[A Case of Long-Term Survival after Administration of Regorafenib for Stage Ⅳ Colorectal Cancer].

The patient was a 65-year-old man for whom a right hemicolectomy was performed for transverse colon cancer and multiple lymph node metastases. Peritoneal dissemination was observed throughout the abdominal cavity, and curative resection was not possible. Postoperative diagnosis: pT4bN2M1c(P3), Stage Ⅳc, and mutant RAS status. Therapy consisting of mFOLFOX6 plus bevacizumab was started 1 month after surgery, and up to 25 courses were completed. FOLFIRI plus bevacizumab therapy was performed up to 13 courses as the second-line therapy. Regorafenib 80 mg/day was started as the third-line therapy and the dose was gradually increased. It was performed up to 14 courses for about 13 months, without major adverse events, to keep the disease stable or slow its progression. Although up to 5 courses of FTD/TPI plus bevacizumab therapy were delivered as the fourth-line therapy, he died of disease progression. Regorafenib, which has been approved as a salvage line for metastatic colorectal cancer, features many adverse events, and there are few cases in which the approved dose can be administered. In our case, starting at a low dose resulted in fewer adverse events, adequate disease control, and long-term administration.