Prostate Cancer
This is the most common cancer affecting men, 50 years of age and over, in North America. Prostate cancer is a slow-growing abnormal growth that starts within the prostate ducts and glands. This can be diagnosed with a DRE as the gland will often feel different than a non-cancerous one. An abnormal PSA test and a positive prostate biopsy will also help the doctor make a definitive diagnosis. Sometimes the gland can feel completely normal and the diagnosis made through an abnormal PSA test. That is why the PSA test should be done yearly.
Why is Prostate Cancer so common now?
No one knows the exact cause of prostate cancer but there are factors which explain why it is so common now. The population is aging and the rate of prostate cancer increases dramatically after the age of 65. This is a disease that is linked to age. There is more knowledge and understanding of the disease as well as improved diagnosing techniques so it is easier to diagnose prostate cancer, especially at an earlier stage. Our success in treating prostate cancer is improving too.
Studies have been done to link diet to prostate cancer. Although the results are not definitive, it is generally thought that a high-fat diet stimulates cell growth and division thereby increasing the risk of prostate cancer.
Can I prevent Prostate Cancer?
At this time, there is no known method of preventing prostate cancer. However, with ongoing research, there are suggestions how to minimize your risk. A high-fibre diet as well as raw vegetables such as broccoli appear to have protective properties against cancer. Some investigations have suggested a diet rich in Vitamin A is helpful too.
How is Prostate Cancer Diagnosed?
The cause of prostate cancer is unknown. It is known, however, that the growth of cancer cells in the prostate, like that of normal prostate cells, is stimulated by male hormones, especially testosterone.
The spread at which cancer grows in the prostate varies from man to man. In some men the cancer grows slowly; in others more rapidly. The risk of developing prostate cancer increases with age, with more than 80% of cases diagnosed in men over the age of 65.
When a cancerous prostate tumour is small and located only within the prostate, the cancer often is not detected. It may not cause any symptoms and may be too small for a doctor to feel during a routine prostate examination. A doctor performs this examination, which is called a digital rectal examination (DRE), by inserting a finger into the rectum to feel the size and shape of the prostate.
A man may live for many years without ever having the cancer discovered. As the cancer grows, however, the prostate may eventually squeeze the urethra, which it surrounds. Then, symptoms such as difficulty urinating may develop. This is usually the first symptom of prostate cancer. (It is important to note that difficulty in urinating can be caused by other, noncancerous conditions of the prostate and does not always mean that prostate cancer is present.)
With or without symptoms, a growing cancer can also begin to attack cells close to the prostate. At the same time, cells can break off from the cancer and spread to other parts of the body. The sites to which the prostate cancer tends to spread are the lymph nodes, various bones, especially the bones of the hip and lower back and less often in other sites such as the lung and the liver.
Like the main prostate tumour, the tumours that have spread to other areas of the body expand and squeeze other body parts. When prostate cancer spreads, the most common symptoms is often bone pain.
In addition to a DRE, your doctor may recommend a test to measure prostate specific antigen (PSA) in blood. PSA is a substance produced by both normal and cancerous prostate cells. When prostate cancer grows or when other prostate diseases are present, the amount of PSA in the blood often increases. If either the DRE or the PSA blood test is positive, it is recommended that a transrectal ultrasonography (TRUS) test be performed to verify the results.
To detect prostate cancer and to determine the size and extent of the spread-or stage - of the disease, your doctor may perform tests that involve feeling the prostate, looking at internal parts of the body, measuring the levels of substances in the blood, and examining samples of prostate cells.
"We appreciatively acknowledge the support of this Web site through an educational grant from AstraZeneca."