Prostate Cancer
These FAQs relate to a media release dated 1 April 2004 - "National Health Committee says "No, not yet" to prostate cancer screening "
Questions and Answers
What is prostate cancer?
Prostate cancer is the most commonly diagnosed cancer in New Zealand men and the third most common cause of male cancer deaths. It accounts for 3.8% (555 in 1999) of male deaths in New Zealand, with about two thirds of those occurring in men aged 75 years and older. Prostate cancer is rare in men below the age of 50. More than 60% of all new cases of prostate cancer are in men aged more than 70 years.
The prostate is a small gland that sits just below the bladder and surrounds the top part of the urethra. The growth and development of the prostate depends on testosterone. It is common for the prostate gland to get larger as men grow older and this enlargement is called benign prostatic hyperplasia (BPH). Men with early prostate cancer are unlikely to have any symptoms as these only occur when the cancer is large enough to put pressure on the urethra or disturb bladder function. Many older men have enlargement of the prostate due to non-cancerous BPH.
A blood test may be done to check for the presence of prostate specific antigen (PSA). The PSA test is currently the best method of identifying localised prostate cancer. A raised PSA can be an early indication of prostate cancer. The PSA test can fail to detect prostate cancer. If the level of PSA in the blood is raised, this may indicate that prostate cancer is present. However, most men with a raised PSA will not have prostate cancer: only one out of five men will turn out to have prostate cancer.
If cancer is detected, there is currently no way of telling which cancers will cause harm. About 90% of men diagnosed with early stage prostate cancer will still be alive 10 years after being diagnosed even if they don’t have any treatment. In some cases, prostate cancer never causes problems or shortens life. It is not yet proven that treating prostate cancer is better than not treating it.
Treatment options for prostate cancer:
- Radiotherapy:
This involves a course of radiotherapy on the prostate gland at an outpatient clinic. The aim is to cure the cancer, although there are possible side-effects. Erection problems may be suffered by between two and six of every 10 men. Up to one in every 10 men may experience diarrhoea or bowel problems and up to one in every 20 men may experience bladder problems.
- Surgery:
This involves an operation to remove the prostate gland. The aim is to cure the cancer, although again there are possible side effects, including death. Up to two in every 10 men may experience some bladder problems and between two and eight out of every 10 men may experience erection problems after surgery.
- Active Monitoring:
This involves not treating the cancer but undergoing regular check ups to monitor the cancer and check that it is not growing. Many cancers do not cause any problems. The advantage is that for many men it avoids the side effects of radiotherapy and surgery. If there are signs that the cancer is growing, treatment will be offered. The disadvantage is that the cancer may grow to a more advanced stage. Some men find not knowing difficult.
Can a man still ask for a test?
Although there is concern over the potential harms of prostate cancer screening, men should not be denied the ability to request the test if they are fully informed. The committee considered recommending that if men wished to have a PSA test they should pay for it themselves. However, it felt that the better approach would be to educate and inform men and health professionals about the evidence around prostate cancer screening and allow men to make an informed decision based on good information.
Why has there been an increase in prostate cancer screening?
There has been a rapid increase in screening for prostate cancer despite there being no conclusive evidence that prostate cancer screening is effective in reducing deaths associated with prostate cancer. It is likely that this increase has occurred because of growing public concern about health issues generally and a greater demand for the PSA test by men and their families worried about the disease.
What should men do if they have symptoms?
If a man notices any changes or problems with their urinary function they should consult their doctor. Symptoms such as a weak urinary stream or difficulty starting or stopping urination, can be caused by a number of medical problems like an enlargement of the prostate.
Why do women have two national screening programmes when men have none?
There is good scientific evidence that breast cancer screening reduces deaths from breast cancer and that cervical screening reduces the risk of developing and dying from cervical cancer, which is why there are national screening programmes for these two cancers.
As the NHC review has confirmed, that evidence - which is essential if you are going to start a screening programme -isn't there for prostate cancer screening at this time.
What happens next?
The committee is recommending that the Ministry of Health should review evidence from Randomised Control Trials (RCTs) on the benefits and harms of prostate cancer screening and conduct a formal assessment in 2008.