Because a total lack of estrogen is extremely harmful to existing bones and bone growth, patients are usually prescribed an osteoporosis drug in tandem with the aromatase inhibitor: I was put on a weekly dose of Fosamax, and I have now taken both drugs for almost 2 years.
On Thursday, Dec. 10th, the results of a new observational study involving more than 150,000 post-menopausal women were announced at the San Antonio Breast Cancer Symposium: women taking Fosamax, or other biphosphonate osteoporosis drugs (Boniva, Actonel) had 32% fewer cases of invasive breast cancer than women who were not taking these drugs. This is a significant finding, both for the percentage of cancers avoided, and because the biphosphonates are now seen to benefit patients in an entirely different manner than for which they were originally intended.
A previous study had already established that breast cancer patients who were given biphosphonate osteoporosis medication (Zometa) intravenously every 6 months developed fewer new contralateral breast cancers in the unaffected breast.
So, treatment with osteoporosis biphosphonate drugs appears both to prevent cancer recurrence in breast cancer patients, and also to reduce initial occurrences of breast cancer in healthy postmenopausal women. The drugs are also seen to prevent breast cancers from spreading to the bones by creating unfavorable conditions for tumor growth in bone tissues.
The chief oncologist behind the latest study stated that the biphosphonates also interfere with growth of blood vessels to tumors, and they simultaneously stimulate immune cells whose role is to seek out and destroy tumor cells.
If this can all be proven, there will be other very good reasons for post-menopausal women to take osteoporosis drugs. Right now, I'm very glad to hear that I might also be reducing my chance of developing a new cancer via both the Arimidex and Fosamax. Hopeful news!