The aim of this review is to provide a comprehensive analysis of the existing literature pertaining to cytology of extrahepatic bile ducts. A search using the keywords "biliary brush cytology" was conducted in the PubMed database, with a focus on recent articles. The inclusion criteria primarily encompassed publications addressing problematic biliary stenosis. Emphasis was placed on identifying articles that explored innovative or less-utilized examination techniques aimed at enhancing the sensitivity of cytological examination. This review presents a comprehensive overview of the various types of materials used in sampling and the corresponding sampling methods. Additionally, it explores cytological and cytogenetic techniques, such as fluorescence in situ hybridization (FISH) and genetic methods (miRNA, NGS, cfDNA). These techniques possess the potential to improve the accuracy of diagnosing bile duct tumors, although their sensitivity varies. Furthermore, their utilization can facilitate early therapy, which plays a crucial role in patient prognosis. Each examination is always dependent on the quality and quantity of material delivered. A higher sensitivity of these examinations can be achieved by combining biliary cytology and other complementary methods.

2nd Department of Internal Medicine Gastroenterology and Geriatrics University Hospital Olomouc and Faculty of Medicine and Dentistry Palacky University Olomouc 779 00 Olomouc Czech Republic

Department of Clinical and Molecular Pathology University Hospital Olomouc and Faculty of Medicine and Dentistry Palacky University Olomouc 779 00 Olomouc Czech Republic

Zobrazit více v PubMed

Zdravotnická ročenka České republiky 2019. Zdravotnická statistika ČR. Ústav zdravotnických informací a statistiky ČR. [cited 2023 May 23] Available from: https://www.uzis.cz/res/f/008381/zdrroccz2019.pdf (In Czech)

Zdravotnická ročenka České republiky 2018. Zdravotnická statistika ČR. Ústav zdravotnických informací a statistiky ČR. [cited 2023 May 23] Available from: https://www.uzis.cz/res/f/008280/zdrroccz2018.pdf (In Czech)

Zdravotnická ročenka České republiky 2017. Zdravotnická statistika ČR. Ústav zdravotnických informací a statistiky ČR. [cited 2023 May 23] Available from: https://www.uzis.cz/sites/default/files/knihovna/zdrroccz_2017.pdf (In Czech)

Zdravotnická ročenka České republiky 2016. Zdravotnická statistika ČR. Ústav zdravotnických informací a statistiky ČR. [cited 2023 May 23] Available from: https://www.uzis.cz/sites/default/files/knihovna/zdrroccz2016.pdf (In Czech)

Shaib Y, El-Serag HB. The epidemiology of cholangiocarcinoma. Semin Liver Dis 2004;24(2):115-25. DOI

Banales JM, Marin JJG, Lamarca A, Rodrigues PM, Khan SA, Roberts LR, Cardinale V, Carpino G, Andersen JB, Braconi C, Calvisi DF, Perugorria MJ, Fabris L, Boulter L, Macias RIR, Gaudio E, Alvaro D, Gradilone SA, Strazzabosco M, Marzioni M, Coulouarn C, Fouassier L, Raggi C, Invernizzi P, Mertens JC, Moncsek A, Rizvi S, Heimbach J, Koerkamp BG, Bruix J, Forner A, Bridgewater J, Valle JW, Gores GJ. Cholangiocarcinoma 2020: the next horizon in mechanisms and management. Nat Rev Gastroenterol Hepatol 2020;17(9):557-88. DOI

Rizvi S, Gores GJ. Pathogenesis, diagnosis, and management of cholangiocarcinoma. Gastroenterology 2013;145(6):1215-29. DOI

Tyson GL, El-Serag HB. Risk factors for cholangiocarcinoma. Hepatology 2011;54(1):173-84. DOI

Saif MW. Pancreatic neoplasm in 2011: an update. JOP 2011;12:316-21.

WHO Classification of Tumours Editorial Board. Digestive system tumours. Lyon (France): International Agency for Research on Cancer; 2019. (WHO classification of tumours series, 5th ed.; vol. 1).

