The prostate is a small organ or structure found at the base of the bladder, which is made up of muscle fibres and glands. The main function of the glands is to produce fluids that are mixed with sperm and to help the sperm fertilise an egg. A cancer is an uncontrolled growth of cells. Prostate cancer therefore refers to a cancer found within the glands of the prostate. As the cancer begins in the cells of the gland, it is also referred to as an adenocarcinoma. Prostate cancer usually starts in the outer portion of the prostate gland. This means that when the tumour gets large enough, it can be felt by a rectal examination. Like most cancers, prostate cancers can differ in their aggressiveness and size.
The cause of prostate cancer is not yet known though it appears to be as a result of inflammation or irritation in the prostate gland over many years. Some evidence suggests that more frequent ejaculation reduces the risk of getting prostate cancer. Diet also seems to play a role in developing prostate cancer and, as with other types of cancer, there is some evidence of a genetic or inherited risk as well.
Prostate cancer is usually diagnosed by a biopsy. In New Zealand, prostate cancer is the most common cancer diagnosed in men.
Before doing a biopsy, however, the doctor will look at your PSA (prostate-specific antigen, a protein produced by the prostate gland) levels, do a rectal examination of the prostate and maybe perform an MRI. A biopsy involves removing a small amount of tissue from the prostate, which is sent to a pathologist for further analysis to confirm your diagnosis.
The treatment of prostate cancer depends on several factors - the age of the person affected, the medical conditions which the person has, and how bad the cancer is. The problem in treating the prostate is that these treatments often affect the structures which surround the prostate. These are the nerves which control erections, the muscle which stops urine leaking and the rectum.
Generally, if the cancer is found early, we watch the cancer and treat only if the cancer seems to be growing. With more advanced cancers, the prostate can be removed with surgery or the cancer treated with radiotherapy. If you have surgery to remove the prostate, you will become infertile. For cancer that has spread around the body, the treatment options include medication known as androgen deprivation therapy and radiotherapy, or both together.
At Urology Waikato, we have particular interest in the diagnosis and management of prostate cancer, including biopsy, imaging and treatment.
With respect to this, we are delighted to offer New Zealand's only MRI/ultrasound fused biopsy service. This special ultrasound machine imports pictures from the MRI and links them to the pictures from the ultrasound, allowing for a much more accurate biopsy than the standard ultrasound-only biopsy. This accuracy means that the biopsy is more likely to correctly show whether cancer is present or not, and how bad the cancer is.