巨大直腸平滑筋肉腫の1例

Giant Rectal Leiomyosarcoma, Report of a Case

要旨　患者は63歳，男性．前立腺肥大の治療中，肛門出血のために紹介となった．大腸ファイバースコープおよび注腸検査にて，直腸前壁に多発する潰瘍を伴った巨大腫瘍を認めた．潰瘍底からの生検診断ではleiomyomaであったが，腫瘍の大きさ，大量出血，潰瘍形成などの臨床所見から臨床的に悪性化を強く疑い，骨盤内臓全摘術を施行したところ，摘出標本の病理組織所見ではleiomyosarcomaであった．

　A 63-year-old man was admitted to our department with the chief complaint of anal bleeding after defecation. By the digital examination a solid mass larger than child's fist size was felt in the anterior wall of the rectum. Endoscopically a semispherical tumor suggesting a submucosal one with some ulcers was observed. Barium enema showed marked narrowing of the ampulla region of the rectum. Biopsy specimen was diagnosed as leiomyoma, but clinically leiomyosarcoma was suspected. A total pelvic exenteration was performed. The submucosal tumor was measured 16×10×7 cm, with ulcers on the mucosal surface, and its cut surface was white and solid with a few necrotic areas. A histopathologic examination showed that the tumor was leiomyosarcoma.