A Phase Ii Clinical Trial Of Carbon-Ion Radiotherapy And Concurrent S-1 Chemotherapy For Locally Advanced Pancreatic Cancer

TPS504 Background: Despite recent advances in chemotherapy and radiotherapy, prognosis of unresectable locally advanced pancreatic cancer (LAPC) patients remains poor. To improve the outcome, a phase I/II clinical trial of carbon-ion radiotherapy (CIRT) with concurrent gemcitabine for LAPC was started in National Institute of Radiological Sciences in Japan.When compared to photon beams, carbon ion beams offer improved dose distribution, enabling us to concentrate a sufficient dose within a target volume while minimizing the dose in the surrounding radiosensitive normal tissue. In addition, carbon ions being heavier than protons provide a higher biological effectiveness, which increases with depth reaching the maximum at the end of the beam’s range. Although CIRT is expected to offer powerful local effect, whereas the potential risk of distant metastasis represent a critical problem for LAPC. To control distant metastases and subsequently prolong patient survival, a more effective systemic treatment might ...