直腸lipoid granulomaの1例

Lipoid Granuloma of the Rectum, Report of a Case

要旨　患者は82歳，男性．便秘を主訴に近医受診．肛門腫瘍の診断で当院へ紹介となった．直腸指診で直腸肛門全周に粘膜下腫瘍様の腫瘤を触知し，生検で粘液腺癌の疑いを得て，腹会陰式直腸切断術を施行した．病理組織学的所見では腫瘍性変化を認めず，lipoid granulomaと診断された．直腸lipoid granulomaはまれな疾患で一般に結節状の粘膜下腫瘍様の形態をとるものが多いが，全周性の病変では腸管狭窄を来し直腸癌に類似した形態をとることがある．直腸粘膜下腫瘍，直腸肛門癌とりわけ管外型肛門管癌の鑑別疾患として念頭に置く必要がある．

　An 82-year-old male consulted a local clinic for constipation. Under a diagnosis of an anal tumor, the patient was referred to our hospital. Digital examination of the rectum revealed a submucosal tumor-like phyma involving the circumferential rectum and anus. A biopsy suggested mucinous carcinoma. Abdominoperineal resection of rectum was performed. Histopathological findings did not show any tumorous changes, suggesting lipoid granuloma. Lipoid granuloma of the rectum is rare, and many lesions generally show a nodular submucosal tumor-like morphology. However, in some circumferential lesions, the morphology resembles that of rectal cancer due to stenosis. This tumor should be considered as a disease to be differentiated from submucosal rectal tumors and rectal cancer.