Clinical Oncology News - Zoledronic Acid Debate in Breast Cancer Continues

Clinical Oncology News - Zoledronic Acid Debate in Breast Cancer Continues

San Antonio—Long-term results of the ABCSG-12 trial and subanalyses of two recently presented Phase III trials provide further evidence that bisphosphonates can improve survival in breast cancer patients with low estrogen levels. The results of the studies, presented at the recent San Antonio Breast Cancer Symposium (SABCS), have convinced some doctors of the low estrogen hypothesis, but for others the water is still very murky.....


Weighing the Evidence
In recent years, some oncologists have been prescribing bisphosphonates off-label to treat breast cancer, and the new studies may sway more doctors to do so.
“The anticancer effects of adjuvant zoledronic acid are now well established in endocrine-responsive patients,” said Dr. Gnant.
Dr. Paterson added that “inhibition of osteoclast function with bisphosphonates has an effect on cancer growth in older women, and little effect in premenopausal women.”
For other doctors, however, the jury is still out. “Subanalyses are suspect,” said Dr. Vogl. “This is interesting, but we need to study it some more. But if they study it some more, Novartis will have lost its patent protection by the time that study comes out. Novartis has some interest in it [being approved] now.”

Dr. Paterson is a consultant for GlaxoSmithKline, Amgen, Roche and Nicomed and has received a grant for a clinical trial involving denosumab. Dr. Gnant disclosed relationships with AstraZeneca, Novartis, Pfizer, Sanofi, Roche, Schering and Amgen. Dr. Möbus disclosed relationships with Amgen, Novartis and Roche. Dr. de Boer disclosed a relationship with Novartis. Drs. Ingle and Dr. Vogl have no relevant disclosures.