Three of the most widely used screening tests in medicine have taken a hit lately and been cast into disfavor or abandoned.
The Prostate Specific Antigen (PSA) test has been condemned as useless in saving lives and accused of leading to unnecessary surgical interventions. This test, which had previously been popular as a screening tool for prostate cancer in men over 50, is now reviled. It not only does not reveal cancers that lead to loss of life, but it leads to unnecessary biopsies and surgeries that can result in impotence and incontinence. It is no longer recommended.
Mammograms have also run aground amidst accusations that they cause the very problem they are intended to prevent – breast cancer. The radiation risk from repeated mammograms puts women at a higher risk of getting breast cancer, not a very good trade-off when alternatives are available. And mammograms too lead to aggressive treatment which may not be necessary in many cases. A better testing tool is breast thermography, which detects heat changes from abnormal tissue growth. Thermography does not involve any exposure to radiation.
And now colonoscopies have been questioned as well. An editorial in the Nov. 9, 2011 issue of the Journal of the National Cancer Institute suggests that colonoscopy as a screening tool has not been adequately investigated for benefits and harms. Colonoscopy is expensive and prone to overdiagnosis and overtreatment as well. The primary result of colonoscopies is the removal of benign polyps, which are not cancerous. A better strategy, these authors suggest, may be to screen for blood in the stool with a simple test and perhaps perform limited flexible sigmoidoscopy before recommending a full colonoscopy. The strategy of screening for blood and performing a sigmoidoscopy has been shown in controlled studies to reduce mortality from colorectal cancer, but no additional benefit has been shown from performing an additional colonoscopy.
Perhaps our focus should shift from unproven, expensive, and invasive screening tests to a strategy of prevention with supportive measures. Certainly limiting alcohol and tobacco use are proven methods of reducing cancer risk. Avoiding known carcinogens in the form of petrochemicals in household products, pesticides in foods, and skin care products (soaps, shampoos, moisturizers, deodorants) makes sense. Eating a primarily whole foods diet with minimal amounts of processed food products will provide essential vitamins and minerals. A diet focusing on plenty of fresh fruits and vegetables along with clean, preferably organic protein sources is ideal. A program of regular exercise is also essential for maintaining a resilient immune system.
Vitamin D supplementation is probably the most important single measure for preventing these cancers. A sensible strategy is to take 5,000 IU of vitamin D3 per day and then testing 25-hydroxy vitamin D levels to make sure this an adequate dose. Levels should be in the range of 40-100.
Taking antioxidant supplements is another preventive measure that can help avoid abnormal tissue growth and the deleterious effects of aging on cells. A potent antioxidant program could include resveratrol, alpha lipoic acid (or r-lipoic acid), astaxanthin, Coenzyme Q10 (CoQ10), and n-acetyl-cysteine (a precursor of the body’s own antioxidant glutathione). Taking a high quality multi-vitamin supplement can also supply the cofactors necessary for detoxification and prevention of oxidation in the body’s tissues, supporting healthy organ function.