Prognosis Of Resectable Pancreatic Cancer Based On Systemic Therapy Sequence And Regimen: An Ncdb Analysis.

4120 Background: While surgical resection can cure pancreatic cancer (PC), the majority of patients who undergo resection recur. As newer multi-agent chemotherapy regimens have evolved for metastatic PC, there has been increased interest in its use in the neoadjuvant (NAT) setting. However, U.S. clinical practice patterns vary widely. We evaluated the effect of systemic therapy sequence and regimen on prognosis in resected PC. Methods: Adult patients with resected, clinical stage I or II PC were identified in the NCDB from 2010-2015. Patients who received NAT followed by resection were matched by a minimum distance approach with those who underwent upfront resection (UR) with or without adjuvant therapy (AT) based upon demographics and disease-specific variables. OS was compared with Kaplan-Meier curves in matched cohorts. The effects of single-agent (SA) versus multi-agent (MA) chemotherapy (CT) on OS was evaluated using multivariate Cox proportional hazards regression model. Results: We identified 23,576 patients with clinical stage I or II resected PC. 3,446 patients who received NAT were matched with 3,446 patients who underwent UR. Those who received NAT had improved OS compared to those who underwent UR with or without AT (median survival time [MST] 27.9 versus 23.3 months, respectively; log-rank p < 0.0001). Among different treatment sequences, patients who received both NAT and AT had the longest OS compared to those who received either NAT or AT alone (MST 31.3 versus 26.2 versus 26.5 months, respectively; log-rank p < 0.0001). In patients treated with NAT alone, those who received MA CT had an improved OS compared to those who received SA CT (adjusted HR 0.72, 95% CI 0.64-0.81). In patients who received MA chemotherapy, MA NAT was associated with an 18% reduction in risk of death compared to those treated with MA AT (adjusted HR 0.82, 95% CI 0.73-0.93). Conclusions: In resectable PC, patients who received both NAT and AT had improved survival compared to those who receive NAT or AT alone. This supports future evaluation of maintenance therapy in the adjuvant setting. MA NAT was associated with improved survival compared to SA NAT. This supports current clinical practice and ongoing clinical trials.