Intrahepatic, peri-hilar and distal cholangiocarcinoma: Three different locations of the same tumor or three different tumors?

BACKGROUND:Few papers deal with pathologic characteristics and outcome of the 3 different cholangiocarcinomas based on location (intrahepatic, peri-hilar, distal). There is little evidence regarding similarity and differences.PATIENTS AND METHODS:From two tertiary referral Italian Centers (in Bologna and Verona), 479 patients with cholangiocarcinoma were evaluated between 1980 and 2011. Several pathologic characteristics and their impact on survival were analyzed among resected patients for cholangiocarcinomas depending on the site of origin.RESULTS:Tumour location was intrahepatic in 172 cases (36%), peri-hilar in 243 (51) and distal in 64(13%). Curative resection was performed in 339 (70%) patients. Intrahepatic cholangiocarcinoma showed higher probability to achieve R0 resection (81%), but was more frequently associated with presence of microvascular invasion (71%). Distal cholangiocarcinoma presented less R0 resections (58%), higher lymphnode involvement (60%) and lower microvascular invasion (49%). Hilar cholangiocarcinoma had intermediate characteristics (R0: 65% of cases). Median follow up was 30.2 ± 38 months; the 5 years overall survival was 31% in the resected population. Overall survival curves were similar among the three groups. At univariate analysis surgical margins, lymphnode status, perineural invasion, T category, TNM stage, microvascular invasion, tumour grading had significant impact on survival. At multivariate analysis, only microvascular invasion was significantly related to long term results (HR = 1,7; 95% CI = 1,0-2,5)".CONCLUSION:Micro-vascular invasion has the strongest impact on survival in all three types of cholangiocarcinoma. In case of comparable pathologic characteristics and stage, the three tumors show similar outcome; depending on location, it shows a different tendency to invade bordering structures which affect the outcome.