What every woman needs to know?

Last week the model Emma B helped to launch this year's Breast Cancer Awareness Month by waving a pink bra above her head on Hungerford Bridge in London. A woman's risk of getting breast cancer, we were told in the reports on this event, is one in nine. But what is Emma B's chance? As a woman under 25, she has a one in 15,000 risk of developing the disease this year. The oft-quoted one-in-nine actually refers to a woman's lifetime chance of getting breast cancer. But how many articles have you read that explain that?

The pink ribbon is 10 years old this year. Started by Estée Lauder in the United States, breast cancer awareness campaigns now run in 40 countries. Since 1992, 17 million ribbons have been distributed. There is no doubt that we are all more aware of breast cancer, but how much do we really know about it? Does checking one's breasts reduce one's risk of dying from the disease? Is it just lumps that you need to look out for? How many lives does screening save? And who is most at risk?

A decade on, women are still confused. A survey by Breast Cancer Care last week showed that one in three women are still baffled about breast awareness. Half of the women questioned did not know that the risk of breast cancer significantly increases with age. The most commonly touted statistic about breast cancer is that it affects one in nine women. Eighty per cent of those cancers, however, occur in women over 50. Many of the women surveyed thought they should only check their breasts for lumps. In fact, the only signs of the disease will sometimes be a nipple rash or skin dimpling.

Getting these messages across will save lives. Breast Cancer Awareness Month is not a fuss over nothing. While lung cancer is Britain's biggest cancer killer, breast cancer is our most common cancer. In 1998, 38,780 men and women developed lung cancer. In the same year, more than 39,000 women were diagnosed with breast cancer.

But does awareness also cause unnecessary anxiety and panic? One problem is the media's appetite for young women. A few years ago, Breakthrough Breast Cancer decided to promote the campaign using only women of a representative age – that is, over 50. "To be honest, it was really hard work trying to get them interviewed in the media," says Delyth Morgan, chief executive of Breakthrough Breast Cancer. Most of the women who are telling their stories in newspapers and magazines this month are under 40. Stories of young mothers and glamorous singles is their twenties make much better copy.

As a result of this false impression, Professor Michael Baum, a breast cancer surgeon and Emeritus Professor of Surgery at University College London, believes that Breast Cancer Awareness Month causes more harm than good. "It's a double-edged weapon," he says. "I'm all for educating the public, but I resent the way it patronises women. It frightens a lot of young women unnecessarily."

Breast cancer charities argue that it is better to know more about a disease that kills 1,000 British women a month than to save young women from worry. "This is an important issue for women," says Dr Leslie Walker, head of information at Cancer Research UK. "This is a disease that affects a lot of us and we want to make a fuss about it. We live in an age of information. If we have a one-in-nine lifetime risk of breast cancer, let's know that, get used to it and decide what we want to do about it."

Encouraging women to check their breasts has long been a cornerstone of the campaign, but Professor Michael Baum believes that it is a "thoroughly bad idea". His view is supported by a trial reported in the Canadian Medical Association Journal last year. It found that by checking her breasts every month, a woman does not significantly reduce her chances of dying from breast cancer and increases her likelihood of unnecessary biopsies. As a result of similar studies, British GPs were recently advised by the government not to recommend routine self-examination.

In fact, most British breast cancer charities accept this and no longer advocate a strict routine of breast examination. They simply argue that looking out for the signs of breast cancer is common sense. "Would you rather be diagnosed with a small breast lump or a much larger one?" asks Dr Leslie Walker. "The data is very clear. Early-stage breast cancer has a 95 per cent survival rate after five years. It's a very different picture for bigger lumps or lumps which have spread." They recommend that women know the symptoms and tell their doctor if they spot them.

The other message of Breast Cancer Awareness Month is – go for screening. "There's been a 20 per cent reduction in the breast cancer mortality rate in the last decade and I believe that screening has had an impact on this," says Delyth Morgan. She points to a recent World Health Association evaluation that showed there is a 35 per cent reduction in mortality from breast cancer among screened women aged 50-69 years old.

Women between 50 and 64 are now invited for screening in Britain; women aged up to 70 will be included by 2004. Breast cancer charities also stress that women over 70 are entitled to screening, but must invite themselves. "Our research has shown that older women no longer think they are at risk from breast cancer because they are no longer being called for screening," Morgan says. The opposite is true. By the time she reaches 80, a woman has a one in 10 chance of developing the disease.

Professor Michael Baum does not believe screening is worth the expense. He points out that the best current estimate (presented to the US government this month) is that you need to screen 1,224 women aged over 50 for 14 years to prevent one death. "That one life is of infinite value," he says. "Screening is not something you give up lightly, but the personal chances of benefiting are small and I believe it would have been abandoned if it wasn't such a political hot potato."

He believes that the fall in breast cancer deaths is almost entirely due to the drug tamoxifen, and says that money spent on screening could be better spent on improving specialist care. "My advice to women is that if, God forbid, they do get breast cancer, they should make sure they go to a specialist centre," he says. "If I had the ear of the Government, I'd put all my resources into specialist teams."

Delyth Morgan, however, does not believe that women should have to choose between early detection via screening and top quality treatment once they are diagnosed with the disease. "Professor Baum's argument assumes that there are finite resources," she says. She points out that most of the cancers picked up by screening are at an early stage with five year survival rates of more than 90 per cent.

In fact, survival rates from breast cancer in Britain – for so long amongst the worst in the world – are now improving. Deaths from breast cancer have fallen by nearly a third since 1992. Although Britain is still lagging behind the US and other Western countries, this reduction in the number of people dying from our most common cancer is the biggest fall anywhere in the world.