It is about the size of a walnut and is located below the bladder and in front of the rectum. Over the next decade it has been predicted that the incidence will rise considerably, overtaking lung and breast cancer. This is largely due to a likely increase in numbers of cases diagnosed, through the greater use of PSA tests, and an ageing population. Little is known about the detailed or molecular mechanism of development of prostate cancer. The cancer genes involved in the development of this disease have not yet been identified.
Prostate cancer can run in families.
Men with a brother or father who developed prostate cancer have a 3-5 fold increased risk. Studies of Asian immigrants to the US show that whilst those brought up in Asia have a low incidence of prostate cancer, Asians raised to adulthood in the US acquire that country's higher risk. The observation suggests that environmental factors, which are different between the two countries may influence the incidence of prostate cancer. It has been suggested that selenium and vitamin E in the diet may protect against prostate cancer. The majority of men with prostate cancer are aged over 60 years, although this cancer can also occur in younger individuals.