Current referral rules used by family doctors in England to identify younger women at higher risk of breast cancer could be overlooking up to 95% of those who will develop the disease within the next decade, according to research published in the British Journal of Cancer, raising questions over whether risk assessment should extend beyond family history alone.

The study, led by researchers at the University of Cambridge and The Institute of Cancer Research, London, compared the National Institute for Health and Care Excellence (NICE) referral criteria with BOADICEA, a risk prediction tool that combines family history with inherited genetic information, reproductive history and lifestyle factors. The researchers analysed data from 1,258 women under 50 enrolled in the Breast Cancer Now Generations Study between 2004 and 2011.

Under current NICE guidance, only 1.4% of women would have been referred for specialist assessment, identifying just 4.4% of those who went on to develop breast cancer within 10 years. Using the full BOADICEA model, 26.5% of women would have been classified as having above-average risk, capturing 34.8% of future breast cancer cases.

The findings highlight a major weakness in relying largely on family history. Researchers found that 73% of women under 50 who later developed breast cancer had no known family history of the disease.

"We need to get better at identifying women at highest risk of breast cancer so that we can intervene early, when there are more options for treating, or even preventing, their disease," said senior author Dr Juliet Usher-Smith of the University of Cambridge. "It's time to look again at these criteria in the light of our findings."

Breast cancer is the world's most commonly diagnosed cancer and accounts for about one in four cancers in women. Detecting those at higher risk before symptoms appear can allow for closer surveillance, preventive medicines, or, in selected cases, surgery to reduce risk.

The results support growing evidence that multifactorial risk models outperform family history alone. Previous studies, including research underpinning the BOADICEA model and other international risk prediction tools, have reported improved identification of women at elevated risk. However, experts caution that no model can predict every future cancer, and wider use of genetic testing may increase false-positive referrals, healthcare costs and patient anxiety.

Professor Montserrat Garcia-Closas of the Institute of Cancer Research said any policy change would require balancing improved detection against practical demands on NHS staffing and diagnostic services. Breast Cancer Now and Cancer Research UK, which supported the research, said the findings should inform NICE's ongoing review of its family history guidance while ensuring that any future programme remains equitable and adequately funded.

Researchers are now evaluating whether comprehensive risk assessment can be introduced safely, fairly and cost-effectively in routine primary care before any changes to national practice are considered.