Effect of Chemoradiotherapy on Locoregional Recurrence After Pancreatectomy for Pancreatic Cancer

Background/Aim: The study aimed to investigate the efficacy of radiotherapy or chemoradiotherapy for isolated locoregional recurrence after pancreatectomy for pancreatic cancer. Patients and Methods: Twenty-eight patients who had isolated locoregional recurrence after pancreatectomy for pancreatic cancer between 2007 and 2021 were retrospectively analyzed. We investigated the effect of the treatment method [radiotherapy or chemoradiotherapy (radiotherapy with concurrent chemotherapy)] on progression-free survival (PFS) and post-recurrence survival (PRS). Results: The median disease-free survival was 16.1 months (range=4.7-47.1 months). Five patients received radiotherapy and 21 patients received chemoradiotherapy [radiotherapy concurrent with gemcitabine (GEM) or S-1] for locoregional recurrence. All patients except one patient with interstitial pneumonia were treated with salvage chemotherapy after irradiation. The median PFS rates of the radiotherapy group and the chemoradiotherapy group were 2.8 months (range=1.5-5.4 months) and 16.8 months (range=2.7-42.8 months), respectively. The median PRS rates were 23.7 months (range=8.1-26.4 months) for the radiotherapy group and 26.2 months (range=6.0-64.7 months) for the chemoradiotherapy group. Multivariate analysis identified radiotherapy [hazard ratio (HR)=12.2, 95% confidence interval (CI)=3.29-45.6, p<0.001] and serum DUPAN-2 >150 U/ml (HR=2.90, 95%CI=1.22-6.93, p=0.02) as independent predictors of PFS, and UICC TNM Stage >= III (HR=3.23, 95%CI=1.17-8.96, p=0.02) and modified Glasgow prognostic score before the treatment for the recurrence 1 or 2 (HR=3.05, 95%CI=1.15-8.08, p=0.03) as independent predictors of PRS. Conclusion: Chemoradiotherapy for isolated locoregional recurrence after pancreatectomy for pancreatic cancer could suppress re-recurrence more effectively than radiotherapy.