RT Journal Article SR Electronic T1 The Evaluation of MSX2 mRNA Expression Level in Biliary Brush Cytological Specimens JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 1011 OP 1017 VO 31 IS 3 A1 HIROMICHI ITO A1 KENNICHI SATOH A1 SHIN HAMADA A1 MORIHISA HIROTA A1 ATSUSHI KANNO A1 KAZUYUKI ISHIDA A1 JUN UNNO A1 ATSUSHI MASAMUNE A1 YU KATAYOSE A1 MICHIAKI UNNO A1 TOORU SHIMOSEGAWA YR 2011 UL http://ar.iiarjournals.org/content/31/3/1011.abstract AB Background: To distinguish cholangiocarcinoma from inflammatory disease remains difficult when stricture is present in the bile duct. Endoscopic brushing cytology is a convenient method for stricture in the bile duct, however, the diagnostic sensitivity of this method for malignancy is reported to be low (<60%). Msh homeobox 2 is frequently expressed in carcinoma cells of epithelial origin but not in normal tissues. Aim: To assess whether MSX2 expression level in brushing samples allows differentiation of malignant from benign bile duct stricture. Patients and Methods: Cytological brushing specimens were obtained from strictures of the bile duct during endoscopic retrograde cholangiopancreaticography (ERCP) in 71 patients. The brushing fluid was subjected to cytological diagnosis and RNA extraction. The expression level of MSX2 was evaluated by one-step real-time RT-PCR. Results: MSX2 expression levels were significantly higher in malignant than in benign bile duct stricture (p=0.004). The sensitivity and specificity for cholangiocarcinoma of cytology and MSX2 expression in strictures of the bile duct were: 55.3% and 100%, and 72.3% and 58.3%, respectively. Conclusion: The sensitivity of MSX2 expression level for cholangiocarcinoma was much higher than that of cytology. This suggests that the evaluation of MSX2 level in ERCP brushing samples would be a useful tool to distinguish malignant from benign bile duct stricture.