Only one per cent of women know that older women - those 80 or older - have the greatest risk of developing breast cancer according to new research published today.
Worryingly, the research also found that 56 per cent of women wrongly believed that age does not affect breast cancer risk.
The strongest risk factor for breast cancer - after gender -is age. The older the woman, the higher her risk. About one in 70 women will develop breast cancer between 40 and 50 years old but for women from 80 to 90 the figure 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.
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 researchers think are contributing to the confusion over breast cancer risk.
Researchers fear the misunderstanding about breast cancer risk could be putting women's health in jeopardy. If women think they are at low risk they 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.
Kath Moser, consultant researcher at Cancer Research UK's Cancer Epidemiology Unit in Oxford 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, 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."
Source: Cancer Research UK