Martinez NS, Trindade AJ, Sejpal DV. Determining the Indeterminate Biliary Stricture: Cholangioscopy and Beyond. Curr Gastroenterol Rep 2020;22(12):58. DOI

Ghisa M, Bellumat A, De Bona M, Valiante F, Tollardo M, Riguccio G, Iacobellis A, Savarino E, Buda A. Biliary Tree Diagnostics: Advances in Endoscopic Imaging and Tissue Sampling. Medicina 2022;58(1):135. DOI

Geier A, Gartung C, Dietrich CG, Lammert F, Wasmuth HE, Matern S. Diagnostik cholestatischer Erkrankungen [Diagnosis of cholestatic disorders]. Med Klin (Munich). 2003;98(9):499-509. (In German). DOI

Pitman MB, Centeno BA, Ali SZ, Genevay M, Stelow E, Mino-Kenudson M, Fernandez-del Castillo C, Max Schmidt C, Brugge W, Layfield L; Papanicolaou Society of Cytopathology. Standardized terminology and nomenclature for pancreatobiliary cytology: the Papanicolaou Society of Cytopathology guidelines. Diagn Cytopathol 2014;42(4):338-50. DOI

Pitman MB, Layfield LJ. The Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology. Berlin/Heidelberg, Germany: Springer; 2015. DOI

Friman S. Cholangiocarcinoma-current treatment options. Scand J Surg 2011;100:30-4. DOI

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. DOI

Ding SM, Lu AL, Xu BQ, Shi SH, Edoo MIA, Zheng SS, Li QY. Accuracy of brush cytology in biliopancreatic strictures: a single-center cohort study. J Int Med Res 2021;49(2):300060520987771. DOI

Tamada K, Ushio J, Sugano K. Endoscopic diagnosis of extrahepatic bile duct carcinoma: Advances and current limitations. World J Clin Oncol 2011;2(5):203-16. DOI

Ponchon T, Gagnon P, Berger F, Labadie M, Liaras A, Chavaillon A, Bory R. Value of endobiliary brush cytology and biopsies for the diagnosis of malignant bile duct stenosis: results of a prospective study. Gastrointest Endosc 1995;42(6):565-72. DOI

Gupta M, Radha RP, Devi D, Sandeep G, Suresh S. Role of biliary tract cytology in the evaluation of extrahepatic cholestatic jaundice. J Cytol 2013;30(3):162-8. DOI

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. DOI

Abbasi MR, Ghazi Mirsaeed SM, Mohammad Alizadeh AH. Diagnosis of Malignant Biliary Strictures: Conventional or Negative Pressure Brush Cytology? Asian Pac J Cancer Prev 2016;17(10):4563-66.

Archibugi L, Mariani A, Ciambriello B, Petrone MC, Rossi G, Testoni SGG, Carlucci M, Aldrighetti L, Falconi M, Balzano G, Doglioni C, Capurso G, Arcidiacono PG. High sensitivity of ROSE-supported ERCP-guided brushing for biliary strictures. Endosc Int Open 2021;9(3):E363-E370. DOI

Sugimoto S, Matsubayashi H, Kimura H, Sasaki K, Nagata K, Ohno S, Uesaka K, Mori K, Imai K, Hotta K, Takizawa K, Kakushima N, Tanaka M, Kawata N, Ono H. Diagnosis of bile duct cancer by bile cytology: usefulness of post-brushing biliary lavage fluid. Endosc Int Open 2015;3(4):E323-8. DOI

Motomura Y, Akahoshi K, Kajiyama K, Gibo J, Miyamoto K, Ikeda H, Yamaguchi E, Teramatsu K, Utsunomiya R, Miyagaki A, Ooya M, Ihara E. Utility of lavage cytology plus targeted biopsy during cholangioscopy for the diagnosis of indeterminate biliary lesions. Gastroenterol Hepatol Endosc 2017;2(3):1-4. DOI

Bank JS, Witt BL, Taylor LJ, Adler DG. Diagnostic yield and accuracy of a new cytology brush design compared to standard brush cytology for evaluation of biliary strictures. Diagn Cytopathol 2018;46(3):234-8. DOI

Tamada K, Tomiyama T, Wada S, Ohashi A, Satoh Y, Ido K, Sugano K. Endoscopic transpapillary bile duct biopsy with the combination of intraductal ultrasonography in the diagnosis of biliary strictures. Gut 2002;50(3):326-31. DOI

Sugiyama M, Atomi Y, Wada N, Kuroda A, Muto T. Endoscopic transpapillary bile duct biopsy without sphincterotomy for diagnosing biliary strictures: a prospective comparative study with bile and brush cytology. Am J Gastroenterol 1996;91(3):465-7.

