Preoperative chemoradiotherapy to improve overall survival in pancreatic cancer: Long-term results of the multicenter randomized phase III PREOPANC trial.

Abstract

4016 Background: Preoperative chemoradiotherapy (CRT) may improve overall survival in resectable pancreatic cancer (RPC) and borderline resectable pancreatic cancer (BRPC). Long term results are presented. Methods: In this multicenter phase III trial, patients with RPC or BRPC were randomized between preoperative CRT, (gemcitabine 1000 mg/m2 weekly for 7 of 10 weeks, and 15x2.4 Gy radiotherapy in week 4 to 6), followed by surgery and four cycles of adjuvant gemcitabine (1000 mg/m2 weekly for 3 of 4 weeks), or immediate surgery followed by 6 cycles of adjuvant gemcitabine (1000 mg/m2 weekly for 3 of 4 weeks). Primary endpoint was overall survival by intention-to-treat (ITT). Results: From April 2013 to July 2017, 246 eligible patients were accrued by 16 Dutch centers and randomized, 119 to preoperative CRT and 127 to immediate surgery. After a median follow up of 56 months (35.3-92.0 months), 210 patients have died, 93 (78%) in the preoperative CRT arm and 117 (92%) in the immediate surgery arm. Three- and five-year overall survival ITT was 27.7% and 20.5% after preoperative CRT versus 16.5% and 6.5% after immediate surgery (HR 0.73; 95% CI 0.56 to 0.96; p = 0.025). In addition, disease-free survival (HR 0.70; p = 0.009) locoregional failure-free interval (HR 0.57; p = 0.004) and distant metastases free interval (HR 0.74; p = 0.071) improved after preoperative CRT. Also in the stratified subsets RPC and BRPC, preoperative CRT improved OS: RPC (n = 133, HR 0.79; 95% CI 0.54 to 1.16; P = 0.23). BRPC (n = 113, HR 0.67; 95% CI 0.45 to 0.99; p = 0.045). We could not demonstrate a difference in treatment effect between these subsets (interaction test p = 0.56). Conclusions: Preoperative gemcitabine-based CRT for RPC or BRPC improves long term overall survival compared to immediate surgery with adjuvant gemcitabine. Clinical trial information: NTR3709.