化学療法併用放射線療法が有効であった前立腺小細胞癌の1例

Abstract

49歳男.頻尿及び尿線の減弱が生じたため受診した.前立腺肥大症の診断でセルニルトン及び塩酸タムスロシンを服薬したが, 症状の改善は認められなかった.前立腺肥大症と診断し経尿道的前立腺切除術を施行した.免疫組織化学染色等により純粋な前立腺小細胞癌と診断した.シスプラチンとエトボシドを使用した全身化学療法と骨盤腔への放射線療法の併用療法を開始した.左精巣上体炎が生じたため, 抗生剤投与し, 精管結紮術を施行した.治療終了後1ヵ月に治療効果判定をした.治療前に異常高値を示したProGRPは正常化し, CTで前立腺は断面積で50%縮小した.頭部CT, 胸部CT, 胸写, 腹部CT及び骨シンチグラフィーで転移は認められなかった.治療終了後1ヵ月の時点では臨床的には完全緩解が得られたと判断した

A 49-year-old man complained of dysuria and pollakisuria. The prostate was enlarged, and the serum level of prostate specific antigen was within the normal range. Under the diagnosis of benign prostatic hypertrophy, transurethral resection of the prostate was performed. Unexpectedly, histopathological examination of the resected tissues revealed pure small cell carcinoma. The serum level of progastrin-releasing peptide (ProGRP) was slightly elevated. The cancer was clinically diagnosed as stage C. Pelvic radiotherapy combined with chemotherapy using cisplatin (CDDP) and etoposide (VP-16) was started according to the treatment for limited small cell cancer of the lung. After one month, the serum level of ProGRP decreased to the normal range. After four months, the prostate was reduced in size without any findings of metastases on computed tomography, and prostate biopsy revealed no viable cancer cells.