前立腺偶発癌の臨床的検討

Abstract

前立腺肥大症の診断で前立腺被膜下摘除術あるいは経尿道的前立腺切除術(TUR-P)を施行した1, 388例と, 膀胱癌で膀胱前立腺全摘除術を施行した156例, 計1, 554例の中で組織学的に偶発癌と診断された28例を対象とした.1)偶発癌の頻度は1, 554例中28例1.8%で, A1 9例, A2 19例とほぼ1:2の比となった.分化度別でみると高分化癌は28例中18例, 中分化癌は9例, 低分化癌は1例であった.2) 5年生存はA1 7例, A2 15例.10年生存はA1 7例, A2 7例であり統計学的有意差は認めず, 癌死症例はなかった.3)偶発癌より臨床癌に移行した症例は28例中6例あり, A1 1例, A2 5例であった.偶発癌発見時の治療の点から見ると, 6例中5例が無治療のまま経過観察していた症例であった

At the Center for Adult Diseases, Osaka, between 1961 and 1987, 28 cases (1.8%) of incidental prostatic adenocarcinoma were detected by transurethral or subcapsular prostatectomy for clinically benign prostatic hypertrophy (1388 cases) and cysto-prostatectomy for urinary bladder carcinoma (156). Nine (32%) and 19 (68%) cases were in stages A1 and A2, respectively. Of the 19 A2 cases, 9 were well, 9 were moderately and 1 was poorly differentiated adenocarcinoma. Five of the A2 and 1 of the A1 progressed into clinical carcinoma, but none of these patients died of the cancer. Four of these 5 A2 patients had received no treatment postoperatively and one received castration. The intervals from diagnosis to progression ranged from 11 to 78 months. The survival rates at 5 and 10 years with A1 were 75% and 75%, and those with A2 were 80% and 37%. We conclude that the patients in stage A2 should be treated because stage A2 tumors, especially those with no treatment, progress at a higher frequency than stage A1 tumors.