Evaluation of predictive variables in locally advanced pancreatic adenocarcinoma patients receiving definitive chemoradiation

Abstract

To analyze a single-center experience with locally advanced pancreatic cancer (LAPC) patients treated with chemoradiation (CRT) and to evaluate predictive variables of outcome. LAPC patients at our institution between 1997 and 2009 were identified (n = 109). Progression-free survival (PFS) and overall survival (OS) were assessed using Kaplan-Meier analysis. Cox proportional hazard models were used to evaluate predictive factors for survival. Patterns of failure were characterized, and associations between local progression and distant metastasis were explored. Median OS was 12.1 months (2.5-34.7 months) and median PFS was 6.7 months (1.1-34.7 months). Poor prognostic factors for OS include Karnofsky performance status ≤80 (P = .0062), treatment interruption (P = .0474), and locally progressive disease at time of first post-therapy imaging (P = .0078). Karnofsky performance status ≤80 (P = .0128), pretreatment CA19-9 >1000 U/mL (P = .0224), and treatment interruption (P = .0009) were poor prognostic factors for PFS. Both local progression (36%) and distant failure (62%) were common. Local progression was associated with a higher incidence of metastasis (P < .0001) and decreased time to metastasis (P < .0001). LAPC patients who suffer local progression following definitive CRT may experience inferior OS and increased risk of metastasis, warranting efforts to improve control of local disease. However, patients with poor pretreatment performance status, elevated CA19-9 levels, and treatment interruptions may experience poor outcomes despite aggressive management with CRT, and may optimally be treated with induction chemotherapy or supportive care. Novel therapies aimed at controlling both local and systemic progression are needed for patients with LAPC.