A novel online prognostic tool to predict long‐term survival after liver resection for intrahepatic cholangiocarcinoma: The “metro‐ticket” paradigm

Background: The aim of the current study was to develop an online calculator to predict survival after liver resection for intrahepatic cholangiocarcinoma (ICC) based on the “metro-ticket” paradigm. Methods: Between 1990 and 2016, patients who underwent liver resection for ICC were identified in an international multi-institutional database. The final multivariable model of survival was used to develop an online prognostic calculator of survival. Results: Among 643 patients, actual 5-year overall survival (OS) after resection for ICC was 42.7%. On multivariable analysis, CA19-9 > 200 (hazard ratio (HR), 2.62; 95% CI, 2.01-3.42), sum of the number and largest tumor size >7 (HR, 1.88; 95% CI, 1.46-2.42), N1 disease (HR, 2.87; 95% CI, 1.98-4.16), R1 resection (HR, 1.72; 95% CI, 1.21-2.46), poor/undifferentiated tumor grade (HR, 1.74; 95% CI, 1.25-2.44), major vascular invasion (HR, 1.47; 95% CI, 1.03-2.10), and adjuvant chemotherapy (HR, 0.64; 95% CI, 0.45-0.89) were significantly associated with survival and were included in the online calculator. The predictive accuracy of the model was good to very good as the C-statistics to predict 5-year OS was 0.696 in the training dataset and 0.672 with bootstrapping resamples (n = 5000) in the test dataset. Conclusion: A novel, online calculator was developed to estimate the 5-year survival probability for patients undergoing resection for ICC. This tool could help provide useful information to guide treatment decision-making and inform conversations about prognosis.