Howell DA, Parsons WG, Jones MA, Bosco JJ, Hanson BL. Complete tissue sampling of biliary strictures at ERCP using a new device. Gastrointest Endosc 1996;43(5):498-502. DOI

Fukuda Y, Tsuyuguchi T, Sakai Y, Tsuchiya S, Saisyo H. Diagnostic utility of peroral cholangioscopy for various bile-duct lesions. Gastrointest Endosc 2005;62(3):374-82. DOI

Nishikawa T, Tsuyuguchi T, Sakai Y, Sugiyama H, Miyazaki M, Yokosuka O. Comparison of the diagnostic accuracy of peroral video-cholangioscopic visual findings and cholangioscopy-guided forceps biopsy findings for indeterminate biliary lesions: a prospective study. Gastrointest Endosc 2013;77(2):219-26. DOI

Osanai M, Itoi T, Igarashi Y, Tanaka K, Kida M, Maguchi H, Yasuda K, Okano N, Imaizumi H, Itokawa F. Peroral video cholangioscopy to evaluate indeterminate bile duct lesions and preoperative mucosal cancerous extension: a prospective multicenter study. Endoscopy 2013;45(8):635-42. DOI

Chen YK, Pleskow DK. SpyGlass single-operator peroral cholangiopancreatoscopy system for the diagnosis and therapy of bile-duct disorders: a clinical feasibility study (with video). Gastrointest Endosc 2007;65(6):832-41. DOI

Urban O, Evinová E, Fojtík P, Loveček M, Kliment M, Zoundjiekpon V, Falt P. Digital cholangioscopy: the diagnostic yield and impact on management of patients with biliary stricture. Scand J Gastroenterol 2018;53(10-11):1364-7. DOI

Garrow D, Miller S, Sinha D, Conway J, Hoffman BJ, Hawes RH, Romagnuolo J. Endoscopic ultrasound: a meta-analysis of test performance in suspected biliary obstruction. Clin Gastroenterol Hepatol 2007;5(5):616-23. DOI

DeWitt J, Misra VL, Leblanc JK, McHenry L, Sherman S. EUS-guided FNA of proximal biliary strictures after negative ERCP brush cytology results. Gastrointest Endosc 2006;64(3):325-33. DOI

Bergquist A, Tribukait B, Glaumann H, Broomé U. Can DNA cytometry be used for evaluation of malignancy and premalignancy in bile duct strictures in primary sclerosing cholangitis? J Hepatol 2000;33(6):873-7. DOI

Moreno Luna LE, Kipp B, Halling KC, Sebo TJ, Kremers WK, Roberts LR, Barr Fritcher EG, Levy MJ, Gores GJ. Advanced cytologic techniques for the detection of malignant pancreatobiliary strictures. Gastroenterology 2006;131(4):1064-72. DOI

Barr Fritcher EG, Voss JS, Jenkins SM, Lingineni RK, Clayton AC, Roberts LR, Halling KC, Talwalkar JA, Gores GJ, Kipp BR. Primary sclerosing cholangitis with equivocal cytology: fluorescence in situ hybridization and serum CA 19-9 predict risk of malignancy. Cancer Cytopathol 2013;121(12):708-17. DOI

Barr Fritcher EG, Kipp BR, Voss JS, Clayton AC, Lindor KD, Halling KC, Gores GJ. Primary sclerosing cholangitis patients with serial polysomy fluorescence in situ hybridization results are at increased risk of cholangiocarcinoma. Am J Gastroenterol 2011;106(11):2023-8. DOI

Timmer MR, Lau CT, Meijer SL, Fockens P, Rauws EA, Ponsioen CY, Calpe S, Krishnadath KK. Genetic Abnormalities in Biliary Brush Samples for Distinguishing Cholangiocarcinoma from Benign Strictures in Primary Sclerosing Cholangitis. Gastroenterol Res Pract 2016;2016:4381513. DOI

Liggett WH Jr, Sidransky D. Role of the p16 tumor suppressor gene in cancer. J Clin Oncol 1998;16(3):1197-206. DOI

Gonda TA, Glick MP, Sethi A, Poneros JM, Palmas W, Iqbal S, Gonzalez S, Nandula SV, Emond JC, Brown RS, Murty VV, Stevens PD. Polysomy and p16 deletion by fluorescence in situ hybridization in the diagnosis of indeterminate biliary strictures. Gastrointest Endosc 2012;75(1):74-9. DOI

