Randomized Phase Ii Study Of S-1 And Concurrent Radiotherapy With Versus Without Induction Chemotherapy Of Gemcitabine For Locally Advanced Pancreatic Cancer (Jcog1106)

4116 Background: Most patients (pts) with locally advanced pancreatic cancer (LAPC) are treated with chemotherapy (CT) alone in Japan. Chemoradiotherapy (CRT) is also a treatment option, but the role of radiotherapy (RT) remains controversial. Recently, induction CT followed by CRT is recognized as one potentially promising strategy. The aim of this study is to evaluate the efficacy and safety of CRT with and without induction CT to determine which is more promising CRT strategy. Methods: LAPC pts with an ECOG PS of 0-1, aged 20-80, and adequate organ function were randomized to CRT (Arm A) or induction CT followed by CRT (Arm B). Pts in Arm A received RT (50.4 Gy/28 fr over 5.5 weeks) with concurrent S-1 (40 mg/m²/dose, b.i.d. on the day of irradiation). Pts in Arm B received induction gemcitabine (GEM) (1,000 mg/m², iv, days 1, 8 and 15, every 4 weeks) for 12 weeks, and then, only pts with controlled disease received same CRT as Arm A. After CRT, GEM was continued until disease progression or unacceptab...