Maximum androgen blockade療法における低用量フルタミドの有用性

Abstract

低用量フルタミド投与(250mg/日/分2)による肝障害発現率の抑制及び臨床的効果の同等性について, 従来の常用量投与群(375mg/日/分3)とレトロスペクティブに比較検討した.血清PSA値に対する効果に差はなく, 又, AST・ALTを指標とした肝機能障害の発現率においても差は認めなかった.しかし, 肝障害を原因とする投与中止例は低用量群(2.9%)で有意に少なかった.低用量投与は常用量投与に比べて肝障害による治療脱落が少なく, 長期予後の改善を期待できる方法であると考えられた

To prevent treatment withdrawal due to flutamide-induced liver dysfunction, we performed maximum androgen blockade (MAB) therapy by combining a luteinizing hormone-releasing hormone agonist or orchiectomy with low-dose flutamide (125 mg x 2/day) in patients with prostate cancer. In this study, the efficacy, adverse effects such as hepatotoxicity, and compliance were compared retrospectively between 35 patients who received low-dose flutamide therapy (1995-1999) and 27 patients who received flutamide at its ordinary dose (125 mg x 3/day). No significant difference was observed in the response rate (> or = PR) as determined from the prostate-specific antigen parameter (p = 0.6211) or the incidence of hepatotoxicity based on the aspartate aminotransferase and alanine aminotransferase levels. However, flutamide withdrawal due to liver dysfunction was less frequent in the low-dose group (2.9%) than in the ordinary dose group (18.5%) (p = 0.0386). MAB therapy using low-dose flutamide is expected to prevent the reduction in the compliance due to side effects and to improve the long-term prognosis in patients with prostate cancer, who are mostly elderly individuals.