Duration of therapy for locally advanced pancreatic cancer: Does it matter?

Introduction: Evidence-based recommendations on duration of multiagent systemic therapy for LAPC are lacking. Herein, we assess the impact of duration of combination systemic therapy on survival of patients with LAPC.

Methods: The National Cancer Database was interrogated to identify patients with untreated LAPC diagnosed from 2004 to 2014. Patients treated with ≥ 1 month of multiagent chemotherapy (MAC) and ≥ 6 months of follow-up were included. Kaplan-Meier survival curves were generated to examine OS of each MAC duration group. Univariable and multivariable Cox proportional hazards regression was used to examine the association between OS with demographic and clinical variables. Statistical computations were performed using SAS Software Version 9.4.

Results: Of the 3410 patients, 1114 met inclusion criteria. Median age was 64 years. Median treatment duration was 3.2 months (range 1-19.8). Median follow-up was 23.5 months (range 3-120). Median OS of all patients was 9.4 months (95% CI: 8.7-10.1). Median OS of patients receiving ≥ 1-4 months, >4-6 months and > 6 months of MAC was 8.4 months (95% CI: 7.7-9), 10.2 months (95% CI: 9-11.8), and 12.8 months (95% CI 11.6-16). Twelve-month survival was 37% for patients receiving ≥ 1-4 months, 43% for > 4-6 months, and 56% for > 6 months. Female sex (P = .02), higher median household income (P = .03), and longer duration of MAC (P < .001) were independently associated with improved OS following multivariable analysis.

Conclusion: This analysis in LAPC patients suggests that combination systemic therapy regimens of 6 months or more may optimize survival outcomes. Further investigation on the duration of systemic therapy question in LAPC is needed.