Letrozole in the extended adjuvant setting: MA.17

摘要: Relapse after completing adjuvant tamoxifen therapy is a persistent threat for women with hormone-responsive breast cancer. Third-generation aromatase inhibitors, such as letrozole, provide new option extended hormonal 5 years of tamoxifen. MA.17 was conducted to determine whether letrozole improves outcome discontinuation Postmenopausal hormone receptor-positive cancer (N = 5,187) were randomized 2.5 mg or placebo once daily 5 years. At median follow-up 30 months, significantly improved disease-free survival (DFS; P < 0.001), the primary end point, compared (hazard ratio [HR] recurrence contralateral 0.58; 95% confidence interval [CI] 0.45, 0.76] P < 0.001). Furthermore, distant DFS (HR = 0.60; CI 0.43, 0.84; P = 0.002) and, in node-positive tumors, overall (HR = 0.61; 0.38, 0.98; P = 0.04). Clinical benefits, including an advantage, also seen who crossed over from unblinding, indicating that tumors remain sensitive despite prolonged period since The efficacy and safety beyond being assessed re-randomization study, following emergence data suggesting clinical benefit correlates duration letrozole. showed extremely well-tolerated relative placebo. Letrozole should be considered all tamoxifen; results post-unblinding analysis suggest treatment periods up completion