According to the National Cancer Institute, prostate cancer is the second leading cause of cancer death among U.S. men, with nearly 31,000 men succumbing to this disease each year. It is believed to affect as many as 40 percent of men over age 50, and the incidence rises with age. Most patients are older, with 72 being the median age of diagnosis. If a man has a family history of prostate cancer, this is an increased risk, particularly if the relative was diagnosed prior to age 50. African Americans are also at higher risk for this cancer.
In its early stages and as the disease progresses, prostate cancer symptoms usually mirror those of BPH. Typically, the diagnosis is made when suspicious tissue is discovered during a digital rectal exam, prompting the healthcare practitioner to order a PSA test. When these results indicate the likelihood of cancer, a biopsy is performed.
While the cause of prostate cancer remains unknown, hormonal changes are strongly implicated. Lowering testosterone levels and/or manipulating its metabolism have proven to be important tools for treating existing prostate cancer. Thus, treatments for prostate cancer include a range of hormone therapies, often referred to as “androgen blockade.”
As its name implies, androgen blockade is designed to block one or more of the androgens (male hormones). The three organs shown in the figure produce these hormones. The testicles produce testosterone— by far the most plentiful male hormone. The adrenal glands secrete a small amount of several hormones known collectively as the “adrenal androgens” and the prostate produces DHT.
Other treatments for prostate cancer include surgery to remove the prostate, radiation, and chemotherapy. The options offered to any patient will vary depending on individual factors, such as their overall health and the aggressiveness of the cancer. Prostate cancer is typically very slow-growing (although this is not always the case). For older men with less aggressive tumors and men who are already in poor health, healthcare practitioners may simply advise “watchful waiting.”
Holistic practitioners often incorporate nutritional interventions to help thwart cancer. For example, Dr. Katz recommends that prostate cancer patients change their diets to reduce two factors that may feed prostate cancer: oxidation and inflammation. According to Katz, cancerous prostate tissue has higher measurements of oxidation than noncancerous tissue. Eating foods rich in antioxidants, such as fruits and vegetables, can help combat oxidation.
Oxidative stress goes hand in hand with inflammation, says Dr. Katz. He states that “some of the best minds in urological research are making a compelling case that chronic inflammation is a precursor of prostate cancer.” Dr. Katz recommends using anti-inflammatory herbs or supplements as a precautionary measure. Such herbs include holy basil, ginger, tumeric, green tea, oregano, rosemary, and several traditional Chinese herbs.
Testosterone Therapy and Prostate Cancer Risk
Numerous studies have established that severely limiting testosterone can cause prostate cancer to shrink, at least temporarily. From this fact grew the corresponding belief that raising testosterone levels would promote the growth of prostate cancer. A review of the medical literature performed by Dr. Ernani L. Rhoden and Dr. Abraham Morgentaler (published in the January 2004 issue of The New England Journal of Medicine) found no evidence that testosterone treatment causes prostate cancer, or that men with higher testosterone levels have higher rates of prostate cancer. In fact, they note that prostate cancer becomes more prevalent exactly at the time in a man’s life when testosterone levels decline. Testosterone therapy also did not consistently worsen the urinary symptoms experienced by men with prostate enlargement, say the authors. “The impact of testosterone therapy on benign prostate growth appears to be mild,” writes Dr. Rhoden, “and rarely of clinical significance.”
Another study in 2002 indicates that testosterone therapy may even benefit prostate health. The authors say 187 of 207 men with low testosterone levels who received testosterone therapy realized improvement in every parameter measured: their prostate glands all decreased in size, their PSA numbers went lower, and urinary symptoms such as frequency and urgency all improved.
When seeking to understand the effects of testosterone levels on the prostate gland, it is important to understand how the body metabolizes (breaks down) hormones. The key organ in this metabolism is the liver, which acts as a hormone processor. When the liver is unable to process hormones as quickly or effectively as it should, a hormone imbalance can result.
Estrogens, in particular, are slowly metabolized by the liver. For this reason, it is thought that improving estrogen metabolism may help improve hormone balance in older men.
Cruciferous vegetables, such as broccoli and cabbage, have been identified as helpful in maintaining balanced estrogen metabolites. When your body digests these vegetables, it produces a phytochemical called Indole-3-carbinol (I3C). Some studies show that it can inhibit the growth of prostate cancer cells.
Food supplements can have both positive and negative effects on estrogen metabolism, notes Dr. Shippen, who explains that grapefruit tends to inhibit the liver’s breakdown of estrogens, while cruciferous vegetables, such as broccoli and cauliflower, stimulate it. Zinc is believed to be especially helpful because it inhibits aromatase, the enzyme used by testosterone to create estrogens. “Many men will restore a proper balance of testosterone to estrogen purely through the use of zinc,” says Dr. Shippen.
A vicious cycle can begin for a middle-aged man struggling to achieve and maintain hormone balance, Dr. Shippen explains. A declining testosterone level “predisposes him to weight gain. Weight gain increases his estrogen level and estrogen stimulates SHBG [sex hormone-binding globulin, a protein in the blood that binds testosterone] … crippling the effectiveness of the hormone, which may cause more weight gain, which increases estrogen and so on.”
In addition, alcohol use can lower the liver’s ability to properly eliminate estrogens from the body, Dr. Shippen adds, while age and zinc deficiencies may increase aromatase, causing more of a man’s testosterone to be turned into estrogens, further stimulating SHBG, which repeats the cycle.
All organs of the male reproductive system, including the prostate, tend to stay healthy in the presence of adequate levels of key hormones, including testosterone, says Dr. Shippen. “Normal concentrations of testosterone and its more powerful derivative may well be harbingers of prostatic health, not illness.”