移行上皮癌と鑑別困難であった前立腺導管癌の1例

Abstract

77歳男.糖尿病・パーキンソン病の既往がある.4ヵ月ほど前から排尿困難を自覚し肉眼的血尿を認めるようになり来院, 腹部エコー所見で膀胱頸部より突出する腫瘤を認め精査加療目的で入院となった.入院時, 中等度嚥下困難・両下肢筋力低下・上肢振戦および前立腺の鶏卵大腫大を認め, 血液検査では軽度貧血とPSA値は1130ng/mlと高値を示し, 尿細胞診はclass IIで陰性であった.骨盤部造影CT・MRI所見で膀胱内に突出する前立腺に連続する腫瘤を認め, 骨シンチ検査では多発性の転移を認めた.膀胱鏡所見では膀胱頸部3時～7時方向にかけて腫瘤を認め, 生検の結果尿路上皮由来の移行上皮癌, G2と診断された.本症例は根治手術適応ではないが, 膀胱タンポナーデを繰り返すため膀胱前立腺全摘除術+尿管皮膚瘻造設術を施行した.摘出標本の病理組織学的所見から腺癌と導管癌の両方を含む前立腺癌と診断, 術後内分泌療法を施行したが奏効せず, 誤嚥性肺炎の併発により術後2ヵ月半で死亡した

A 77-year-old male with a complaint of dysuria and gross hematuria for 3 months visited our hospital. Abdominal ultrasonography, computed tomographic scan and magnetic resonance imaging revealed a prominent tumor from the bladder neck. Serum prostate specific antigen (PSA) level was high (1, 130 ng/ml) suggesting prostate cancer, but transitional cell carcinoma (TCC) was detected by transurethral biopsy. Bone scintigraphy revealed multiple bone metastasis. Since gross hematuria requiring bladder tamponade continued, simple cystoprostatectomy and cutaneous ureterostomy were performed. Pathological findings showed prostatic acinar carcinoma and prostatic duct carcinoma mimicking TCC, and PSA immunohistochemically weak positive. The final diagnosis was prostate cancer consisting of acinar and ductal component. Adjuvant hormonal therapy was performed, but was ineffective. The patient died 2.5 months after operation. We reviewed and discussed 66 cases of prostatic duct carcinoma, including our case, in the Japanese literature.