A study has found that genetic and molecular analysis of individual breast tumours could help predict the likelihood of a woman’s disease coming back after treatment and in what time frame.

The study, led by scientists at the Cancer Research UK Cambridge Institute at the University of Cambridge, examined the patterns of genetic changes within tumours from nearly 2,000 women with breast cancer by combining IntClust (a classification of 10 different subgroups with distinct molecular profiles) with factors known to influence breast cancer survival such as age, tumour grade and size and the number of lymph nodes affected.

They then followed their progress over 20 years – including whether their cancer returned. They used this information to create a statistical tool that can better predict if, and when a women’s breast cancer could come back.

Off the back of the study, researchers are working on a routine test that could one day help doctors offer women a more accurate prediction of if, and when, their disease may return. Although not available to patients yet, this means that in the future, treatments and follow-up can be tailored, improving women’s chances of survival.

“These exciting findings could offer another step forward in the way we classify and treat breast cancers," said Dr Simon Vincent, director of research at Breast Cancer Now.

"We hope these 11 molecular subtypes could in future help us better predict long-term outcomes and lead to more personalised treatment plans for patients based on the properties of their tumour. For example, if we could identify patients with hormone-positive breast cancer at greater risk of recurrence twenty years after their treatment, we may be able to offer them prolonged hormone therapy or other long-term interventions to reduce this risk.

“Crucially, this major study could help us tease apart the diverse set of hard-to-treat breast cancers currently grouped together as ‘triple negative’, and identify certain patients that are unlikely to experience a recurrence more than five years after their treatment.”

They also identified subgroups of women with oestrogen receptor-positive (ER+) tumours, who were at a higher risk of their cancer coming back up to 20 years after they were first diagnosed.

Around 12,300 women in the UK could belong to one of these late relapse subgroups and therefore might benefit from longer courses of treatments such as tamoxifen, or more frequent check-ups.