膀胱肉腫様癌の1例 : 組織発生に対する免疫組織化学的検討

Abstract

膀胱憩室内に発生した肉腫様癌例(82歳男)を経験した.本腫瘍の組織発生に対して病理組織学的及び免疫組織化学的検討を行い, 腫瘍は移行上皮癌の一部が腫瘍進展の過程において間葉系腫瘍への分化をとったものではないかと考えた.治療は膀胱部分切除術と左陰嚢水腫切除術を施行し, 術後経過は良好であったが, 消化管出血により全身状態は悪化し死亡した

An 82-year-old man with microhematuria and class V cells in his urinary cytologic specimen was referred to our clinic. Cystoscopy revealed a solid, broad-based tumor of 1 cm in diameter in the bladder diverticulum. A partial cystectomy was performed. The tumor was composed of transitional cell carcinoma (TCC), sarcomatous spindle cells and the area of transition between TCC and spindle cells. The histopathological diagnosis was sarcomatoid carcinoma. Immunohistochemical examination showed that the spindle cells and the area of transition were positive for keratin, cytokeratin, vimentin and muscle actin. The histopathological and immunohistochemical transitions between the TCC and the spindle cells suggested that the sarcomatous elements originated from the TCC during tumor progression.