Outcomes after Resection of Intrahepatic Cholangiocarcinoma: External Validation and Comparison of Prognostic Models

BACKGROUND: Published prognostic models for overall survival after liver resection for intrahepatic cholangiocarcinoma require external validation before use in clinical practice. STUDY DESIGN: From January 1993 to May 2013, consecutive patients who underwent resection of intrahepatic cholangiocarcinoma were identified from a prospective database. The Wang nomogram was derived in an Asian cohort (n = 367) and included clinicopathologic variables and preoperative CEA and cancer antigen 19-9 levels. The Hyder nomogram was derived in an Eastern and Western multicenter cohort (n = 514) using clinicopathologic variables only. The AJCC Cancer Staging System (7th ed) and the preoperative Fudan risk score were also evaluated. Prognostic performance was assessed in terms of discrimination, calibration, and stratification. RESULTS: One hundred and eighty-eight patients were included, with a median follow-up of 41 months. Median overall survival was 48.7 months and estimated 3-year and 5-year overall survival rates were 59% and 45%, respectively. Overall survival prediction accuracy, according to concordance-index calculation, was 0.72 with the Wang nomogram, 0.66 with the Hyder nomogram, 0.63 with the AJCC system, and 0.55 using the Fudan score. Both nomograms provided effective patient stratification in distinct survival groups. CONCLUSIONS: Both the Wang and Hyder nomograms provided accurate patient prognosis estimation after liver resection for intrahepatic cholangiocarcinoma and can be useful for decision making about adjuvant therapy. The Wang nomogram appears to be more appropriate in patients undergoing formal portal lymphadenectomy and requires preoperative CEA and cancer antigen 19-9 levels for optimal performance.