A case of a patient with advanced rectal cancer and urinary bladder fistula surviving for 6 years after chemoradiotherapy without surgery

: A 60-year-old man with advanced rectal cancer and urinary bladder fistula received preoperative chemoradiotherapy with S-1(120mg/m / 2day)on weekdays and concurrent radiotherapy(65 Gy). After chemoradiotherapy, the clinical symptoms resolved and the tumor shrunk, as observed on endoscopic and radiologic examinations. However, remnant cancer was suspected; therefore, modified oxaliplatin, 5-fluorouracil, and Leucovorin(mFOLFOX6)therapy was initiated, although it was stopped after 3 cycles because of numbness in the lower extremities. Finally, clinical and pathological complete response(CR) was achieved by administering additional doses of S-1 for approximately 1 year after treatment initiation; CR was confirmed by using endoscopy and computed tomography(CT), and there has been no recurrence for 6 years. This case suggests that treatment without surgery is a viable alternative for advanced rectal cancer with pathological CR after chemoradiotherapy.