[A case of locally advanced rectal cancer successfully resected after preoperative chemotherapy].

We present the case of a patient who was admitted because of acute pan-peritonitis but was found to have locally advanced rectal cancer that was successfully excised after preoperative chemotherapy. A 68-year-old man was transferred to our hospital via an ambulance because of severe lower abdominal pain. His abdominal computed tomography scan showed a huge tumor in the pelvis. An emergency sigmoid colostomy was performed because of panperitonitis. However, his postoperative examinations indicated locally advanced rectal cancer accompanied with extensive urinary bladder invasion but without distant metastasis, and chemotherapy was started. Eventually, the tumor reduced to 47% of its maximum size after 4 courses of FOLFOX6 and 2 courses of FOLFOX6+panitumumab, and radical excision( low anterior rectal resection, partial urinary bladder resection, D3 lymph node dissection, and total mesorectal excision) was performed on the 154th day since the first operation. No cancer cells were detected on microscopic analysis of the margins of the excised specimen. Thus, preoperative chemotherapy is useful for treating locally advanced rectal cancer.