u003c/p\u003e \u003cp\u003eOur technique simplifies the application of negative pressure in brush cytology, bypassing more complex methods like balloon dilatation or specialized brushes that have been investigated for their potential to improve detection rates.[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] The controlled bleeding observed post-brush cytology suggests a manageable safety profile for negative pressure application.\u003c/p\u003e \u003cp\u003eDespite the promising results, the study's small sample size and the selection of relatively straightforward cases highlight the need for further research. Larger, more comprehensive studies are warranted to confirm these findings and optimize the negative pressure technique.\u003c/p\u003e \u003cp\u003eThe application of negative pressure in brush cytology represents an advancement in the minimally invasive diagnosis of biliary diseases. Future research should expand on this study's findings, employing larger and more diverse patient cohorts to consolidate the role of negative pressure suction as a mainstay in endoscopic diagnostics.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, this study demonstrated that negative pressure is a simple, safe, and effective toolthat can improve the sensitivity of brush cytology through fluid analysis, thereby facilitatingthe diagnosis of biliary stenosis and increasing the successof subsequent treatment.\u003c/p\u003e "},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eying and lu wrote the main manuscript text ，huang and yin Collect and organize data.All authors reviewed the manuscript\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eWang J, Xia M, Jin Y, et al. More Endoscopy-Based Brushing Passes Improve the Detection of Malignant Biliary Strictures: A Multicenter Randomized Controlled Trial. Am J Gastroenterol. 2022. 117(5): 733-739.\u003c/li\u003e\n\u003cli\u003eKobayashi M, Ryozawa S, Araki R, et al. Investigation of Factors Affecting the Sensitivity of Bile Duct Brush Cytology. Intern Med. 2019. 58(3): 329-335.\u003c/li\u003e\n\u003cli\u003eKohli DR, Amateau SK, Desai M, et al. American Society for Gastrointestinal Endoscopy guideline on management of post-liver transplant biliary strictures: summary and recommendations. Gastrointest Endosc. 2023. 97(4): 607-614.\u003c/li\u003e\n\u003cli\u003eSmoczynski M, Jablonska A, Matyskiel A, et al. Routine brush cytology and fluorescence in situ hybridization for assessment of pancreatobiliary strictures. Gastrointest Endosc. 2012. 75(1): 65-73.\u003c/li\u003e\n\u003cli\u003eFior-Gozlan M, Giovannini D, Rabeyrin M, Mc Leer-Florin A, Laverri\u0026egrave;re MH, Bichard P. Monocentric study of bile aspiration associated with biliary brushing performed during endoscopic retrograde cholangiopancreatography in 239 patients with symptomatic biliary stricture. Cancer Cytopathol. 2016. 124(5): 330-9.\u003c/li\u003e\n\u003cli\u003eWang GX, Ge XD, Zhang D, Chen HL, Zhang QC, Wen L. MRCP Combined With CT Promotes the Differentiation of Benign and Malignant Distal Bile Duct Strictures. Front Oncol. 2021. 11: 683869.\u003c/li\u003e\n\u003cli\u003eNavaneethan U, Njei B, Lourdusamy V, Konjeti R, Vargo JJ, Parsi MA. Comparative effectiveness of biliary brush cytology and intraductal biopsy for detection of malignant biliary strictures: a systematic review and meta-analysis. Gastrointest Endosc. 2015. 81(1): 168-76.\u003c/li\u003e\n\u003cli\u003eNavaneethan U, Hasan MK, Lourdusamy V, Njei B, Varadarajulu S, Hawes RH. Single-operator cholangioscopy and targeted biopsies in the diagnosis of indeterminate biliary strictures: a systematic review. Gastrointest Endosc. 2015. 82(4): 608-14.e2.\u003c/li\u003e\n\u003cli\u003eRoth GS, Bichard P, Fior-Gozlan M, et al. Performance of bile aspiration plus brushing to diagnose malignant biliary strictures during endoscopic retrograde cholangiopancreatography. Endosc Int Open. 2016. 4(9): E997-E1003.\u003c/li\u003e\n\u003cli\u003eLogrono R, Kurtycz DF, Molina CP, Trivedi VA, Wong JY, Block KP. Analysis of false-negative diagnoses on endoscopic brush cytology of biliary and pancreatic duct strictures: the experience at 2 university hospitals. Arch Pathol Lab Med. 2000. 124(3): 387-92.\u003c/li\u003e\n\u003cli\u003eKarsenti D, Privat J, Charissoux A, et al. Multicenter randomized trial comparing diagnostic sensitivity and cellular abundance with aggressive versus standard biliary brushing for bile duct stenosis without mass syndrome. Endoscopy. 2023. 55(9): 796-803.\u003c/li\u003e\n\u003cli\u003eKyl\u0026auml;np\u0026auml;\u0026auml; L, Boyd S, Ristim\u0026auml;ki A, Lindstr\u0026ouml;m O, Udd M, Halttunen J. A prospective randomised study of dense Infinity cytological brush versus regularly used brush in pancreaticobiliary malignancy. Scand J Gastroenterol. 2016. 51(5): 590-3.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"biliary stricture, brush cytology, negative pressure suction, ERCP","lastPublishedDoi":"10.21203/rs.3.rs-5395962/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5395962/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e: To evaluate the effectiveness of negative pressure suction in improving the diagnostic yield of brush cytology for biliary strictures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e: We conducted a prospective study on 48 patients undergoing ERCP. Participants were divided into two groups: those undergoing standard brush cytology (CP group) and those with additional negative pressure suction (NP group). The diagnostic yield of brush cytology and liquid-based cytology were compared, with an emphasis on assessing the independent predictive value of negative pressure and CA125.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e: The application of negative pressure significantly improved the positive diagnosis rate of liquid-based cytology to 75%, compared to standard brush cytology. No significant correlations were found with the length of the biliary stricture. Multivariate analysis revealed negative pressure (OR: 5.4; 95% CI: 1.18–29; p = 0.034) and CA125 (OR: 4.80; 95% CI: 1.07–25.27; p = 0.047) as independent predictors. The predictive model achieved an AUC of 0.823, suggesting a substantial enhancement in diagnostic accuracy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e: Negative pressure suction in brush cytology presents as a superior technique for the diagnosis of biliary strictures, offering a safer and more efficacious alternative to invasive biopsy methods.\u003c/p\u003e","manuscriptTitle":"Negative Pressure Suction in ERCP Brush Cytology: Assessing its Impact on Biliary Stricture Diagnostics","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-10 15:54:30","doi":"10.21203/rs.3.rs-5395962/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2fc4dc28-f537-4f21-a32e-62ff5db4701b","owner":[],"postedDate":"December 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-12-26T21:23:11+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-10 15:54:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5395962","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5395962","identity":"rs-5395962","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}