Zoledronic Acid Therapy Improves Subgroup Breast Cancer Survival

Zoledronic acid (ZOL) therapy administered with chemotherapy appears to improve disease-free survival and overall survival in a subset of breast cancer patients with oestrogen receptor negative tumors, according to researchers from the John Cochran VAMC and the Washington University School of Medicine, both in St. Louis.

The study, published recently in the British Journal of Cancer, notes that women with resectable Stage II/III breast cancer have a high risk of recurrent disease, despite neoadjuvant/adjuvant chemotherapy. Recent data suggests that ZOL therapy concurrent with adjuvant treatments could improve cancer-related outcomes in those patients, the authors wrote. ¹

Researchers evaluated disease-free survival and overall survival in 119 women with Stage II/III breast cancer divided into two groups. One received 4 mg of ZOL therapy every three weeks for a year, starting with the first chemotherapy cycle. The control group did not receive ZOL therapy.

No significant difference in recurrence or survival was noted between the study group and the control at 61.9 months median follow-up, but time until recurrence and death rates differed significantly between subgroups defined by oestrogen-receptor status.

Hazard ratios for disease recurrence and death were significantly less among patients with oestrogen receptor negative tumors who received ZOL therapy, as opposed to those who had not received the therapy (DFS: HR=0.361, 95% confidence interval (CI) 0.148, 0.880; OS: HR=0.375, 95% CI 0.143, 0.985)

The authors caution that, because of researcher limitations, the study should be considered as “hypothesis-generating” and not conclusive.

1: Aft RL, Naughton M, Trinkaus K, Weilbaecher K. Effect of (Neo)adjuvant
zoledronic acid on disease-free and overall survival in clinical stage II/III
breast cancer. Br J Cancer. 2012 May 22. doi: 10.1038/bjc.2012.210. [Epub ahead
of print] PubMed PMID: 22617128.