Bubendorf L, Piaton E. UroVysion® multiprobe FISH in the triage of equivocal urinary cytology cases. Ann Pathol 2012;32(6):e52-6, 438-43. DOI

Fernández MI, Parikh S, Grossman HB, Katz R, Matin SF, Dinney CP, Kamat AM. The role of FISH and cytology in upper urinary tract surveillance after radical cystectomy for bladder cancer. Urol Oncol 2012;30(6):821-4. DOI

Gomella LG, Mann MJ, Cleary RC, Hubosky SG, Bagley DH, Thumar AB, McCue PA, Lallas CD, Trabulsi EJ. Fluorescence in situ hybridization (FISH) in the diagnosis of bladder and upper tract urothelial carcinoma: the largest single-institution experience to date. Can J Urol 2017;24(1):8620-6.

Halling KC, King W, Sokolova IA, Meyer RG, Burkhardt HM, Halling AC, Cheville JC, Sebo TJ, Ramakumar S, Stewart CS, Pankratz S, O'Kane DJ, Seelig SA, Lieber MM, Jenkins RB. A comparison of cytology and fluorescence in situ hybridization for the detection of urothelial carcinoma. J Urol 2000;164(5):1768-75. DOI

Vlajnic T, Somaini G, Savic S, Barascud A, Grilli B, Herzog M, Obermann EC, Holmes BJ, Ali SZ, Degen L, Bubendorf L. Targeted multiprobe fluorescence in situ hybridization analysis for elucidation of inconclusive pancreatobiliary cytology. Cancer Cytopathol 2014;122(8):627-34. DOI

Chaiteerakij R, Barr Fritcher EG, Angsuwatcharakon P, Ridtitid W, Chaithongrat S, Leerapun A, Baron TH, Kipp BR, Henry MR, Halling KC, Rerknimitr R, Roberts LR. Fluorescence in situ hybridization compared with conventional cytology for the diagnosis of malignant biliary tract strictures in Asian patients. Gastrointest Endosc 2016;83(6):1228-35. DOI

Clayton AC, Zhang J, Roberts LR, Gores GJ, Halling KC, Kipp BR. An Optimized Set of Fluorescence In Situ Hybridization Probes for Detection of Pancreatobiliary Tract Cancer in Cytology Brush Samples. Gastroenterology 2015;149(7):1813-24. DOI

Zoundjiekpon VD, Falt P, Zapletalova J, Vanek P, Kurfurstova D, Slobodova Z, Skanderova D, Korinkova G, Skalicky P, Lovecek M, Urban O. Fluorescence In Situ Hybridization in Primary Diagnosis of Biliary Strictures: A Single-Center Prospective Interventional Study. Biomedicines 2023;11(3):755. DOI

Zheng Y, Qin Y, Gong W, Li H, Li B, Wang Y, Chao B, Zhao S, Liu L, Yao S, Shi J, Shi X, Wang K, Xu S. Specific genomic alterations and prognostic analysis of perihilar cholangiocarcinoma and distal cholangiocarcinoma. J Gastrointest Oncol 2021;12(6):2631-42. DOI

Harbhajanka A, Michael CW, Janaki N, Gokozan HN, Wasman J, Bomeisl P, Yoest J, Sadri N. Tiny but mighty: use of next generation sequencing on discarded cytocentrifuged bile duct brushing specimens to increase sensitivity of cytological diagnosis. Mod Pathol 2020;33(10):2019-25. DOI

Bailey P, Chang DK, Nones K, Johns AL, Patch AM, Gingras MC, Miller DK, Christ AN, Bruxner TJ, Quinn MC, Nourse C, Murtaugh LC, Harliwong I, Idrisoglu S, Manning S, Nourbakhsh E, Wani S, Fink L, Holmes O, Chin V, Anderson MJ, Kazakoff S, Leonard C, Newell F, Waddell N, Wood S, Xu Q, Wilson PJ, Cloonan N, Kassahn KS, Taylor D, Quek K, Robertson A, Pantano L, Mincarelli L, Sanchez LN, Evers L, Wu J, Pinese M, Cowley MJ, Jones MD, Colvin EK, Nagrial AM, Humphrey ES, Chantrill LA, Mawson A, Humphris J, Chou A, Pajic M, Scarlett CJ, Pinho AV, Giry-Laterriere M, Rooman I, Samra JS, Kench JG, Lovell JA, Merrett ND, Toon CW, Epari K, Nguyen NQ, Barbour A, Zeps N, Moran-Jones K, Jamieson NB, Graham JS, Duthie F, Oien K, Hair J, Grützmann R, Maitra A, Iacobuzio-Donahue CA, Wolfgang CL, Morgan RA, Lawlor RT, Corbo V, Bassi C, Rusev B, Capelli P, Salvia R, Tortora G, Mukhopadhyay D, Petersen GM; Australian Pancreatic Cancer Genome Initiative; Munzy DM, Fisher WE, Karim SA, Eshleman JR, Hruban RH, Pilarsky C, Morton JP, Sansom OJ, Scarpa A, Musgrove EA, Bailey UM, Hofmann O, Sutherland RL, Wheeler DA, Gill AJ, Gibbs RA, Pearson JV, Waddell N, Biankin AV, Grimmond SM. Genomic analyses identify molecular subtypes of pancreatic cancer. Nature 2016;531(7592):47-52. DOI

