Abrams J S, Gutheil J, Aisner J
Department of Medicine, University of Maryland Cancer Center, Baltimore 21201.
Oncology. 1992;49 Suppl 2:12-7. doi: 10.1159/000227121.
Empiric clinical trials have revealed new mechanisms by which hormonal therapies may exert their antitumor effects. Initial studies using escalated doses of agents like toremifene and megestrol acetate have yielded interesting results, showing responses in hormone-receptor-negative patients and in patients progressing after standard doses, respectively. A trial by Cancer and Leukemia Group B randomizing patients with advanced breast cancer to standard-dose (160 mg) megestrol acetate or to 5 or 10 times the standard dose (800 and 1,600 mg) has completed accrual. It is hoped that these results will provide a definitive answer to the dose-response issue for breast cancer. However, regardless of this trial's ultimate outcome, higher doses of megestrol acetate have demonstrated important new effects on appetite stimulation and weight gain; ongoing laboratory research promises potential roles for megestrol acetate in the reversal of chemotherapeutic drug-induced tumor resistance.
经验性临床试验揭示了激素疗法发挥抗肿瘤作用的新机制。最初使用递增剂量的药物（如托瑞米芬和醋酸甲地孕酮）进行的研究取得了有趣的结果，分别显示出对激素受体阴性患者以及在接受标准剂量治疗后病情进展的患者有反应。癌症与白血病B组进行的一项试验将晚期乳腺癌患者随机分为接受标准剂量（160毫克）醋酸甲地孕酮组或标准剂量的5倍或10倍（800毫克和1600毫克）组，该试验已完成病例招募。希望这些结果能为乳腺癌的剂量反应问题提供明确答案。然而，无论该试验的最终结果如何，更高剂量的醋酸甲地孕酮已显示出对刺激食欲和体重增加的重要新作用；正在进行的实验室研究有望揭示醋酸甲地孕酮在逆转化疗药物诱导的肿瘤耐药性方面的潜在作用。
