Increasing evidence has demonstrated that serum soluble B7-H4 (sB7-H4) is a useful tumour marker for cancer diagnosis and prognosis evaluation. Whether sB7-H4 is expressed in the bile of cholangiocarcinoma (CC) and is related to the progression of CC need to be explored. Bile sB7-H4 was obtained through endoscopic retrograde cholangiopancreatography (ERCP) from 213 patients with biliary strictures and detected was detected by a B7-H4 ELISA kit. Diagnostic value was compared among bile sB7-H4, CA19-9, CA12-5, CEA and ERCP-based cytological/tissue examination. Additionally, the correlations between the bile sB7-H4 concentration and the clinical characteristics of early-stage cholangiocarcinoma (ESCC) were studied. The bile sB7-H4 levels of patients with ESCC were significantly higher than in patients with benign biliary strictures (BBS) (P
