巨大水腎症に合併したベリニ管癌の1例

Abstract

56歳男.肉眼的血尿を主訴とした.初診時, 腹部に圧痛のない緊満状の巨大腫瘤を触知し, intravenous pyelographyにて右腎は描出不能, 左腎に軽度の腎盂拡張および代償性肥大を認めた.CT, MRIにて右の巨大水腎症を, 経皮的直接腎盂造影にて巨大な腎外腎盂を認め, 穿刺腎盂尿細胞診classVより巨大水腎症を伴う腎盂あるいは尿管腫瘍として右腎尿管全摘除術を施行し, 腎盂穿刺にて1010mlの内溶液を吸引した.病理組織学的所見では不規則な管腔形成性の浸潤性腺癌像や集合管類似構造を認め, 免疫染色ではUEA-I, EMAに陽性, 高分子重量サイトケラチン, ビメンチンに一部陽性, サイトケラチン20陰性より巨大水腎症を伴うベリニ管癌と診断した.術後は良好に経過したが, 多発性骨転移をきたし癌死された.自験例では画像上, 非典型的所見を示し, 血尿等の症状を有する巨大水腎症では悪性腫瘍も念頭に置いて診断・治療を行うべきであると考えられた

We report a case of Bellini duct carcinoma with giant hydronephrosis. A 56-year-old man was referred with the chief complaint of gross hematuria. The intravenous pyelography showed a huge right renal contour and non-functioning kidney. The abdominal computed tomographic scan and magnetic resonance imaging demonstrated giant hydronephrosis. Percutaneous urinary cytology obtained in the direct pyelography was class V. Right total nephro-ureterectomy was performed. Punctured fluid volume was 1, 010 ml during the operation. Histological and immunohistochemical analysis revealed the collecting duct carcinoma of the kidney. Three months later, multiple bone metastases had appeared. He was treated by the combination chemotherapy of gemcitabine and paclitaxel, but lung and liver metastases developed. The patient died of cancer 12 months later. This case was considered to be Bellini's duct carcinoma as its features had poor prognosis and image findings infiltrating from medulla to cortex with the total enlargement of the kidney. To our knowledge there has been no case found like these atypical imaging findings.