Clinical utility of comprehensive genomic profiling and targeted therapy in biliary tract cancers: A real-world experience.

Abstract

e16671 Background: Biliary tract cancers (BTC) are a highly aggressive group of malignancies with high mortality and poor prognosis. Chemotherapy is the mainstay of treatment for advanced disease. The role of molecular targeted therapy and immunotherapy using comprehensive genomic profiling (CGP) is evolving. We investigated the role of CGP directed therapy in patients with BTC. Methods: A multi-center retrospective study of CGP done on 35 patients with BTC at Sanford USD Medical Center and Avera McKennan Hospital, Sioux Falls, SD, between 2014 and 2019. 27 patients had cholangiocarcinoma (fifteen intrahepatic, two extrahepatic and ten unclassified), two had gallbladder carcinoma and six had ampullary carcinoma. Results: 22 of 35 BTC (63%) had potentially actionable genetic alterations(GA). Nine of these 22 (41%) received molecular therapy based on CGP. Four patients had microsatellite instability (MSI-H) and two of them received immunotherapy (Table). CDKN2A/B was the most common mutation (23%) followed by PIK3CA (13%), ARID1A (13%) and Tp53(13%). By the end of the follow up period, median overall survival (OS) was 569 days(19 months) for those who received targeted therapy compared to 315 days(10.5 months) for those who did not. (P = 0.051). Conclusions: In this multi-center cohort, 63% of patients had at least one targetable GA. Furthermore, CGP guided treatment decisions in 41% of patients. CGP has the potential to provide clinically meaningful treatment options for patients with BTC. New studies are warranted to further investigate this promising prospect for BTC management. [Table: see text]