Leading article: Second opinion

A comparative study of prostate cancer rates in Britain and America raises that classic medical dilemma: can the treatment actually be worse than the disease itself? The US experience of the past two decades suggests that earlier screening and more aggressive treatment can increase survival rates. This sounds like good news; and such a study would normally lead to calls for the NHS to follow the US example. But more widespread screening and aggressive treatment bring their own problems for patients.

The explanation lies in the particular nature of prostate cancer. As one of the report's authors notes: "You detect a lot of prostate cancer if you look for it and much of it is indolent." Much of it is slow-growing and does not necessarily affect the quality, or length, of a person's life. One is actually more likely to die with it than from it.

Yet tell most people they have a cancer and they usually request that attempts are made to remove it. The authors of this report fear that many men in America are opting for aggressive treatment that can leave them impotent, or incontinent, to little long-term benefit to their health. We need more information. Two large trials of those who have contracted the disease should help us come to a better judgement about the merits of early treatment, as opposed to a more patient, risk-evaluating, approach.

But we should recognise that this is merely one of the questions raised by advances in disease screening. Would patients want to know if they had a hereditary predisposition to Parkinson's or Alzheimer's? Ignorance is hardly bliss, but one can envisage times when patients might choose not to know.