Real-world assessment of treatment sequencing of patients with advanced biliary tract cancer in a private practice in Rio de Janeiro and São Paulo, Brazil.

Abstract

587 Background: Biliary tract cancer, including cholangiocarcinoma and gallbladder carcinoma, have low incidence and poor prognosis. Despite representing a heterogeneous group, the studies encompass these malignancies as the same entity. There are few phase III trials that evaluate treatment sequencing in the metastatic setting. The ABC 02 trial showed an increase in overall survival (OS) with Gemcitabine and Cisplatin (GemCis) in first line and the ABC 06 trial an increase in OS in second-line Folfox. Recently, the TOPAZ 1 trial demonstrated benefit of first-line immunotherapy. The primary objective of this study was OS in patients with advanced cholangiocarcinoma according to treatment. The secondary objective was to analyze the patients characteristics. Methods: Retrospective analysis of medical records from two private institutions. Patients were eligible if they had advanced intra or extra cholangiocarcinoma or gallbladder carcinoma, undergoing chemotherapy from January of 2015 to January of 2021. Results: Database included 82 patients with intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma or gallbladder carcinoma, 54%, 23% and 23%, respectively. Median age was 65 years old, with an equal proportion between sexes. 75% had metastasis at diagnosis and 12 patients (14%) underwent more than two lines of treatment. Median OS was 288 days. GemCis was the most common first line protocol (62%), followed by Gemcitabine and Oxaliplatin (17%). There was no difference in OS between the regimens, regardless of the primary site. Folfiri and Folfox were used in the same proportion in second line (17% for each), but with a significant increase in OS for Folfiri (485 days vs. 368 days, p=0.02), regardless of the primary site. According to univariate analysis of factors associated with mortality, the significant variables were: surgery for primary site (HR 0.49 [95% CI 0.28-0.85]; p=0.01), metastasis at diagnosis (HR 1.89 [95% CI 1.10-3.25]; p=0.02), liver metastasis at diagnosis (HR 1.69 [95% CI 1.02-2.80]; p=0.04), and more than two lines of treatment (HR 0.41 [95% CI 0.21-0.80]; p=0.009). Conclusions: Despite being retrospective and not using first-line immunotherapy, this study was able to demonstrate no difference in OS between first-line regimens with GemCis or Gemcitabine and Oxaliplatin. However, when analyzing second-line sequencing, Folfiri demonstrated benefit independent of the primary site.