P-220 - Efficacy of oxaliplatin, irinotecan and erlotinib use regarding overall and progression-free survival in gemcitabine-based chemotherapy for locally advanced and metastatic pancreatic cancer

Abstract

Introduction: Gemcitabine-based therapy has been used as first-line treatment for patients with unresectable locally advanced or metastatic pancreatic cancer. Several combinations of gemcitabine with multiple agents have been tested in the past few years giving a survival benefit, especially when erlotinib is added to gemcitabine-based therapy. The purpose of this study is to provide survival data coming from gemcitabine-based combination regimens. Methods: Clinicopathological data of patients with unresectable locally advanced or metastatic pancreatic cancer who had received gemcitabine-based therapy during 2002-2010 were identified from a prospectively collected database and were retrospectively analyzed according to their treatment arm. Progression-free survival (PFS) and overall survival (OS) were evaluated as primary outcomes. Results: A total of 318 patients with locally advanced or metastatic pancreatic cancer were identified. Mean age of the study group was 63.7 years old, whereas 40.9% of the patients were women and 51.4% of all tumors were located in the head of the pancreas. Gemcitabine was omitted alone (G Group [N = 67]], PS 0/1/2 26.9%/56.7%/16.4%) or in combination with erlotinib (G+E Group [N = 110], PS 0/1/2 47.3%/43.6%/9.1%), erlotinib and oxaliplatin (G+E+0 Group [N = 51], PS 0/1/2 37.3%/47.1%/15.6%), oxaliplatin (G+O Group [N = 24], PS 0/1 54.2%/45.8%), and finally irinotecan (G+I Group [N = 66], PS 0/1/2 24.2%/63.6%/12.2%),). Median PFS was 6 months in the G+E group, 5.3 in the G+E+0 group, 5.5 months in the G+O groups, 3.5 months regarding the G+I group and 2.9 months concerning the G group (Log-Rank test<0.001). Median OS was 11.2 months in the G+E group, 10 months in the G+E+O group, 8.5 months in the G+I, 8 months in the G+O group and 6.7 months in the G group (Log-Rank test=0.016). PFS was significantly higher in the G+E group (HR: 0.51, 95%[CI]: 0.36-0.71, P < 0.001), G+E+O group (HR: 0.46, 95%[CI]: 0.31-0.70) and G+O group (HR: 0.54, 95%[CI]: 0.32-0.91, P = 0.021). OS was significantly higher in the G+E group (HR: 0.6, 95%[CI]:0.41-0.87, P = 0.006) and G+E+O group (HR:0.53, 95%[CI]: 0.33-0.84, P = 0.007). Conclusion: The present results support the beneficial effect of erlotinib use regarding overall and progression-free survival. The addition of oxaliplatin in gemcitabine-based chemotherapy appears to contribute in the first five months but does not seem to improve overall survival.