Witkiewicz AK, McMillan EA, Balaji U, Baek G, Lin WC, Mansour J, Mollaee M, Wagner KU, Koduru P, Yopp A, Choti MA, Yeo CJ, McCue P, White MA, Knudsen ES. Whole-exome sequencing of pancreatic cancer defines genetic diversity and therapeutic targets. Nat Commun 2015;6:6744. DOI

Biankin AV, Waddell N, Kassahn KS, Gingras MC, Muthuswamy LB, Johns AL, Miller DK, Wilson PJ, Patch AM, Wu J, Chang DK, Cowley MJ, Gardiner BB, Song S, Harliwong I, Idrisoglu S, Nourse C, Nourbakhsh E, Manning S, Wani S, Gongora M, Pajic M, Scarlett CJ, Gill AJ, Pinho AV, Rooman I, Anderson M, Holmes O, Leonard C, Taylor D, Wood S, Xu Q, Nones K, Fink JL, Christ A, Bruxner T, Cloonan N, Kolle G, Newell F, Pinese M, Mead RS, Humphris JL, Kaplan W, Jones MD, Colvin EK, Nagrial AM, Humphrey ES, Chou A, Chin VT, Chantrill LA, Mawson A, Samra JS, Kench JG, Lovell JA, Daly RJ, Merrett ND, Toon C, Epari K, Nguyen NQ, Barbour A, Zeps N; Australian Pancreatic Cancer Genome Initiative; Kakkar N, Zhao F, Wu YQ, Wang M, Muzny DM, Fisher WE, Brunicardi FC, Hodges SE, Reid JG, Drummond J, Chang K, Han Y, Lewis LR, Dinh H, Buhay CJ, Beck T, Timms L, Sam M, Begley K, Brown A, Pai D, Panchal A, Buchner N, De Borja R, Denroche RE, Yung CK, Serra S, Onetto N, Mukhopadhyay D, Tsao MS, Shaw PA, Petersen GM, Gallinger S, Hruban RH, Maitra A, Iacobuzio-Donahue CA, Schulick RD, Wolfgang CL, Morgan RA, Lawlor RT, Capelli P, Corbo V, Scardoni M, Tortora G, Tempero MA, Mann KM, Jenkins NA, Perez-Mancera PA, Adams DJ, Largaespada DA, Wessels LF, Rust AG, Stein LD, Tuveson DA, Copeland NG, Musgrove EA, Scarpa A, Eshleman JR, Hudson TJ, Sutherland RL, Wheeler DA, Pearson JV, McPherson JD, Gibbs RA, Grimmond SM. Pancreatic cancer genomes reveal aberrations in axon guidance pathway genes. Nature 2012;491(7424):399-405. DOI

Javle M, Bekaii-Saab T, Jain A, Wang Y, Kelley RK, Wang K, Kang HC, Catenacci D, Ali S, Krishnan S, Ahn D, Bocobo AG, Zuo M, Kaseb A, Miller V, Stephens PJ, Meric-Bernstam F, Shroff R, Ross J. Biliary cancer: Utility of next-generation sequencing for clinical management. Cancer 2016;122(24):3838-47. DOI

DiPeri TP, Javle MM, Meric-Bernstam F. Next generation sequencing for biliary tract cancers. Expert Rev Gastroenterol Hepatol 2021;15(5):471-4. DOI

