Could the secret to cancer protection be found in the blood?

After her mother had breast cancer, Sophie Radice was told she too was at high risk. But doctors could not agree on the best way to protect her. Why?

I'm no hypochondriac. I don't even think I am one of the "worried well". And when I first found a lump in my breast, I didn't think I should be seen any quicker just because my mother had breast cancer. My GP's National Institute for Health and Clinical Excellence (NICE) guidelines reassured me: they said it is only likely that a family has a "cancer gene" if two or more close blood relatives on the same side of the family contract the same type of cancer, or those cancers occur at a young age.

Less logically, I felt that my family had used up all its breast cancer sympathy and horror. As a friend whose sister had breast cancer in her early forties put it: "It would seem like impossibly bad luck for everyone in the family to have to go through all that again."

My GP said that I seemed unusually relaxed about the lump. Perhaps as a consequence, I wasn't seen by a consultant for more than three months. But when I was examined, I was surprised to be given the full works: a total MRI body scan, a mammogram, a breast scan and a needle bioscopy. When I went for my results, the consultant told me that although he'd been 99 per cent certain that I had breast cancer, he was very glad to discover I hadn't. He was considered one of the top breast cancer specialists, and I didn't hear him refer to the NICE guidelines once. I got the feeling he didn't need to.

The next time I found a lump – again, as it turned out, a non-malignant cyst – a new consultant decided that I should come in every year for a mammogram and a scan – just to be "on the safe side". This worked for a couple of years. But on the third annual visit, yet another new consultant pointed out that, as my mother was 51 when she got breast cancer and I was a decade younger, my risk was no greater than other women's – so I should not be offered any more screening until I was over 50, "just like everyone else".

I stood slightly petulantly in the consulting room for a while, wondering if I should insist on being seen, if I should try to hold on to this reassuring annual gift the NHS had given me. After all, it hadn't been my own personal worry that brought me here, but a consultant's "gut feeling". I eventually decided that I should be glad to have been relegated down the ranks of risk, and not to make a fuss.

Then, this summer, I read about a national study by Macmillan Cancer Support and the Department of Health's genetics service. According to the study, at least 55 per cent of people concerned about a family history of cancer did, in fact, turn out to have an increased risk of cancer compared with the general population. I began to wonder if perhaps I had been fobbed off to save NHS money. Would I and others like me – people who knew of only one close relative to have had breast cancer – now be tested for an inherited cancer risk?

Well no, as it happens. Like everything about genetics, it's a good deal more complicated than that. Cancer genetics is a relatively new area of medicine. But publicity about breakthroughs in the detection of inherited cancer meant that, by the early Nineties, every regional genetics service in Britain was having to respond to a flood of cancer referrals. Many were like me: people who had a close relative with cancer, and who'd maybe had a few "scares" themselves, but were considered to be only at marginally increased risk according to the NICE guidelines.

The Macmillan and Department of Health project aimed to find the best way to ensure that high-risk families were being reached, genetically tested and counselled – and also that those at a marginally increased risk were reassured by well-trained doctors and nurses, rather than unnecessarily screened. "There would be little point treating anxiety with radiation," says Dr Paul Brennen, a consultant in clinical genetics who worked with the Macmillan project. "I would consider that it would be more dangerous to expose someone like you to yearly mammograms than it would be not to screen you."

Assessing risk is tricky, Dr Brennen says. Cancer genetics is developing fast; new genes are being discovered all the time. In May, a gene called RAP80 was identified. It may soon be added to the two breast cancer genes (BRCA1 and BRCA2) that geneticists already look for.

"Quite a large number of women, in the region of 30 per cent, would be considered to have what we call an inherited predisposition – which could be to do with a shared or similar diet or environmental factors," said Dr Brennen. "Within that, 5 to 10 per cent will have the BRCA1 and BRAC2 gene, which has to be taken from the DNA pattern of the patient who has had cancer, and then the relatives are tested. If the predictive test is positive it can mean that the relatives are 80 percent more likely to develop breast cancer."

In fact, the 55 per cent figure quoted in the headlines was not especially useful, says Professor Jane Maher, Macmillan's chief medical officer, because it didn't help public understanding of the cancer risk. "You cannot certainly predict that someone will get cancer or indeed that they won't," she says. "If you are put into a high-risk factor for developing breast cancer it doesn't definitely mean that you will get it, just as being put in a low-risk group doesn't mean that you are safe from cancer for the rest of your life. The Macmillan and Department of Health pilot aimed to inform people about what inherited risk really means."

So do I feel reassured? Not really. Three doctors who didn't want to be named told me that the NICE guidelines were "too complicated", "difficult to apply" and left them with the feeling that they might be missing cancers that ran in families because there were "black holes" and "grey areas". One doctor said it might not be accurate to consider me low risk because my mother had got pre-menopausal breast cancer, which is more likely to have a genetic factor. Another doctor said he thought he'd made one woman extremely anxious because he thought she should be tested for BRACA1 and 2, but she couldn't because both her relatives with breast cancer had died. A third said many women didn't know what their relatives had died of at all. Two of the doctors told me to get tested for breast cancer genes privately.

Janey Drewman's sister died of breast cancer at the age of 54, a year and a half ago. Janey herself, who is still in her forties, is not considered to be in the high-risk category. But she remains worried. "I think there's a lot that hasn't been discovered about cancer within families, just from families I know. I think if a close relative has died from cancer, you live with the feeling that it is just around the corner – whatever anyone tells you."

Professor Penelope Hopwood, who led a study of the perception of breast cancer risk for the Christie Hospital in Manchester, says Janey's feelings are understandable. "Women's perception of vulnerability is often developed from the 'lived experience' of cancer and through strong identification with an affected or deceased mother or sister," she says.

New work at the Genesis Prevention Centre, the only UK charity dedicated entirely to preventing breast cancer, will change the way risk is assessed, says Gareth Evans, a professor of genetics who heads the research. "More than a few boxes being ticked, we will take into account the whole picture of the individual woman: when her periods started, when she had children, if she took the Pill, lifestyle factors, family members who've had cancer," he says. "This will give us and the women a much better picture of breast cancer risk. We have to do something to tackle the kind of dread that has made a few women that I know decide to have risk-reducing mastectomy, despite being moderate risk, because they didn't want to go through what their mother or sister had gone through."

What is genetic testing?

* The analysis of the DNA (genetic code) contained in a few drops of blood is an expensive, time-consuming process. Only a few of the genes implicated in hereditary cancer have been found. If a person is born with a gene mutation that makes them more likely to develop cancer, they have an inherited cancer gene.

* There are two types of genetic change or mutation: those that are passed down from generation to generation (germline mutations); and those that happen during a lifetime and are not passed on (somatic mutations).

* Some things about us are the outcome of several genes and our environment interacting together. For example, a person's weight and height are linked to the genes they have inherited (someone with tall parents is likely to be tall) but also to diet, exercise, childhood illnesses and so on. It seems that cancer, even if there is a strong family history, is almost always the outcome of an interaction between genes and the environment.

* Age is the greatest risk for getting cancer. There is nothing you can do about that, but you might be able to improve your chances of not getting cancer by giving up smoking, staying slim, having a healthy diet and not drinking.

* The European Code Against Cancer recommends that you should contact your doctor if you have display any of the following symptoms: a lump anywhere in your body; changes in the shape, size or colour of a mole; a cough or hoarseness that won't go away, especially after a number of weeks; a change in bowel movements that doesn't go away after two weeks; any abnormal bleeding; unexplained weight loss.

www.macmillan.org.uk www.cancerbackup.org.ukwww.genesisuk.org