The tube through which urine flows from the bladder when you pass water goes first through the prostate gland then out through the penis. The prostate gland can become enlarged in many men as they get older which then causes difficulty with urination.

The job of the prostate gland is to produce fluid which forms part of semen and helps to nourish sperm. The prostate gland sits in front of the back passage or "rectum" which is why if a doctor wants to examine the prostate gland they feel it by putting a finger into your back passage. This is also called a "digital rectal examination" or DRE for short. From feeling the prostate gland the doctor can tell how enlarged the gland is and whether it feels normal or cancerous, this can then provide a picture of prostate cancer if it exists.

If you are below they age of 50, you are extremely unlikely to have it. Simple as that, and the information leads to the best preventative: regular screening after age 50. In addition to age, there is a genetic risk as well.

If you have more than one close women relative who has had breast cancer or a father or brother who have been diagnosed with prostate cancer, your chances increase even more. This is an indication that a faulty gene is the culprit and is being passed through your family. And what your family's ethnicity is can also be a risk.

Recent studies have shown that men with African ancestry are twice as likely to develop prostate cancer as white men, and white men are twice as likely as Asian men. Why this should be so is not immediately clear, and it may be complicated; having to do with diet and lifestyle as well as dominant malfunctioning genes.

All this is well and good to know, but it doesn't do you any good if you can't control it, does it?

Age is the main risk factor for developing prostate cancer. As men get older they have a higher chance of developing all types of cancer including cancer of the prostate. Prostate cancer is quite uncommon below the age of 50 years however four out of every ten men who are 70 years or older will have the illness. Many of these men will live normally without knowing they have prostate cancer and without it giving them any symptoms or shortening their life span.

Hormones

How about location in the world?

If you live in North America or Western Europe, you are at slightly more risk than anywhere else. This may be a dietary difference or hereditary, but the picture is not yet complete. It may even simply be a result of more often and more aggressive testing procedures in the "developed" world. There is a large ongoing study in Europe called EPIC (European Prospective Investigation into Cancer and Nutrition) to try to determine the correlation between European diet and prostate cancer, but results won't be in for another ten years.

So it seems to be premature to move outside of these two areas of the world. But how about avoiding prostate cancer by already having another common disease in men?

A recently completed study showed the surprising fact that men who have had diabetes for several years have a significantly reduced chance of getting prostate cancer (American Journal of Epidemiology 2005 161(2);147-152).

Diet may have an influence on the development of prostate cancer. Prostate cancer is more common in men who have a "western" diet high in saturated fats. Saturated fats are found in red meats such as beef, lamb etc and in some dairy produce e.g. butter and things made with butter e.g. cakes, biscuits etc., and also in highly processed foods e.g. ready meals. It seems that men who have a diet high in saturated fat are at increased risk of developing prostate cancer. It is also widely believed that a diet high in fruit and vegetables helps to prevent many cancers. This may be through the action of cancer protective chemicals found in many fruit and vegetables known as "anti-oxidants". This is one of the reasons it is recommended that we include five portions of fruit and vegetables in our diet every single day.

Genetic

Age. That's it. Age is the only reliable cause of prostate cancer. All the others are only potential risk factors that are still too early in their stages of study to know exactly what do about them or what they mean. When you get old your skin wrinkles, you get arthritis, and you get prostate cancer. It's simply a fact of life.