Gonda TA, Viterbo D, Gausman V, Kipp C, Sethi A, Poneros JM, Gress F, Park T, Khan A, Jackson SA, Blauvelt M, Toney N, Finkelstein SD. Mutation Profile and Fluorescence In Situ Hybridization Analyses Increase Detection of Malignancies in Biliary Strictures. Clin Gastroenterol Hepatol 2017;15(6):913-919.e1. DOI

Dudley JC, Zheng Z, McDonald T, Le LP, Dias-Santagata D, Borger D, Batten J, Vernovsky K, Sweeney B, Arpin RN, Brugge WR, Forcione DG, Pitman MB, Iafrate AJ. Next-Generation Sequencing and Fluorescence in Situ Hybridization Have Comparable Performance Characteristics in the Analysis of Pancreaticobiliary Brushings for Malignancy. J Mol Diagn 2016;18(1):124-30. DOI

Jusakul A, Cutcutache I, Yong CH, Lim JQ, Huang MN, Padmanabhan N, Nellore V, Kongpetch S, Ng AWT, Ng LM, Choo SP, Myint SS, Thanan R, Nagarajan S, Lim WK, Ng CCY, Boot A, Liu M, Ong CK, Rajasegaran V, Lie S, Lim AST, Lim TH, Tan J, Loh JL, McPherson JR, Khuntikeo N, Bhudhisawasdi V, Yongvanit P, Wongkham S, Totoki Y, Nakamura H, Arai Y, Yamasaki S, Chow PK, Chung AYF, Ooi LLPJ, Lim KH, Dima S, Duda DG, Popescu I, Broet P, Hsieh SY, Yu MC, Scarpa A, Lai J, Luo DX, Carvalho AL, Vettore AL, Rhee H, Park YN, Alexandrov LB, Gordân R, Rozen SG, Shibata T, Pairojkul C, Teh BT, Tan P. Whole-Genome and Epigenomic Landscapes of Etiologically Distinct Subtypes of Cholangiocarcinoma. Cancer Discov 2017;7(10):1116-35. DOI

Gupta A, Kurzrock R, Adashek JJ. Evolution of the Targeted Therapy Landscape for Cholangiocarcinoma: Is Cholangiocarcinoma the 'NSCLC' of GI Oncology? Cancers (Basel) 2023;15(5):1578. DOI

FDA grants accelerated approval to pemigatinib for cholangiocarcinoma with an FGFR2 rearrangement or fusion. [cited 2023 May 23] Available from: https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-pemigatinib-cholangiocarcinoma-fgfr2-rearrangement-or-fusion

FDA grants accelerated approval to futibatinib for cholangiocarcinoma. [cited 2023 May 23] Available form: https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-futibatinib-cholangiocarcinoma

Lee RC, Feinbaum RL, Ambros V. The C. elegans heterochronic gene lin-4 encodes small RNAs with antisense complementarity to lin-14. Cell 1993;75(5):843-54. DOI

Li L, Masica D, Ishida M, Tomuleasa C, Umegaki S, Kalloo AN, Georgiades C, Singh VK, Khashab M, Amateau S, Li Z, Okolo P, Lennon AM, Saxena P, Geschwind JF, Schlachter T, Hong K, Pawlik TM, Canto M, Law J, Sharaiha R, Weiss CR, Thuluvath P, Goggins M, Shin EJ, Peng H, Kumbhari V, Hutfless S, Zhou L, Mezey E, Meltzer SJ, Karchin R, Selaru FM. Human bile contains microRNA-laden extracellular vesicles that can be used for cholangiocarcinoma diagnosis. Hepatology 2014;60(3):896-907. DOI

Chapman MH, Tidswell R, Dooley JS, Sandanayake NS, Cerec V, Deheragoda M, Lee AJ, Swanton C, Andreola F, Pereira SP. Whole genome RNA expression profiling of endoscopic biliary brushings provides data suitable for biomarker discovery in cholangiocarcinoma. J Hepatol 2012;56(4):877-85. DOI

Shigehara K, Yokomuro S, Ishibashi O, Mizuguchi Y, Arima Y, Kawahigashi Y, Kanda T, Akagi I, Tajiri T, Yoshida H, Takizawa T, Uchida E. Real-time PCR-based analysis of the human bile microRNAome identifies miR-9 as a potential diagnostic biomarker for biliary tract cancer. PLoS One 2011;6(8):e23584. DOI

Gao L, He SB, Li DC. Effects of miR-16 plus CA19-9 detections on pancreatic cancer diagnostic performance. Clin Lab 2014;60(1):73-7. DOI

