O2-13-2 - The Prospective Study of S-1 + Gemcitabine and Concurrent Radiotherapy for Unresectable Locally Advanced Pancreatic Cancer

Abstract

Purpose: The aim of this study was to evaluate safety and efficacy of S-1 + gemcitabine (GEM) and concurrent radiotherapy in patients with unresectable locally advanced pancreatic cancer.Methods and Materials: Patients diagnosed with unresectable, locally advanced pancreatic cancer by histopathology or imaging were eligible. S-1 was administered orally at a dose of 60 mg/m2/day on day 1 - 14 and day 22 - 35. GEM was administered at a dose of 400 mg/m2/ 40 minutes (for the first 5 patients) and 300 mg/m2/ 60 minutes (for the remaining) by drip infusion on day 1, 8, 22, 29. Radiation therapy was concurrently delivered over 5.5 weeks at a total dose of 50.4 Gy (28 fractions). Adverse events were assessed by CTCAE version3.0. RECIST was done after the completion of chemoradiotherapy. The maintenance chemotherapy was not defined.Results: Twenty-five patients were enrolled in this study between January 2009 and March 2013. Median age was 68 (range 47 - 81). Men/Women: 11/14, PS 0/1/2: 12/12/1. Localization, head/body-tail: 11/14, Median tumor size was 43mm, cStage 2A/2B/3: 3/2/20. Twenty-one patients (84%) completed the planned treatment, 3 patients required a dose reduction of S-1 or GEM. One therapy-related death was observed. The grade 3/4 toxicities were leukocytopenia (60%), anemia (4%), thrombocytopenia (16%), febrile neutropenia (4%), anorexia (28%), nausea (4%) and fatigue (8%). The overall response rate and disease control rates were 25% (6/24) and 92% (22/24), respectively. The median progression-free survival and overall survival were 11.0 months and 16.0 months, respectively.Conclusions: S-1 + GEM and concurrent radiotherapy is active for unresectable locally advanced pancreatic cancer. Tolerability and efficacy of this regimen should be evaluated by a larger scale atudy.