Research begins to better understand link between early-life body size and pre-menopausal breast cancer

Murdoch Children’s Research Institute researcher Professor Terry Dwyer has received a grant to better understand the link between body mass index (BMI) and pre-menopausal breast cancer.  

Professor Dwyer was awarded the £550,000 World Cancer Research Fund grant to explore how low childhood weight increases the risk of developing breast cancer later in life and to determine if larger body mass in childhood and adolescence could provide protection against it. 

Around 30 per cent of women with breast cancer are diagnosed before they go through menopause. Pre-menopausal breast cancer, or early-onset breast cancer, is often more advanced when it is diagnosed, more aggressive and harder to treat than breast cancer that begins at an older age.

Following on from research published in the New England Journal of Medicine, this study will analyse data and biospecimens from the International Childhood Cardiovascular Cohorts (i3C) Consortium that can be linked to adult cancer outcomes.

Professor Dwyer said the study was the first of its kind in this population and would bring together long-term data, along with 40-year follow-up, on lifestyle and body measurements in childhood.  

“There is considerable evidence that body mass index is related to the risk of pre-menopausal breast cancer, but the possible reasons for this have not yet been well explored,” Professor Dwyer said.

“It’s unclear why low BMI, in this case, leads to an increased risk of cancer compared to other cancers, such as colorectal cancer, which are linked to a higher BMI; however, we’ve found that a higher ratio of ductal breast tissue to fat tissue is positively related to risk of pre-menopausal cancer.”

Using information from around 6,000 girls in the 13C cohort, including height, weight, waist size, upper arm size and skin folds, Professor Dwyer will look also look at genetic, metabolic and hormone measurements to explore possible relationships.

Professor Dwyer said while obesity was a known risk factor for several adult cancers, specific childhood risks of being over- or underweight were not well understood because of limited long-term study evidence.

“Determining how childhood obesity contributes to cancer is particularly important for pre-menopausal breast cancer because of the surprising findings based on adults’ recall of their height and weight from childhood that shows underweight girls have a higher risk,” he said.

Professor Dwyer said he hoped the study would help provide preventative measures for children in the future.

“If we show that a higher BMI could prevent pre-menopausal cancer, this should be addressed as part of public health programs to combat childhood obesity.”

Research will be undertaken at Murdoch Children’s over four years, with GenV providing evidence on the development of body mass from birth to adolescence, which will offer deeper insights into this research. Laboratory analysis will be conducted at the International Agency for Research on Cancer.

Learn more about Professor Dwyer's research. 

Funding

Funding is provided by World Cancer Research Fund and World Cancer Research Fund International.