Extended adjuvant treatment with exemestane an excellent choice

Extended adjuvant treatment with exemestane [Aromasin] after completion of 5 years' tamoxifen therapy improves disease-free and relapse-free survival, according to data from the NSABP* B33 trial presented at the 29th Annual San Antonio Breast Cancer Symposium (SABCS) [San Antonio, Texas, US; December 2006]. The NSABP B33 trial was a randomised, double-blind, placebo-controlled trial that evaluated the efficacy of exemestane as extended adjuvant therapy in patients with early stage breast cancer who were disease-free after 5 years of tamoxifen therapy. Accrual to the trial was prematurely discontinued in October 2003 after results of the NCIC** MA.17 trial demonstrated a benefit for letrozole [Femara] in the same treatment setting; at that time, placebo recipients were offered active treatment with exemestane. Despite the confounding effects of crossover, a significantly higher proportion of patients randomised to receive exemestane than placebo were relapse-free after a median follow-up duration of 30 months; there was also a trend towards significance for an advantage for exemestane with respect to disease-free survival at the same time point.