膀胱Plasmacytoid Carcinomaの1例  [in Japanese] PLASMACYTOID UROTHELIAL CARCINOMA OF THE BLADDER: A CASE REPORT  [in Japanese]

我々は膀胱Plasmacytoid Carcinomaの1例を経験した.患者は頻尿を主訴とする79歳男性であり,各種検査にて膀胱内に広範囲に存在する浸潤性膀胱腫瘍を認めた.TUR-BTを施行し,病理組織において筋層および粘膜固有層内に浸潤する小型の腫瘍細胞のびまん性増殖を認めたため,浸潤性膀胱癌の診断にて膀胱全摘除術を施行した.右閉鎖リンパ節転移を認めたことから,M-VAC療法を2コース施行.11ヵ月経過した現在再発を認めていない.腫瘍細胞は,円形小型,豊富な好酸性の細胞質および核の偏移といった形質細胞腫に類似した組織形態を特徴としており,免疫染色にて上皮系マーカーに濃染したことから膀胱Plasmacytoid Carcinomaと診断し得た.過去の報告から通常の尿路上皮癌と異なり,有転移症例に対しても抗がん剤の高い効果が得られる場合もあり,積極的な治療の必要性が示唆された.

We experienced a case of plasmacytoid urothelial carcinoma of the bladder. A 79-year-old man was referred with urinary frequency. Computed Tomography, Magnetic Resonance Imaging and ultra-sonography of the abdomen showed a diffuse and invasive mass occupying most of the bladder. Cystoscopy showed mostly non papillary tumor in the bladder, which was resected. Pathological examination of the specimen showed a diffuse monotonous cellular infiltration that invaded the lamina propria and the muscularis propria. He received radical cystectomy, and two cycles of systemic chemotherapy were performed with methotrexate, etoposide, vinblastine, and cisplatin, due to a lymphnode metastasis (pT3a, pN1, M0). He was disease free for 11 months. The tumor cells were medium-sized, round with eosinophilic cytoplasm and eccentric nuclei, producing a plasmacytoid appearance. Immunohistochemical studies were positive for epithelial markers and negative for lymphoid markers. So, we could diagnose as plasmacytoid urothelial carcinoma. This is a rare tumor. This case is the 30th case in the English literature.