Like many men past 40 I have started to pay more attention to articles in the press about prostate cancer. But the statistics seem more opaque than almost any other data presented to the public. At one level we have the stats that prostate cancer is the most common or second most common form of cancer amongst men in the UK, killing about 10,000 men a year. As a result there have been campaigns to raise awareness of the symptoms, including one using old recording of Bob Monkhouse, a UK comedian who died of prostate cancer.
On the other hand there is a growing backlash against the PSA test (a blood test which is supposed to indicate an increased likelihood of prostate cancer), and against treatment. The complexity appears to be that prostate cancer develops very slowly in most cases.
The following statistics were issued as part of a BBC radio broadcast on 6th September 2007 (the Check UP programme), and I can make no claim for their veracity.
- Only 5% - 10% of men who have prostate cancer will die of it.
- About 30% of men who have a positive PSA test will actually have prostate cancer
- About 25% of men, in the same age group, who have not had a PSA test will have prostate cancer
The figures above suggest that, in the absence of other symptoms or causes, the PSA test is not very useful. A digital rectal examination (in this case the digit means a finger, not some form of technology) is more indicative, but men are reluctant to ask, and many doctors seem reluctant to bring the topic up. A prostate biopsy is highly accurate, but painful, expensive, and can cause issues such as bleeding.
One of the main concerns, of some specialists, like the specialist on the BBC, is that to know that you have a cancer is worrying. But for 90-95% who have the cancer it will not kill them, and in most casement no treatment is the best treatment. Is it better for most people who have the non-threatening form of prostate cancer not to know?
A similar argument applies to some of the genetic tests that private companies are beginning to offer. Do people benefit from knowing they have an increased risk of disease A or B, or are they better getting on with their lives?
A complete transcript of the programme will be available on the BBC website in a few days.