Current test for prostate cancer is inadequate

May 27 2004

Britain’s top cancer scientists claim that men’s health is at risk because the current test for prostate cancer is inadequate. The warning comes as The Institute of Cancer Research launches the 7th Everyman Male Cancer Awareness Month to alert men to the risk of prostate and testicular cancer.

With research into male cancers still 10 years behind other cancers, the Everyman scientists are calling for £500,000 to help fund their research into developing better methods of testing men for prostate cancer. Prostate cancer is now the most common cancer to affect men in the UK, with 27,000 diagnosed each year, and one man dying from the disease each hour.

Recent research shows that half of all men who are diagnosed with prostate cancer by PSA testing do not need any treatment at all for their cancer, but the PSA test is incapable of discriminating between those who do need treatment and those who do not.

The controversial PSA test is currently the only method of screening for early prostate cancer, but many doctors believe it to be too unreliable to recommend to patients routinely.

Professor Colin Cooper, Head of the Everyman Male Cancer Research Centre at The Institute of Cancer Research comments:

“PSA testing has two major failings; firstly it doesn’t detect all cancers, and secondly when it does detect cancer it cannot predict how that cancer will behave. This often results in men being given invasive treatment that they do not require. What we
urgently need is a test which can differentiate between cancers that are aggressive, the tigers, and those that are pussycats, but meantime PSA is the best we’ve got.”

Treatment options for prostate cancer most commonly include the removal of the prostate (prostatectomy), radiotherapy and hormone treatment, but these treatments can leave the patient with serious long-term side effects that can include incontinence and impotence. So ideally, such treatment would be restricted only to the 50% of prostate cancer patients who need it.

Dr Chris Parker of The Institute of Cancer Research comments:

“Prostate cancer is the only human cancer that is curable but which commonly does not need to be cured. It can often be so slow growing as to never cause the patient any ill effects. So it can be a case of the cure being worse than the disease. The challenge is to identify who needs to be treated and who doesn’t.”

By the age of 65, many men will have some cancer cells in the prostate, but most will live out their natural span without the disease ever causing them any ill effects. This presents patients with the dilemma of whether or not to go for treatments which carry a real risk of incontinence and impotence.

In the United States men over 50 are routinely given PSA tests during health checks with more than half having a test each year. This level of testing has led to the incidence of prostate cancer in the USA more than doubling since the introduction of screening. The standard approach in the US is to offer radical treatment to all men with localised disease, resulting in up to 50% being over treated and subjected to significant risks of incontinence and impotence. Without a new prostate cancer test, this trend for PSA testing looks set to continue, and treating all cases in this way will become increasingly difficult to justify.

Dr Chris Parker at The Institute of Cancer Research is currently conducting a study of a new approach for men with early prostate cancer called Active Surveillance. Any men whose tumours show early signs of growth are treated, but the rest continue on the surveillance programme with no ill effects from the disease and no need for
treatment. Early results of the Active Surveillance programme suggest that two thirds of selected patients may be safely spared invasive treatment for their prostate cancer.

Professor Peter Rigby, Chief Executive of The Institute of Cancer Research concludes:

“At the moment we simply don’t know what causes prostate cancer. We desperately need more funds to enable us to carry out that research, and to develop a test which can distinguish between the pussycats and the tigers, between those men who can be spared treatment, and those with an aggressive cancer who need to have life saving treatment to beat the disease.”