Carbon-Ion Radiotherapy for Postoperative Locoregional Recurrence of Pancreatic Cancer

Abstract

To evaluate the efficacy and safety of carbon-ion radiotherapy (CIRT) for patients with locoregional recurrence after surgery for pancreatic cancer. A total of 32 patients, who underwent CIRT for locoregional recurrence after surgery for pancreatic cancer between January 2015 and July 2022, were retrospectively analyzed. The total dose of CIRT was 55.2 Gy (RBE) in 12 fractions. Concurrent chemotherapy included gemcitabine for 17 patients and S-1 for 3 patients. The overall survival (OS), local control (LC), progression free survival (PFS), and toxicity were evaluated. The median follow-up time from the initiation of CIRT was 21.4 months. The 1- and 2-year OS were 84.2 and 55.3%, respectively. The median survival were 24.2 months. The 1- and 2-year PFS were 40.7 and 14.8%, respectively, with a median PFS of 9.9 months. The 1- and 2-year LC were 100 and 50.2 %, respectively. 4 patients experienced grade 3 acute toxicities: hematologic toxicity in 2 patients, anorexia in 1 patient and gastric ulcer/bleeding in 1 patient. The patients with grade 3 gastric ulcer/bleeding underwent blood transfusion and recovered quickly. There was no grade 4 or 5 acute toxicity. In terms of late toxicity, no grade 3 or greater toxicity was observed. CIRT for postoperative locoregional recurrence of pancreatic cancer resulted in relatively long survival with acceptable toxicity. CIRT may be one of the choices of treatment for patients with this disease.