Oral estramustine phosphate and oral etoposide for the treatment of hormone-refractory prostate cancer

Abstract

A total of 42 patients with hormone-refractory prostate cancer received E-E therapy. Oral estramustine phosphate (EMP) was administered twice daily for a total daily dose of 560 mg every day and oral etoposide (E-E therapy, 50 mg/body/day) was given on days 1-21 and stopped on days 22-35. Treatment was continued until the disease progression was confirmed radiographically or PSA had increased from base line of at least 25%. The median follow-up period after E-E therapy was 77.4 months (range : 12.5 to 122.3). Nineteen patients (43%) achieved a PSA decrease of 50% or greater. The median survival time of the patients who had a decrease of 50% or greater in the PSA value (PSA responder) was 29.3 months and the patients who did not (PSA non-responder) was 14.1 months (p = 0.01). There were no significant differences between PSA responders and non-responders when taking into account variables. Excluding those patients with only PSA elevation, the survival time was 14.9 months with no significant difference between PSA responders and non-responders. The toxicities (grade 3 or more) were identified as anemia, leukocytopenia thrombocytopenia, cardiovascular events, and gastrointestinal and hepatic disorders, which occurred in 0, 5, 2, 2, 14, and 2% of the patients, respectively. E-E therapy was considered to be an active oral regimen and well-tolerated for outpatients with hormone-refractory prostate cancer in Japanese patients.

【目的】日本人における再燃前立腺癌に対する経口リン酸エストラムスチン(EMP), エトポシド(VP-16)併用療法(EE療法)の効果および副作用について検討した。【方法】1995年以降, EE療法が施行された再燃前立腺癌患者42例が対象。EMP:560mgを連日投与, VP-16:50mgを21日投与し14日休薬を1サイクルとした。PSAが50%以上低下したものをresponderとし, 治療は画像上の増悪またはPSAが基準値より25%を認めるまで継続した。【結果】観察期間は77.4ヵ月。19例がresponderであった。42例の生存中央値は20.5ヵ月でありresponderでは29.3ヵ月, non-responderで14.1ヵ月(p=0.008)であった。群間でresponseに寄与する因子は存在しなかった。Grade 3以上の副作用は白血球減少(5%)が2例, 血小板減少(2%)が1例, 悪心が6例(14%), 肝機能障害が1例(2%), 深部静脈血栓症(2%)が1例に認めた。【結語】EE療法は抗腫瘍効果もあり, 副作用も容認でき日本人にも施行可能であった。(著者抄録)