Myth No. 1: Eating tomato-based foods with ketchup and red spaghetti sauce can prevent prostate cancer. Dr. Alan Kristal, deputy director of the Hutchinson Center’s Cancer Prevention Program and a national prostate cancer prevention panel, says, “The vast majority of studies show no link between the two.” Kristal and colleagues last year published the results of one of the largest studies to date on whether foods containing lycopene, a nutrient that makes tomatoes red, actually prevent prostate cancer. By testing lycopene levels in the blood of 3,500 men nationwide they found no link. Myth No. 2: High levels of testosterone increase the risk of prostate cancer. Kristal says, “That’s a very cute assumption – based on a very simple understanding of the metabolism of testosterone and the impact on prostate cancer, which is unfortunately wrong.” Unlike the strong link between estrogen and breast cancer, there is no link between testosterone levels and prostate cancer risk, he said. A 2008 study published in the Journal of the National Cancer Institute, a top international journal, combined data from 18 large studies and found no link between serum testosterone concentrations and prostate cancer risk, and more recent studies have further confirmed this conclusion. Myth No. 3: Cod liver oil (Omega-3 fatty acids) can reduce prostate cancer risk. Kristal says, “Based on the link between prostate cancer and inflammation and the anti-inflammatory effects of omega-3 fatty acids, this sounds reasonable.” Yet two well-designed bulk studies (one of which was led by Kristal and published last year in the American Journal of Epidemiology) have shown that high omega-3 fatty acids in the blood instead increase the risk of prostate cancer. Myth #4: Dietary supplements can prevent prostate cancer. Several large, randomized clinical trials have studied the effects of dietary supplements on a variety of cancers, including prostate cancer; the results show either no effect, a significant effect – or, worryingly, a significant increase in risk,” Kristal says. “The more we think certain dietary supplements can help, the more they seem likely to increase cancer risk. ” For example, the largest prostate cancer prevention study to date: the Selenium and Vitamin E Cancer Prevention Clinical Trial (SELECT) was earlier called off because neither selenium or vitamin E supplementation alone nor combined supplementation had any effect on reducing prostate cancer risk. A selective follow-up study published in JAMA last year found that vitamin E actually increased the risk of prostate cancer in healthy men, and the Hutchinson Center reviewed the analysis of data from the study, which included nearly 35,000 men from the United States, Canada, and Puerto Rico. Myth #5: We don’t know which prostate cancers screened for by PSA (prostate-specific antigen) need to be treated and which don’t. Dr. Ruth Etzioni, a biostatistician and member of the Hutchinson Center’s Department of Public Health Sciences, says, “The truth is, we know exactly which cancers are less likely to be malignant and which ones are likely to metastasize if left untreated.” In addition to serum PSA levels, criteria for determining tumor aggressiveness include tumor volume (the number of biopsies containing cancerous tissue) and the Gleason score (which predicts tumor aggressiveness by looking at a sample of cancerous tissue under a microscope). 2-5 on the Gleason scale is low risk, 6-7 is intermediate risk and 8-10 is high risk. Myth No. 6: Only one in 50 people with prostate cancer diagnosed through PSA screening benefit from treatment. ”This data from the preliminary publication of the ‘European Randomized Trial of Prostate Cancer Screening’ is clearly wrong,” Etzioni said. “The data produces a very unfavorable harm-to-benefit ratio for PSA screening. It implies that if there is one person whose life is saved by PSA screening, there are 50 people who are simultaneously overdiagnosed and overtreated.”