Comparison of MRI findings of small hepatocellular carcinoma and small intrahepatic mass-forming cholangiocarcinoma / 中华放射学杂志

ABSTRACT

Objective To compare the MR features of small hepatocellular carcinoma (sHCC) and small intrahepatic mass-forming cholangiocarcinoma (sIMCC) (≤ 3 cm) and improve the accuracy in diagnosis.Methods Imaging studies of 318 patients with 351 sHCCs and 42 patients with 47 sIMCCs were retrospectively reviewed.Signal intensity on T2WI and on each phase of dynamic enhanced imaging,enhancement patterns,and accompanying findings of the two groups were compared by qualitative and quantitative studies.The qualitative imaging features of tumors were compared by the x2 test and the Fisher exact test,and the statistically significant variables obtained from univariate analysis were used to conduct multivariate stepwise logistic regression analysis.Enhancement pattern between sHCCs with elevated AFP and normal AFP were assessed by thex2 test.Results Multivariate analysis indicated that signal features of enhancement pattern and the accompanying findings of tumor capsule and hepatic capsule retraction were key predictors in differentiating sHCC from sIMCCWash-out pattern (276/351) with enhanced tumor capsule (275/351) highly indicated sHCC,while progressive enhancement pattern (27/47) with hepatic capsule retraction (8/47) indicated the diagnosis of sIMCC (P ＜ 0.01).Compared with sHCC with normal AFP,atypical patterns as progressive (n =4) and stable enhancement (n =32) were more commonIy seen in lesions with elevated AFP,dynamic enhancement pattern was different between the two subgroups (x2 =8.241,P ＜ 0.05).Conclusions Enhancement patterns and the accompanying tumor capsule and hepatic capsule retraction were the most important predictors in differentiating sHCC from sIMCC.In addition,enhancement pattern was relatively more typical in sHCCs with normal AFP which provided valuable information in diagnosis for clinicians.