As the second most common cancer in men worldwide, prostate cancer accounts for over 200,000 new cases and 30,000 deaths annually, reports the National Cancer Institute. Although normal growth and function of the prostate requires androgens, two independent large population-based studies found that the risk of prostate cancer increases with higher levels of blood androgens.
Testosterone
The two most common blood androgens include testosterone and the more potent steroid, dihydrotestosterone. According to MedlinePlus, normal blood testosterone ranges from 300 to 1,200 nanograms per deciliter in adult males. Due to lab variability, specific blood testosterone levels need to be discussed with your doctor within the context of the lab's controls.
Testosterone and Prostate Cancer
According to the American Institute for Cancer Research Expert Report, two cases reported that men who used androgen steroids for recreational use or as medical treatment later developed prostate cancer. Huggins and Hodges first reported in 1941 that reducing testosterone levels reduced advanced prostate cancer in patients. Ross and colleagues reported that Japanese males have lower circulating levels of some androgens compared to Westerners. Additionally, Japanese males account for fewer cases of prostate cancer compared to Caucasians.
Pharmacological Agents and Diet
Two drugs target androgen production in your body. Finasteride and Dutasteride reduce total blood androgen levels. Commonly used to treat an enlarged prostate, doctors also use these drugs to reduce your risk of developing prostate cancer. In a phase II randomized-controlled trial by Kumar et al., serum free testosterone decreased with lycopene supplementation in men with clinically localized prostate cancer. Diets containing soy, lower fat, flaxseed and phytoestrogens also may reduce serum testosterone in prostate cancer patients. Further research will determine the association between dietary components and testosterone levels.
Ratio of Testosterone to Estrogen
Testosterone levels decrease with age in men while blood estrogens remain relatively constant. African-American men are exposed to higher circulating estrogen levels in utero compared to Caucasian men. African-American men also account for more cases of prostate cancer than Caucasian men. Dr. Ho hypothesizes that this estrogen exposure increases prostate cancer risk later in life. Overall, the effects of estrogens in the prostate are complex and warrant further investigation.
References
- "Journal of the National Cancer Institute"; Prospective Study of Sex Hormone Levels and Risk of Prostate Cancer; PH Gann, CH Hennekens, J Ma, et al.; Aug. 1996
- "Journal of Clinical Oncology"; Hormonal Predictors of Prostate Cancer: a Meta-Analysis; T Shaneyfelt, R Husein, G Bubley, et al.; Feb. 2000
- "Journal of Urology"; The Effect of Castration, of Estrogen and of Androgen Injection on Serum Phosphatases in Metastatic Carcinoma of the Prostate; C Huggins; CV Hodges; July 2002
- "Clinical Medical Urology"; Results of a Randomized Clinical Trial of the Action of Several Doses of Lycopene in Localized Prostate Cancer: Administration Prior to Radical Prostatectomy; NB Kumar, K Besterman-Dahan, L Kang, et al.; Apr. 2008
- "Lancet"; 5-Alpha-Reductase Activity and Risk of Prostate Cancer Among Japanese and US White and Black Males; RK Ross, L Berstein, RA Lobo, et al.; Apr. 1992
- "Journal of Cell Biochemistry"; Estrogens and Anti-Estrogens: Key Mediators of Prostate Carcinogenesis and New Therapeutic Candidates; SM Ho; Feb. 2004
