Prostate cancer: risk factors

The causes of prostate cancer are largely unknown, but the main established risk factors are as follows:

• Age - Prostate cancer is relatively rare in men aged less than 50; thereafter risk increases steeply with increasing age.

• Family history - A family history of prostate cancer, breast cancer, and possibly some other cancers, especially occurring at a young age is associated with an increased risk of prostate cancer.

• Ethnic origin - Risk tends to be higher in men of African descent, and lower in men of Asian descent.

• Hormones - There may also be a hormonal link to prostate cancer, given that the hormone testosterone seems to have an active role in promoting or triggering it, whereas the hormone oestrogen appears to have the reverse affect.

• Genetic factors - Some men can be at increased risk due to inherited genes which are faulty, such as BRAC2, which also has a role to play in breast cancer (and there may be a link between a family history of breast cancer and propensity to develop prostate cancer). There is also some research to show that men with Lynch syndrome have a 2.1-4.9 times higher risk of developing prostate cancer than the general population (Ryan, Jenkins and Win, 2014).

• Diet - The precise role of diet is unclear. Risk appears to be increased by a diet high in animal fats, including dairy products, and calcium.  Risk may be reduced by a diet high in fruit and vegetables, and more specifically by lycopene (as found in tomatoes), selenium, and vitamin E.

•  Occupation - There is some research to support occupational exposure to pesticides increasing the risk of developing prostate cancer.