Isolated metastatic tumor of rectosigmoidal colon originated from primary small intestinal cancer

症例は42歳男性.腸閉塞に対する精査CTにて小腸腫瘍を認め腹腔鏡下空腸部分切除術を行った.術中の病理検索で原発性小腸高分化型線癌と確定診断され,術後は最終病期fStageIIIaに対して大腸癌の補助化学療法レジメに則りCapecitabine+ Oxaliplatine(CapeOX)療法を6ヵ月間施行した.しかしながら術後1年4ヵ月目の下部消化管内視鏡検査にて直腸S状部に発赤を呈した粘膜下腫瘍様の隆起性病変が認められ,生検病理組織診断は前回の小腸癌細胞とほぼ一致した.CT検査においても同部位に腫瘤形成を認め単発の病変であった.よって原発性小腸癌の異時性かつ孤立性に発生した直腸S状部転移と診断し腹腔鏡下直腸高位前方切除術を施行した.病理組織学的･免疫学的検索では漿膜下から粘膜下層にわたり既往の小腸癌と類似した腫瘍細胞の増生を認めた.現在,追加の化学療法は行わず厳重に経過観察中である.今回われわれは小腸癌根治術後,異時性に孤立性直腸S状部転移を来した非常に稀な原発性小腸癌1例を経験したので文献的考察を加えて報告する.

The patient is a 42-year-old man. The CT scan for intestinal obstruction revealed tumor of the small intestine and laparoscopic partial jejunectomy was performed. The pathological diagnosis was well-differentiated adenocarcinoma of the primary small intestine. Reffering to the regimen of adjuvant chemotherapy in colorectal cancer. Capecitabine+Oxaliplatine(CapeOX)therapy was performed for six months after first operation. However, new lesion located at the rectosigmoidal(RS)colon was found after one year and four months by colonoscopy. It seems about submucosal tumor with mucosal reddening. The finding by cytologic examination was nearly consistent with the cells of the previously diagnosed cancer of the small intestine. The CT scan revealed single mass forming lesion at the same location. Therefore, we diagnosed as heterochronic and isolated metastasis to the RS colon from primary cancer of the small intestine. Laparoscopic high anterior resection of the rectum was performed. In histopathological and immunohistochemical analyses, tumor cells previously diagnosed was identified from the subserosa to submucosa. No additional chemotherapy was performed and he is under the intensive follow-up.

原発性小腸癌

結腸転移

直腸転移

腹腔鏡下手術