And, for postmenopausal women, immediate ZOL therapy reduces risk of disease-free survival events
WEDNESDAY, Dec. 7 (HealthDay News) -- In the long-term, adjuvant zoledronic acid (ZOL) is associated with a significant reduction in disease-free survival (DFS) events and death in premenopausal women with endocrine-receptor positive early-stage breast cancer; and for postmenopausal women with hormone receptor-positive early breast cancer, immediate treatment with ZOL is associated with a reduced risk of DFS events, according to two studies presented at the annual San Antonio Breast Cancer Symposium, held from Dec. 6 to 10.
Michael Gnant, M.D., from the Medical University of Vienna in Austria, and colleagues investigated the long-term effect of adjuvant ZOL for premenopausal patients with endocrine-responsive early stage breast cancer. At a median follow-up of 76 months, compared with patients not receiving ZOL, those patients receiving ZOL treatment had a significant reduction in the risk of DFS events (hazard ratio [HR], 0.73) and death (HR, 0.59).
Richard de Boer, M.D., from the Royal Melbourne Hospital in Australia, and colleagues compared the benefit of immediate (IMZOL) or delayed (DZOL) treatment with ZOL, for 1,065 postmenopausal women with hormone receptor-positive early breast cancer. At 60-months of follow-up, there was a significant reduction in the risk of a DFS event with IMZOL versus DZOL (HR, 0.66). For women who were postmenopausal for more than five years, or were older than 60 at the study entry, IMZOL was associated with significantly improved DFS and prolonged overall survival versus DZOL (HR, 0.63 and 0.50, respectively).
"Long-term follow-up in [the] Zometa-Femara Adjuvant Synergy Trial confirms the overall survival benefits of adding ZOL (4 mg q6mo) to adjuvant letrozole therapy for early breast cancer," de Boer and colleagues write.
Press Release - Gnant
Press Release - de Boer