Activity of megestrol acetate in postmenopausal women with advanced breast cancer after nonsteroidal aromatase inhibitor failure: a phase II trial

Results: Forty-eight patients were enrolled. The CBR was 40% [95% confidence interval (CI) 25% to 55%], and the median duration of clinical benefit was 10.0 (95% CI 8.0–14.2) months. The median PFS was 3.9 (95% CI 3.0–4.8) months. The most common grade 3 adverse events were anemia (2%), dyspnea (2%), fatigue (2%), musculoskeletal pain (4%), deep vein thrombosis (10%), and weight gain (2%). Conclusions: This is the first study to prospectively evaluate the efficacy and safety of MA in postmenopausal women with hormone-sensitive disease progressing on a NSAI. MA has demonstrated activity and acceptable tolerability in this setting, and therefore remains a reasonable treatment option in a cost-sensitive environment. These results also provide the background for further evaluation of progestins in the treatment of breast cancer. Clinical Trials: local trial number, related to the approval by the IRB: CEP 108/06