Adjuvant chemotherapy for resected intrahepatic cholangiocarcinoma confers no survival advantage.

Abstract

560 Background: Randomized data suggest improved survival with adjuvant chemotherapy for biliary tract cancers, but subset analyses of intrahepatic cholangiocarcinoma (ICC) show limited survival benefit. This study uses a large bi-institutional cohort of resected ICC patients to evaluate the impact of adjuvant therapy on recurrence patterns and overall survival (OS) and compares these findings to data from a national cancer registry. Methods: Patients with resected ICC were identified within a bi-institutional cohort (Duke and Memorial Sloan Kettering, 1997-2020) and the National Cancer Database (NCDB, 2010-2018). Patients were stratified by treatment with adjuvant chemotherapy (adj). Site of first recurrence was categorized as local (liver only), regional (liver and perihepatic nodes), nodal (perihepatic nodes only), distant, or mixed (both liver and distant). OS was compared with Kaplan-Meier methods. Results: 367 patients underwent resection for ICC, and 163 (44%) patients received adjuvant therapy. Median follow-up was 33 vs. 44 months (adj vs observation (obs), p=0.15). 263 (72%) patients had recurrent disease, most commonly in the liver (72%). There was no difference in recurrence patterns stratified by treatment with adjuvant chemotherapy (% recurrence, adj vs obs; local: 42 vs 42; regional: 2 vs 2; nodal: 0 vs 3; distant only: 27 vs 26; mixed: 29 vs 27, p=0.5). OS was the same between groups (adj vs obs; 42 vs 49 months, p=0.3) and when stratified by recurrence site (p=0.5). Similarly, in an NCDB cohort of 1,159 ICC patients over the same time period, there was no association between adjuvant therapy and OS (adj vs obs; 49 vs 57 months, p=0.1). Conclusions: In this retrospective dual registry analysis, corroborated by national data, adjuvant chemotherapy was not associated with an improvement in OS in ICC patients subjected to curative intent resection. Further, adjuvant therapy had no impact on the high rate of hepatic recurrence, suggesting that alternative strategies, such as liver directed therapies, are needed to improve recurrence rates and OS.