Researchers Examine Toxicity of Breast Cancer Drugs

Photodisc/Thinkstock(NEW YORK) -- Drugs called aromatase inhibitors are used to treat breast cancer in post-menopausal women.  They work by inhibiting the production of estrogen which stimulates the growth of breast cancer cells.

A study in the Journal of the National Cancer Institute looks at why the drugs, called AIs, are associated with a reduction in breast cancer recurrence but not in improved survival.

Researchers found that, compared with Tamoxifen -- another breast cancer drug -- longer use of AIs was associated with a number of adverse toxic effects -- among them, increased heart disease and bone fractures.

The authors conclude that the toxicity of AIs over long periods of treatment may explain the lack of overall survival benefit despite a positive effect on breast cancer recurrence.

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