|
Lack of accuracy has made PSA testing for prostate cancer controversial, especially since no-one is sure of the right treatment for early prostate cancer. But now suspicions have been confirmed that a high proportion of men can have prostate cancer with 'normal' or low PSA levels. The PSA is a blood test which if it's high indicates an increased risk of prostate cancer. It's not diagnostic and is far from 100 per cent predictive, although a high and rising level is worrying. The lack of accuracy has made the PSA controversial, especially since no-one is sure of the right treatment for early prostate cancer. But now suspicions have been confirmed that a high proportion of men can have prostate cancer with 'normal' or low PSA levels. In a prevention study where men were biopsied regardless of their PSA level, the rates of cancer were reported in 3000 men aged 62 to 91 with PSA levels under a cut-off of 4 nanograms per milliliter. The rate of cancer at biopsy ranged from about 6 per cent in men with PSAs of up to 0.5, to nearly 27 per cent in men in the range 3-4. Many of the tumours had the potential to become nasty. So should the alarm bells ring at lower levels? If so, large numbers of men would have unnecessary biopsies - and there's even debate about them (6 bites or 12)? And still no-one knows if PSA testing save lives even at existing levels. Much better tests and treatments are clearly needed.
|
