Hilar cholangiocarcinoma: tumor depth as a predictor of outcome.

Background: The American Joint Committee on Cancer staging system for hilar cholangiocarcinoma may be inaccurate because the bile duct lacks discrete tissue boundaries.

Objectives: To examine the accuracy of the American Joint Committee on Cancer staging schemes and to determine the prognostic implications of tumor depth.

Design, Setting, And Patients: From January 1, 1987, through December 31, 2009, there were 106 patients who underwent resection of hilar cholangiocarcinoma who had pathologic slides available for re-review.

Main Outcome Measures: Tumor depth and overall survival.

Results: Overall median survival was 19.9 months. The 6th and 7th editions of the T-classification criteria were unable to discriminate among T1, T2, and T3 lesions (P > .05 for all). Median survival was associated with the invasion depth of the tumor (≥5 mm vs <5 mm): 18 months vs 30 months (P = .01). On multivariate analysis, tumor depth remained predictive of disease-specific death (hazard ratio, 1.70; P = .03).

Conclusions: The American Joint Committee on Cancer T-classification criteria did not stratify patients with regard to prognosis. Depth of tumor invasion is a better predictor of long-term outcome.