膀胱小細胞癌の1例

Abstract

72歳男.術前診断で膀胱内限局性腫瘍の診断のもと経尿道的膀胱腫瘍切除術(TURBT)を施行した.15ヵ月後, 同部位に腫瘍の再発を認め, TURBTを施行した.さらに69ヵ月後, 同部位に腫瘍を認めため精査加療目的で入院した.深達度はT2以上と考えられたが, 遠隔転移を疑う所見は認めなかった.術前化学療法で全身性MVAC変法2コース施行したが腫瘍径は不変で, TURBTを施行しその後, 膀胱全摘除術, 自排尿型代用膀胱造設術を施行した.膀胱小細胞癌と診断され, 免疫組織化学染色では神経内分泌癌と考えられた.多発性肺転移を認め, 化学療法と局所放射線を施行したが10ヵ月目で死亡した

A 72-year-old man presented with gross hematuria. Cystoscopy showed a non-papillary tumor at the right side of the posterior wall. Transurethral resection of the bladder tumor (TURBT) was performed. Pathologic findings demonstrated superficial transitional cell carcinoma (TCC). However, recurrent tumors were detected at the same location after 69 months' follow up. TURBT was done for the biopsy and pathologic examination showed muscle-invasive TCC. After two courses of neoadjuvant chemotherapy (MVAC), we performed radical cystectomy with Hautmann's continent reservoir. Pathologic findings revealed small cell carcinoma without any TCC features. Immunohistochemical staining using chromogranin A and synaptophysin was positive in the latest TURBT and the radical cystectomy specimens. We report a case of primary small cell carcinoma transformed from TCC of the urinary bladder.