The strongest risk factor for breast cancer (after gender) is age. The older the woman, the higher her risk. The chance of a woman in her 40s developing breast cancer is about one in 70, whereas the risk of a woman in her 80s developing breast cancer is one in 25.

The study, funded by Cancer Research UK and the NHS Breast Screening Programme, surveyed 1,496 women, who were asked ‘when is a woman most likely to get breast cancer?’. Respondents were given a series of ten-year age bands and ‘age doesn’t matter’ from which to select their answer. Of those surveyed, 99 per cent answered incorrectly.

56.2 per cent of respondents said ‘age doesn’t matter’; 9.3 per cent responded that a woman was at highest risk ‘in her 40s’; 21.3 per cent ‘in her 50s’; 6.9 per cent ‘in her 60s’; 1.3 per cent ‘in her 70s’; and a mere 0.7 per cent correctly answered ‘80 and older’. The research was published in the British Journal of General Practice.

An increased media focus on younger women who have been diagnosed with the disease, such as Kylie Minogue, and the fact that women are not routinely invited for breast screening after the age of 70 are two factors the researchers think are contributing to the confusion.

The team, from Cancer Research UK’s Cancer Epidemiology Unit at Oxford University, fear the misunderstanding about breast cancer risk could be putting women’s health in jeopardy: women who wrongly think they are at low risk may delay going to their doctor with symptoms, or even ignore an invitation to attend breast cancer screening.

Early detection through screening saves around 1,400 lives every year in England. Cancers detected in screened women are smaller and are less likely to be treated with mastectomy. Attending screening and reporting any changes as soon as possible offers the best chance of finding breast cancer early.

Women aged between 50 and 70 and registered with a GP are automatically invited every three years. There is no upper age limit for breast screening and women over 70 can make their own appointments by contacting their local breast screening unit.

Kath Moser, consultant researcher at Cancer Research UK’s Cancer Epidemiology Unit at Oxford University and lead author of the research, said: ‘These results offer an insight into what women believe about their breast cancer risk. Unfortunately the reality is very different from what most women believe. Breast cancer risk increases with age and is highest in women over 80.’

Julietta Patnick, director of the NHS Cancer Screening Programmes and co-author of the study, who is also affiliated to the Cancer Epidemiology Unit at Oxford University, said: ‘Confusion over who is most at risk of breast cancer is a real concern. Less than one per cent of those surveyed were aware that women over 80 are most at risk of developing breast cancer. Women need to understand that their risk increases with age. If older women wrongly think they are at a lower risk, they may be less likely to attend screening appointments or even report breast cancer symptoms.

‘The breast screening programme offers regular screening to all women over 50 and I would encourage all those eligible to make an informed choice about attending.’

Professor John Toy, Cancer Research UK’s medical director, said: ‘As the age of a woman increases so, too, her risk of breast cancer increases. These results show a potentially harmful lack of knowledge. This confusion needs to be cleared up so that the older woman doesn’t wrongly assume she is “growing out” of potential trouble.’

‘Through our Reduce the Risk campaign, Cancer Research UK is working hard to raise the awareness of breast cancer risk and to encourage, in particular, older women to attend screening.’ (http://www.reducetherisk.org.uk)

Source: University of Oxford