Comparison of the Sixth and the Seventh Editions of the UICC Classification for Perihilar Cholangiocarcinoma

Abstract

BACKGROUND: The seventh edition of the TNM classification separates extrahepatic bile duct tumors into perihilar and distal tumors and further changes the definition of the TNM classification. The impact of the seventh edition on stage-based prognostic prediction for patients with perihilar cholangiocarcinoma was evaluated. METHODS: Between January 1998 and March 2010, 223 consecutive patients with perihilar cholangiocarcinoma underwent surgery at the West German Cancer Center. Median survival times were calculated for the 195 evaluable patients (excluding those with in-hospital mortality) after separate classification by both sixth and seventh editions. RESULTS: Median overall survival was increased in patients classified using the seventh compared with the sixth edition (UICC I: 56.5 vs 23.75 months; II: 45.9 vs 31.6 months; III: 21.3 vs. 8.76 months; IV: 7.03 vs 5.93 months). The T category of the seventh edition did not alter median survival times of T1 (54.07 months) and T4 (7.83 months) cases, but median survival was prolonged for T2 patients (29.4 vs 31.6 months), and shortened for T3 patients (19.43 vs 11.8 months) staged using the seventh edition. According to Cox proportional hazards regression analysis, patient survival was better predicted by the seventh edition UICC stage and pT categories (p=0.0014 and p=0.0396, respectively), than the corresponding sixth edition categories (p=0.4376 and p=0.0926, respectively). CONCLUSIONS: The UICC seventh edition TNM classification for perihilar cholangiocarcinoma improves separation of patients with intermediate stage tumors compared with the sixth edition. The prognostic value of the UICC staging system has been strengthened by the introduction of the seventh edition.