Abstract: Objective To investigate factors at initial presentation of hepatocellular carcinoma（HCC） that are associated with the presence of extrahepatic collateral arteries（ExCAs）. Methods A consecutive sample of 121 patients newly diagnosed with HCC based on pathology were prospectively enrolled.Thin-section computed tomography（CT） findings were compared with surgical and pathological findings.Several features were analyzed for their potential relationship with the presence of ExCAs，including tumor size， surface location，pseudocapsule，and histopathological grade of ExCA blood supply to HCC. Results Pathology analysis identified 24 of 121 patients （19.8%） with 28 ExCAs supplying tumors; CT identified 27  patients with 30 ExCAs. CT showed high sensitivity （96.0%），specificity （96.9%） and accuracy （96.7%） for detecting ExCAs.Multiple logistic regression identified tumor size and surface location as significantly associated with the presence of ExCAs（P<0.05），while histopathological grade and the presence of pseudocapsule were not（P>0.05）. Conclusion CT reconstruction techniques can accurately reveal ExCAs in HCC patients. Certain CT findings（tumor size， surface location）are significant predictors of the presence of ExCAs.

Key words: Liver neoplasm, Computed tomography, Extrahepatic collateral artery, Vascular reconstruction technique