CT evaluation of locoregional spread of carcinoma of the gallbladder

This study aims to assess the diagnostic capability of CT to preoperatively detect evidence of locoregional spread of gallbladder cancer. Two radiologists independently performed retrospective review of CT scans on 20 patients who had undergone surgical resection for carcinoma of the gallbladder. Local spread was categorized by the TNM system and the results were correlated with surgical and pathologic findings. All cases of hepatic spread (14 cases), common bile duct extension (four cases), pancreatic spread (three cases) and duodenal spread (three cases) were correctly diagnosed by helical CT. One of three cases of peritoneal spread and two of three cases of gastric spread were misdiagnosed. CT evaluation of T stage (T1: one case [5%]; T2: four cases [20%]; T3: four cases [20%], and T4: 11 cases [55%]) was accurate in 85%. The sensitivity and positive predictive value (PPV) of T1-T2 lesions were 80%. The specificity and negative predictive value (NPV) were 93%. For T4 lesions sensitivity, specificity, PPV and NPV were 100%. Helical CT provided 85% accuracy in the diagnosis of the locoregional extent of gallbladder cancer. It allows an acceptable classification according to the TNM staging system and predicts prognosis.