When cancer develops outside of the pancreas from within the anatomical placement of the pancreas itself, it becomes difficult to excise in most cases. Generally, most pancreatic cancers are already unresectable at the time of diagnosis when we have recognized infiltration of over 1/2 the circumference of major arteries such as the celiac artery and super mesenteric artery in particular.~In comparison with advanced pancreatic cancer with distant metastases, it is not easy to treat unresectable locally advanced pancreatic cancer, even when performing standard gemcitabine monotherapy. In the case of unresectable locally advanced pancreatic cancers without distant metastases, we are left with the choice of whether or not to perform radiation therapy. This decision remains unsolved worldwide, despite the continuing efforts of researchers to bring an end to the clinical doubt.~We will report our results as well as the problems of combining treatments with chemoradiotherapy, using the novel anticancer agent gemcitabine as well as/or S-1, not 5FU, predominantly from our own clinical trials on this occasion.
The purpose of this study is to evaluate the clinical effectiveness of Gemcitabine/S-1 combination chemoradiotherapy with Gemcitabine /S-1 combination chemotherapy for unresectable locally advanced pancreatic cancer.