[A prostatic duct carcinoma difficult to distinguish from transitional cell carcinoma: a case report].

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.