前立腺小細胞癌の3例 : 本邦報告例による予後解析

Abstract

前立腺小細胞癌3例について報告した。症例1(29歳男)。1998年1月に右側腹部痛で受診し、腹部CTで骨盤内腫瘍、両側水腎症を認めた。両側尿管ステント留置後腹部CTで小骨盤腔を占拠し径7cm大の腫瘍と両側骨盤リンパ節腫大も認めた。生検を行いNSE、NCAM染色で前立腺原発小細胞癌と確定した。治療開始から17ヵ月後癌死した。症例2(65歳男)。2004年4月に尿閉で受診し前立腺肥大症を疑われた。尿道カテーテル留置10日後乏尿と浮腫が現れ、両側水腎症及び急性腎不全と診断された。直腸診で石様硬の前立腺に触れ、経皮的腎瘻造設術を行い腎機能の改善後CDDP+VP-16を投与した。肺転移は消失したが16ヵ月後癌死した。症例3(73歳男)。2004年9月に前立腺生検で低分化腺癌と診断され、MAB療法開始後、10月に高度全身倦怠感が現れた。生化学検査で異常値を認め、腹部CT/MRIでは骨盤腔を占拠し膀胱直腸に湿潤する巨大な腫瘍と骨盤リンパ節転移を認め、15ヵ月目に癌死した。

Small cell carcinoma (SCC) originating from the prostate is rare. We report three cases of SCC of the prostate. Case 1: A 29-year-old man with large pelvic mass and pelvic lymph node metastases was diagnosed as having pure SCC of the prostate. Chemo-radiotherapy resulted in a great reduction of the tumor volume. However, the disease recurred immediately, and he died of disease 17 months after diagnosis. Case 2: A 65-year-old man presented with pure prostatic SCC with lung metastases. Although cystoprostatectomy combined with pre- and post-operative chemotherapy ended with no evidence of disease, he died after 16 months because of multiple metastases and local recurrence. Case 3: A 73-year-old man was diagnosed as having SCC and poorly differentiated adenocarcinoma of the prostate simultaneously. Chemo-endocrine therapy and pelvic irradiation were performed, achieving partial remission. However, he developed multiple distant metastases, and died of disease 15 months after diagnosis. We reviewed 82 cases previously reported in Japan. Patient's ages ranged from 24 to 86 years (mean 68.7 years). Many patients had lymph node or distant metastases (stage D, 73%). Thirty-seven (45%) were pure SCCs and 45 (55%) were associated with adenocarcinoma. The prognosis after the recognition of SCC is very poor, and the 1- and 2-year survival rates were 27% and 10%, respectively. Survival did not differ in patients with pure SCC or mixed glandular and small cell carcinoma. Higher elevation of pretreatment serum NSE value was associated with the poor prognosis.