K. Landa1, N. E. Farrow1, C. Rushing1, D. Niedzwiecki1, M. Cerullo1, R. Schmitz1, G. Herbert1, K. Shah1, S. Zani1, D. G. Blazer1, P. Allen1, M. Lidsky1 1Duke University Medical Center,Surgery,Durham, NC, USA
Introduction: Resectable pancreatic cancer is best treated with surgical resection (SR) and multiagent chemotherapy (MCT); however, many patients only complete a single modality due to treatment-related complications or disease progression. We aim to determine whether SR or MCT is associated with superior long-term survival for patients receiving single-modality therapy.
Methods: Patients with stage I-IIb pancreatic head adenocarcinoma who received either MCT (+/- radiation) or SR (pancreaticoduodenectomy/total pancreatectomy) alone were identified in the National Cancer Database (2013-2015). Patients who received single agent chemotherapy or had an unknown treatment status were excluded. Following a piecewise approach to estimating hazards over the course of follow-up, conditional overall survival (OS) at 30, 60, and 90 days after treatment initiation was estimated using landmark analyses.
Results: Of 5,146 eligible patients, 3,103 received MCT alone (60.3%) and 2,043 underwent SR alone (39.7%). SR had an OS disadvantage at 30 (HR 3.99, 95% CI 3.12-5.11) and 60 days (HR 1.85, 95% CI 1.4-2.45), but an OS advantage after 90 days (HR 0.59, 95% CI 0.55-0.64). In a landmark analysis conditioned on 90 days survival post treatment initiation (Figure), median OS was improved for SR (17.0 vs. 12.2 months, log-rank p<.0001); SR improved OS at 1 (+4.5%), 2 (+20.4%), 3 (+21.3%), and 4 (+15.3%) years (p<.05 for each difference), despite patients being older (median age 72 vs. 67 years, p<.0001) with higher Charlson-Deyo comorbidity scores (≥2: 11.2 vs. 8.6%, p=0.006).
Conclusion: For patients with resectable pancreatic cancer receiving single-modality treatment, SR was associated with superior long-term survival compared to MCT, supporting a role for upfront surgery in this population, especially those at risk of receiving a single therapy.
