Aside from skin cancer, prostate cancer is the most common malignancy in American men, and it is the second leading cause of cancer death in this group, according to a January 2011 article published in the "Journal of Carcinogenesis," which goes on to note that you have a 1 in 6 chance of developing prostate cancer sometime during your lifetime if you are a male. Many prostate cancers are slow-growing and never spread beyond your prostate gland, but those that do often move to your bones. Zoledronic acid is used to treat aggressive prostate cancers.
Skeletal Events
Once prostate cancer has metastasized, or spread, to your bones, which is common, treatment is primarily aimed at reducing complications related to the growth of tumor cells in your skeleton. Bone involvement by any tumor typically causes severe pain, and fractures occurring at sites of tumor invasion lead to additional pain and disability. Dangerous elevations of blood calcium may also arise from bony metastasis. Zoledronic acid helps alleviate many of these "skeletal events."
Preserving Bone Mass
Zoledronic acid belongs to a group of drugs called bisphosphonates, which includes Fosamax, Boniva, Actonel and similar agents. A more familiar and conventional use for these medications is in the treatment of osteoporosis. Prostate cancer treatment often involves the use of medications that antagonize testosterone and other androgen hormones, which leads to accelerated bone loss in prostate cancer patients. As reported in the October 2007 issue of "Current Opinion in Supportive and Palliative Care," one of zoledronic acid's primary uses in prostate cancer is to prevent osteoporosis caused by your treatment.
Delaying Cancer Progression
The study noted in the January 2011 issue of the "Journal of Carcinogenesis" demonstrates that zoledronic acid exerts direct effects on the cells of highly aggressive prostate cancers. By decreasing the rate of division and increasing the rate of death in prostate cancer cells, zoledronic acid actually inhibits bony metastasis of aggressive tumors. This explains observations of slowed tumor growth in prostate cancer patients who are receiving zoledronic acid, and it may have implications for treating cancers that are determined to be aggressive on initial prostate biopsy, before they have spread to your bones.
Considerations
Prostate cancer is common among men, with your chances for developing this disease increasing as you age. According to "The Merck Manual of Diagnosis and Therapy," autopsies reveal that 15 to 60 percent of men aged 60 to 90 have prostate cancer at the time of their deaths. However, only a fraction of these men have metastatic prostate cancer, indicating the generally slow-moving nature of most prostate tumors. For those prostate cancers that do spread beyond the prostate -- and possibly for aggressive tumors that have not yet spread -- zoledronic acid is a useful addition to therapy.
References
- "Journal of Carcinogenesis"; Zoledronic Acid Directly Suppresses Cell Proliferation and Induces Apoptosis in Highly Tumorigenic Prostate and Breast Cancers; H. Almubarak, et al.; January 2011
- "Current Opinion in Supportive and Palliative Care"; Preservation of Bone Health in Prostate Cancer; J.B. Lattouf, F. Saad; October 2007
- "The Merck Manual of Diagnosis and Therapy, 18th Edition: Prostate Cancer"; Mark H. Beers, M.D., Editor-in-Chief; 2006
