Safety and efficacy of stereotactic body radiation therapy combined with S-1 simultaneously followed by sequential S-1 as an initial treatment for locally advanced pancreatic cancer (SILAPANC) trial: study design and rationale of a phase II clinical trial

摘要

IntroductionUpfront surgeries are not beneficial to most patients with pancreatic cancer. Therefore, more emphasis has been placed chemoradiotherapy in locally advanced pancreatic cancer recently. Gemcitabine-based regimens or FOLFIRINOX (a chemotherapy regimen including leucovorin, 5-FU, irinotecan, oxaliplatin) has been proven as a standard chemotherapy in pancreatic cancer. However, severe toxicities may prevent the completion of chemotherapy. S-1 has showed better objective response rates, similar overall survival rates and progression-free survival rates compared with gemcitabine, revealing that S-1 may be a potential candidate in treating pancreatic cancer, especially for patients refractory to gemcitabine. Additionally, stereotactic body radiation therapy with Cyberknife could provide better efficacy than conventional radiotherapy in pancreatic cancer. Therefore, Cyberknife with S-1 simultaneously followed by sequential S-1 as an initial treatment may bring about favourable outcomes but needs further studies.