Abstract LB-146: The impact of pancreatic cancer resection on long-term survival in the era of effective systemic treatment

Abstract

Abstract Background: Surgical resection is the only curative modality in pancreatic cancer, yet the vast majority of patients undergoing surgery succumb of their disease. No large randomized studies have been performed to assess the survival impact of the procedure. We hypothesized that in the era of effective systemic treatments the survival advantage of surgical resection would be lessened. Methods: A meta-analysis of published phase II and phase III clinical trials in pancreatic cancer in both the post resection adjuvant setting and the locally advanced / metastatic setting. Trials were included based upon a systemic literature search. Eligibility criteria included: at least 50 patients per arm, detailed overall survival rates reported. Exclusion criteria: patients from trial arms for which there were not complementary data sets with / without surgical resection, trials testing non-pharmacological modalities or neoadjuvant approaches. Data was stratified based upon the systemic agents used, and analysed using an indirect aggregate approach. Primary endpoint was 3 year overall survival (OS_3yr), comparing patients treated with systemic treatment alone vs. surgery followed by adjuvant systemic treatment. Results: 74 treatment arms from 56 prospective trials published between 1990 and 2018 were included in the analysis. Overall a total of 11,898 patients were included, of whom 3,600 underwent resection. Median follow-up was 29.8 months for studies were stated. OS_3yr was for systemic treatment alone was 0%, 0%, 0.5%, 2.5%, 0.16%, 1.2%, 3.8% for No chemo, 5FU, Gemcitabine, S-1, Gemcitabine + xeloda, Gemcitabine + S-1, and Folfirinox respectively, and 19.9%, 24.9%, 32.9%, 58.8%, 42.5%, 52%, and 62.5% for the same agents delivered in the adjuvant setting; the advantage in OS_3yr provided by resection was 19.9%, 24.9%, 32.4%, 56.3%, 42.3%, 50.8%, and 58.8% for these agents, respectively. The advantage in OS_3yr provided by resection correlated closely with reported response rates for each systemic agent, r=0.96 p<0.001. Conclusions: Within the limitations of this analysis, it appears that our hypothesis was incorrect, and that the opposite is true. The introduction of effective systemic therapies has greatly increased the impact of pancreatic surgery on long-term survival in pancreatic cancer. Furthermore, it appears that for pancreatic cancer, systemic agents are more active in the adjuvant than the metastatic setting. Consequently, every effort should be made to bring patients to curative resection. Citation Format: Yaacov R. Lawrence, Alina Shtern, Ofer Margalit, Talia Golan, Zvi Symon. The impact of pancreatic cancer resection on long-term survival in the era of effective systemic treatment [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-146.