When breast screening is best

Women will continue to be screened for cancer, whether or not the tests really save many lives

Professor Michael Baum, the eminent cancer specialist, was nursing his wounds yesterday. He had just rubbed up against the politics of the breast and he found the encounter bruising. "I'm one of the good guys," he said, aggrieved and in a state of some shock. "I want to save women's lives from breast cancer as much as the rest of them."

Resigning from the Government's breast cancer screening advisory group, his suggestion that the programme may be turning out to be an expensive mistake was greeted with howls of outrage from other breast cancer doctors. There are certain holy of holies you do not lay a finger on, and the breast programme is one.

The medical politics of the various parts of the anatomy are curious. Take the colon, for instance, a sluggish tract of unappealing aspect. It just doesn't have the glamour of the heart or the kidney, let alone the beautiful breast. Yet the same number of people die every year from colonic cancer as die of breast cancer: 15,000 a year in England and Wales. Breast cancer, once detected, is hard to treat effectively, while precancerous polyps in the colon are 100 per cent treatable. There is now a highly cost-effective once-in-a-lifetime test that not only detects but removes polyps. But where are the colon campaigners? There are no politics in the colon.

Some 8,500 men die annually of prostate cancer. It can be detected, but since a quarter of 70-year-olds have it, selecting the dangerous ones is difficult. However there is only the beginning of a men's prostate campaign. For some reason men are just not as worried about their prostates as women are anxious about their breasts. The prostate lacks a certain something. Perhaps that is because testicles are not encased in little lacey under-wired numbers and their cleavages do not feature on billboards reading: "Hello girls!"

All that fetishism has turned the breast into the most politically powerful organ in the body. Hardly surprising that fear of breast cancer stirs something deep in women's psyche, fear of dying for the organ that attracts men and suckles infants, fear of disfigurement that seems to threaten everything. Those who run walk-in screening clinics are familiar with women who suffer from obsessional fear of this disease. Few women take the radical step of having their healthy breasts removed in order to escape the risk altogether. After all, the breast is not essential, we could do quite well without them and mass mastectomies on adolescent girls would save all their lives. But few opt for mastectomy even after they contract cancer. So strong is the power of the breast that women will risk death to keep them: curious but true.

Screening was campaigned for over many angry years, but successive health ministers balked at the cost. It took a particular set of circumstances to get it started. A key report recommended it; the 1987 election was looming; Edwina Currie as junior health minister supported it; and in the pre-election run-up it went through - a symbol of the government's good intentions towards the NHS and female voters.

No one is now suggesting it is a bad thing, and the figures may yet prove it really does do good. There are simply doubts about whether the project saves enough lives for the money that could be spent on improving often very bad treatment for those already diagnosed. Screening costs pounds 27m and its advocates claim it saves 1,250 lives a year.

But medical statistics are ankle-deep in factoids. Professor Alan Maynard, the distinguished health economist and doctor-debunker, takes a laconic view of the statistical habits of the medical profession. "They're all buccaneers," he says, and complains that breast screening was started on the basis of flimsy evidence. He calls for analysis by statisticians, not by those with a professional interest in the programme.

These are the problems: death rates from breast cancer have been falling steadily since 1985, probably because of better treatments, such as Tamoxifen. Yet some claim this as a success for screening. Other problems abound: imagine two women contracting cancer at the same time who die on the same day. One was screened, diagnosed and treated five years earlier than the other. Statistically the one diagnosed first will be counted as having survived longest, a triumph for intervention compared with the woman who died shortly after detection. But the course of the disease may have been identical in both women. Also, every time an early cancer is removed it will be clocked up as a success for early detection because it did not reappear, though it may never have been threatening in the first place. These are just some of the questions Baum, Maynard and a few others are raising.

Underlying this arcane dispute is the odd assumption that we are rational about how money is spent on health. We are not and probably never will be. People worry about the wrong diseases. Some useless treatments may make people feel better without being any better, as the power of the placebo effect shows. People want something done even if it does no good, which is why many visits to GPs are a waste of time. For many drugs do no good and many operations have no benefit.

Medicine is about making us feel better in all kinds of ways, far beyond the rational universe of the health economists. We want comfort and reassurance, irrational treatments that we believe in, things we like and trust. And so it may turn out to be with breast cancer screening.

Here I will come clean. I was screened on a special programme for women at high risk of breast cancer because they have a history of the disease in close relatives. A small cancer was detected, first one then another small slice was excised, and now, taking Tamoxifen, I hope to survive. If I do I will be grateful to the screeners and the hospital. However, if I survive, according to present statistics, no one will really know whether that cancer was life-threatening in the first place. But even if it turns out that screening doesn't do much good, and early detection is not particularly important, like most other women I would still want to be screened in order to know the best or worst. Reassurance is a treatment too, a treatment for anxiety.

In any case, as Professor Maynard says wearily, there is no chance, no chance at all that the screening programme will come under any threat, unless it turned out to be positively dangerous. With 90 screening centres, many jobs and careers involved, money firmly allocated, what health minister would dare to stop it? In the scheme of things, pounds 27m is a very small slice of NHS funds. It may turn out that the money is not being spent on saving many lives from breast cancer, but it will still be money well spent in the less rational business of reassuring women that they are clear of the disease. It will be money well spent on making us feel better, and there is no neat line between the value of being better and feeling better.