Although prostate cancer is the most common male cancer in B.C. (with the exception of non-melanocytic skin cancer), relatively little is known concerning its etiology.
Ethnic origin appears to be important, with North American blacks having very high rates, whites intermediate rates and North American Asian men, low rates (Gallagher & Fleshner 1998). Family history is also important in prostate cancer. Men with a single first degree relative with the disease have a 2-fold risk of developing it themselves. Men with 2 or more first degree relatives involved, have a 4-5-fold risk. Fortunately only about 1% of men in Canada have such a history.
Consumption of a diet rich in red meat and saturated fat appears to increase risk, particularly of aggressive disease. At present compelling evidence for a protective effect of vitamin A, Beta-carotene, or soy products is lacking for prostate cancer, although results from ongoing or planned studies may alter this assessment in the next 2-3 years. A study conducted in Finland showed a substantial protective effect from vitamin E supplementation, but confirmation of these results is necessary.
Prevention
Primary prevention manoeuvres involving diet modification may eventually prove useful. Clinical trials are required in order to demonstrate benefit, however, before these can be recommended to men with any confidence.
Reference
- Gallagher RP, Fleshner N. Prostate cancer: epidemiology. Can Med Assoc J; 1998; 159:807-813