[Treatment of advanced metastatic breast cancer with exemestane, a multicenter randomized controlled study of 195...

To observe the efficacy of exemestane for postmenopausal advanced metastatic breast cancer, and to assess its side effects.

A randomized, double-blind, and parallel controlled study was conducted among 195 patients with postmenopausal advanced metastatic breast cancer from December 2001 to June 2002. Except for the 4 cases who were lost to follow-up, the remaining 191 patients were divided into two groups: study group (n = 96, treated with exemestane capsule 25 mg and one model tablet of letrozole orally q.d. for 8 weeks), and control group (n = 95, treated with letrozole 2.5 mg and one model capsule of exemestane orally q.d. for 8 weeks). Physical examination, roentgenography and CT were conducted to observe the outcome of the tumor and the level of estrogen was tested 2 weeks before and 4 and 8 weeks after the beginning of treatment.

The effective rate was 44.8% in the study group and 45.3% in the control group (P = 0.971). The level of estradiol was 5.17 +/- 6.68 x 10(4) pg/L and 4.19 +/- 3.06 x 10(4) pg/L in the study group and control group respectively; and was 3.08 +/- 2.80 x 10(4) pg/L and 2.76 +/- 1.98 x 10(4) pg/L in the study group and control group respectively 8 weeks after the beginning of treatment, both decreased by 43.7% in comparison with those before treatment (both P < 0.001), however, there was no significant difference between the study group and control group (P = 0.141). The side effects of exemestane included thirst, giddiness, and nausea.

An effective hormonal medicine, exemestane has good therapeutic efficacy in postmenopausal advanced metastatic breast cancer with only mild side effects.