Safety and efficacy of chemotherapy in older adults with locally advanced and metastatic pancreatic ductal adenocarcinoma (PDAC).

Abstract

654 Background: PDAC is often diagnosed in patients (pts) ≥75yrs. However, older adults comprise a small proportion of subjects in prospective trials, and there is little reported on the safety and efficacy of chemotherapy in this population. Methods: Records were reviewed on all pts ≥75yrs treated with chemotherapy for locally advanced and metastatic PDAC at a single institution from April 2010 - March 2018. Response rate (RR), progression free survival (PFS), overall survival (OS) and toxicities were compared among the different regimens, and among pts < or ≥80yrs. Survival was estimated with the Kaplan-Meier method and compared by log-rank test. Univariate analyses were performed by Fisher’s exact test and multivariate analyses by a Cox-regression model to identify factors associated with PFS and OS in this population. Results: 67 pts were treated, median age 81yrs (range: 75-90), stage III (34, 51%) and IV (33, 49%). Chemotherapy regimens included: gemcitabine alone (39), gemcitabine/nab-paclitaxel (17), gemcitabine/vinorebine (1), FOLFOX (8) and FOLFIRINOX (2). 59 (88%) pts required dose adjustments due to toxicity; no differences by age or regimen. RR, PFS, and OS did not differ by age or regimen (Table), although sample size was small. Age >80yrs was associated with reduced PFS (p 0.03). On univariate analyses liver metastases and performance status (PS)>1 were associated with reduced OS; PS>1 was associated with reduced OS on multivariate analysis. Conclusions: Among pts with locally advanced and metastatic PDAC ≥75yrs, there were no differences in RR, PFS or OS by chemotherapy regimen. PS was the only variable associated with reduced OS. Older adults with PS 0-1 are likely to benefit from chemotherapy for non-resectable PDAC.[Table: see text]