Kim K, Yoo D, Lee HS, Lee KJ, Park SB, Kim C, Jo JH, Jung DE, Song SY. Identification of potential biomarkers for diagnosis of pancreatic and biliary tract cancers by sequencing of serum microRNAs. BMC Med Genomics 2019;12(1):62. DOI

Jamieson NB, Morran DC, Morton JP, Ali A, Dickson EJ, Carter CR, Sansom OJ, Evans TR, McKay CJ, Oien KA. MicroRNA molecular profiles associated with diagnosis, clinicopathologic criteria, and overall survival in patients with resectable pancreatic ductal adenocarcinoma. Clin Cancer Res 2012;18(2):534-45. DOI

Le N, Fillinger J, Szanyi S, Wichmann B, Nagy ZB, Ivády G, Burai M, Tarpay Á, Pozsár J, Pap Á, Molnár B, Csuka O, Bak M, Tulassay Z, Szmola R. Analysis of microRNA expression in brush cytology specimens improves the diagnosis of pancreatobiliary cancer. Pancreatology 2019;19(6):873-9. DOI

Ueta E, Tsutsumi K, Kato H, Matsushita H, Shiraha H, Fujii M, Matsumoto K, Horiguchi S, Okada H. Extracellular vesicle-shuttled miRNAs as a diagnostic and prognostic biomarker and their potential roles in gallbladder cancer patients. Sci Rep 202;11(1):12298. DOI

Keane MG, Huggett MT, Chapman MH, Johnson GJ, Webster GJ, Thorburn D, Mackay J, Pereira SP. Diagnosis of pancreaticobiliary malignancy by detection of minichromosome maintenance protein 5 in biliary brush cytology. Br J Cancer 2017;116(3):349-55. DOI

Prachayakul V, Rugivarodom M, Nopjaroonsri P, Cheirsilpa K, Chang A, Kamolhan T, Boonyaarunnate T, Thuwajit C, Thuwajit P. Diagnostic power of DNA methylation markers suggestive of cholangiocarcinoma in ERCP-based brush cytology. Gastrointest Endosc 2022;95(1):123-130.e1. DOI

Lamarca A, Kapacee Z, Breeze M, Bell C, Belcher D, Staiger H, Taylor C, McNamara MG, Hubner RA, Valle JW. Molecular Profiling in Daily Clinical Practice: Practicalities in Advanced Cholangiocarcinoma and Other Biliary Tract Cancers. J Clin Med 2020;9(9):2854. DOI

Maron SB, Chase LM, Lomnicki S, Kochanny S, Moore KL, Joshi SS, Landron S, Johnson J, Kiedrowski LA, Nagy RJ, Lanman RB, Kim ST, Lee J, Catenacci DVT. Circulating Tumor DNA Sequencing Analysis of Gastroesophageal Adenocarcinoma. Clin Cancer Res 2019;25(23):7098-112. DOI

Berchuck JE, Facchinetti F, DiToro DF, Baiev I, Majeed U, Reyes S, Chen C, Zhang K, Sharman R, Uson Junior PLS, Maurer J, Shroff RT, Pritchard CC, Wu MJ, Catenacci DVT, Javle M, Friboulet L, Hollebecque A, Bardeesy N, Zhu AX, Lennerz JK, Tan B, Borad M, Parikh AR, Kiedrowski LA, Kelley RK, Mody K, Juric D, Goyal L. The clinical landscape of cell-free DNA alterations in 1671 patients with advanced biliary tract cancer. Ann Oncol 2022;33(12):1269-83. DOI

Lapitz A, Azkargorta M, Milkiewicz P, Olaizola P, Zhuravleva E, Grimsrud MM, Schramm C, Arbelaiz A, O'Rourke CJ, La Casta A, Milkiewicz M, Pastor T, Vesterhus M, Jimenez-Agüero R, Dill MT, Lamarca A, Valle JW, Macias RIR, Izquierdo-Sanchez L, Castaño YP, Caballero-Camino FJ, Riaño I, Krawczyk M, Ibarra C, Bustamante J, Nova-Camacho LM, Falcon-Perez JM, Elortza F, Perugorria MJ, Andersen JB, Bujanda L, Karlsen TH, Folseraas T, Rodrigues PM, Banales JM. Liquid biopsy-based protein biomarkers for risk prediction, early diagnosis and prognostication of cholangiocarcinoma. J Hepatol 2023:S0168-8278(23)00159-9. DOI