[Prostatic cancer with cystic formation: a case report]

An 82-year-old man presented with a huge hypogastric tumor. A pelvic computed tomographic scan and magnetic resonance imaging revealed a multiple cystic mass 14 x 10 x 15 cm in diameter. The prostate specific antigen (PSA) value was elevated to 903 ng/ml. Histological examination of the needle biopsy specimens of the prostate revealed moderately differentiated adenocarcinoma. Bone scintigraphy showed a hot area in part of the costa. No other abnormalities were found. The tumor origin was suspected to be the prostate, but the possibility that it was another organ could not be denied completely since the tumor was located in the anterior portion above the bladder. Treatment with luteinizing hormone-releasing hormone agonist and diethylstilbestrol was initiated considering the patient's age. The PSA value returned to normal and the tumor size was reduced markedly after 28 weeks of therapy. Thirty-seven case of prostatic cancer with cystic formation in the Japanese literature are reviewed.