Abstract： Objective To explore the risk factors,treatment and outcomes of biloma after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC).Methods A total of 481 patients with a diagnosis of HCC underwent TACE at our hospital from January 2011 to December 2013.Biloma was tracked by the follow-ups of computed tomography or magnetic resonance imaging (CT/MRI).Retrospective analyses were conducted for their clinical features,treatments and prognosis.The statistically significant factors for univariate analysis were introduced into Logistic regression models for multivariate analysis to obtain the risk factors of biloma post-TACE.Results There were 43 cases of complicated biloma after TACE.And 38 patients (88.4％) developed biloma at 0.5-3 months post-TACE while another 5 (9.7％) did so at 3-5 months.The multivariate analysis showed that bile duct dilation,a history of hepatectomy prior to TACE,use of polyvinyl alcohol (PVA) particles and nonsuperselective embolization were the risk factors of biloma formation after TACE.Among 9 symptomatics,there were jaundice (n =2) and fever (n =7).The diameter of bilomas was (8.07 ± 3.53) cm for 9 symptomatics and (2.81 ± 1.26) cm for 35 asymptomatics.And the difference was statistically significant (P ＜0.01).Nine symptomatic patients underwent percutaneous drainage with tube and biloma diminished (n =7) and even vanished (n =2).Only conservative treatment was offered for 35 asymptomatics.During the follow-ups,it showed no change (n =24),diminishing (n =8) and disappearance (n =2).One case died from a greatly enlarged biloma due to hepatic failure and septic shock via a rupture into abdominal cavity and choleperitonitis.Conclusion The risk factors of biloma formation after TACE for HCC are bile duct dilation,a history of hepatectomy before TACE,use of PVA particles and nonsuperselective embolization.For symptomatics,drainage must be performed timely and the prognosis is fair.For asymptomatics,regular imaging follow-ups are needed.Drainage must be performed timely when the diameter of biloma increased significantly during the follow-ups.