Second-line chemotherapy (2L) in elderly patients with advanced biliary tract cancer (ABC): A multicenter real-world study.

Abstract

322 Background: The ABC-06 trial recently established the role of 2L in ABC progressing after platinum/gemcitabine combination. However, older patients are often under-represented in clinical trials and no data are currently available regarding 2L in elderly ABC. The aim of this real-world study was to explore the treatment pattern, safety and efficacy of 2L in ABC patients aged ≥ 70 years old and to compare their outcomes with younger subjects. Methods: Institutional registries across three academic medical centers were retrospectively reviewed and data of interest retrieved to identify ABC who had received 2L from October 2002 to July 2020. Patients older than 70 years were considered as elderly individuals. The Kaplan-Meier methods was used to estimate survival and the log-rank test to make comparison. The impact of variables on survival was assessed through univariate and multivariate analysis. Results: A total of 190 ABC patients treated with 2L were identified and included in the analysis. Among them, 27.3% (n = 52) were aged ≥ 70 years (range 70-87y), of whom 25 patients had iCCA (48%), 13 GBC (25%) and 15 eCCA (27%). 56% (n = 29) were female and 38 (73%) patients had an ECOG-PS 0-1. The most frequently administered 2L regimens were capecitabine monotherapy (n = 14, 27%), single-agent gemcitabine (n = 9, 17%) and gemcitabine/capecitabine combination (n = 9, 17%). No differences in terms of prior surgery (p = 0.64) and 2L treatment intensity (p = 0.34) were observed compared to patients aged < 70 years. The disease control rate of 2L was 28.8% and 29.7% in elderly and youngers, respectively. No statistically significant differences in both mOS (5.7 months in elderly vs 6.1 months in youngers, HR 0.97; p = 0.86) and mPFS (4.7 vs 4.8 months, HR 0.88; p = 0.44) were recorded. Regarding the safety profile of 2L, grade 3 or 4 treatment-related toxicities occurred more frequently in the older group (48.5% versus 8.2%; OR 6.31; p < 0.001). When looking at prognostic factors, absolute lymphocyte count < 1000/mmc (p < 0.001) and albumin level < 3 g/dL (p < 0.001) were independently associated with worse prognosis. Conclusions: The results of this real-world study, limited by its retrospective nature and small sample size, suggest that for patients aged ≥ 70 years, 2L could be equally effective as for youngers, with survival outcomes aligned to those from ABC-06 trial. Notably, based on the higher incidence of grade 3-4 adverse events, the delivery of 2L should be carefully evaluated and monitored in this patient subset.