Background: A non-operative treatment strategy including chemoradiation (CRT) for rectal cancer, that is to say, watch and wait, is not currently recommended in Japan. However, some rectal cancer patients show a pathologically complete response after CRT. Watch and wait has been gradually applied in the U.S. and Western countries.
Case presentation: This case report describes a case report of a clinically complete response in a rectal cancer patient after CRT with a 2-year watch and wait approach. A 40-year-old woman suffered from cancer of the lower rectum without metastasis. Preoperative neoadjuvant CRT was thought to be indicated. The total dose of preoperative radiotherapy was 50.4 Gy, which was given in a fractionated manner over a long time period (1.8 Gy×28 Fr over 6 weeks). She took tegafur-uracil (300-500mg/day) and leucovorin (75mg/day) concurrently with radiotherapy. Two months after the end of CRT, colonoscopy showed a remarkable reduction of the tumor. Although we explained to the patient the content of the surgical therapy with lymph node dissection and the possibility of stoma creation, she refused to undergo the surgery. Therefore, we planned to perform a follow-up including measurement of tumor markers, colonoscopy, and CT. She has kept a clinically complete response for two years since the end of CRT.
Conclusions: The present case showed the possibility that a watch and wait strategy might be applicable to some rectal cancer cases.
症例は88歳女性．２カ月前からの食思不振，嘔気を自覚し近医受診後，精査目的に当院紹介となった．当院初診時，症状は心窩部の圧痛のみであった．上部消化管内視鏡検査にて胃穹窿部前壁，体下部小彎側に壁外性圧迫を認めた．単純腹部CTでは，胃小彎側に膵・肝に囲まれるように11cm大の腫瘤性病変を認めた．超音波内視鏡検査にて，胃体下部に筋層と境界が不明瞭な領域があり，胃原発の消化管間質腫瘍（Gastrointestinal stromal tumor）との診断で手術を施行した．術中所見にて，腫瘍は胃小彎側・膵体尾部に接しており，幽門側胃切除術，膵体尾部切除術，脾臓摘出術を施行した．術後病理診断にてMixed acinar-endocrine cell carcinoma of the pancreasとの診断に至った．術後半年の時点で再発，転移なく経過している．