Background: Despite randomized trials addressing adjuvant therapy (AT) for pancreas cancer, the ideal time to initiate therapy remains undefined. Retrospective analyses of the ESPAC-3 trial demonstrated that time to initiation of AT did not impact overall survival (OS). Given the absence of confirmatory data outside of a clinical trial, we sought to determine if AT timing in routine clinical practice is associated with OS differences.
Methods: Perioperative data of pancreatectomies for ductal adenocarcinoma from five institutions (2005-2015) were assessed. Delay in AT was defined as initiation >12 weeks after surgery. Multivariate analysis was performed to identify predictors of mortality.
Results: Of 867 patients, 172 (19.8%) experienced omission of AT. Improved OS was observed in patients who received AT compared with patients who did not (24.8 vs. 19.1 months, p < 0.01). Information on time to initiation of AT was available in 488 patients, of whom 407 (83.4%) and 81 (16.6%) received chemotherapy ≤12 and >12 weeks after surgery, respectively. There were no differences in recurrence-free survival or OS (all p > 0.05) between the timely and delayed AT groups. After controlling for perioperative characteristics and tumor pathology, patients who initiated AT ≤ 12 or > 12 weeks after surgery had a 50% lower odds of mortality than patients who only underwent resection (p < 0.01).
Conclusions: In a multi-institutional experience of resected pancreas cancer, delayed initiation of AT was not associated with poorer survival. Patients who do not receive AT within 12 weeks after surgery are still appropriate candidates for multimodal therapy and its associated survival benefit.