Treatment with clodronate does not improve survival in patients with early or advanced breast cancer, according to the results of a meta-analysis published in the British Journal of Cancer,
The authors note that some trials have shown an association between bisphosphonates and improved overall survival and metastasis-free survival in breast cancer patients, whereas others have been negative. They therefore conducted a meta-analysis of results from 13 trials to examine the effect of oral clodronate 1,600mg daily for two or three years (versus placebo or no treatment) on five-year overall survival, bone-metastasis-free survival and nonskeletal metastasis-free survival in women with breast cancer.
Their results found no difference in overall survival, time to appearance of bone metastasis, or the occurrence of nonskeletal metastases between patients who received adjuvant clodronate treatment and those who did not, in women with early breast cancer or advanced breast cancer.
They note that potential limitations exist due to the availability, quality and heterogeneity of the published data.
For example, no assessment of any treatment with tamoxifen or aromatase inhibitor therapy was conducted among two trials, and confounding factors such as progesterone receptor status were not balanced.
The authors conclude: