Breast Density & Cancer Risk: Jean Hailes
There is growing evidence for breast density measurement to be incorporated into the national free screening program for breast cancer in Australia.
Breast density is considered to be one of the strongest predictors of breast cancer risk – possibly even a greater risk factor than carrying the BRCA1/BRCA2 gene mutation, which is commonly associated with high breast cancer risk.
Breast density, also called mammographic density, describes the different types of breast tissue detected in a mammogram. High breast density refers to a greater amount of glandular and connective tissues compared to fat, while low density means there is a higher percentage of fatty tissue. Research suggests that about 40% of women aged in their 50s have dense breasts.
A review by Curtin University and the University of Western Australia, recently published in the journal Climacteric, examined the potential for breast density measurement to be incorporated into screening for breast cancer in Australia.
The Royal Australian and New Zealand College of Radiologists recommends density be mentioned on mammogram reports. However, Western Australia is currently the only Australian state that advises women of their breast density through the Federal government-funded BreastScreen mammogram program. Breast density and more detailed 3D mammograms can be provided by private radiologists, who charge out-of-pocket fees to patients.
Jean Hailes endocrinologist Dr Sonia Davison says that while the current BreastScreen program has been highly effective in detecting and treating breast cancer, the review reinforces the need for breast density to be incorporated in to the screening process.
“Understanding breast density is important for determining breast cancer risk,” Dr Davison says. “Incorporating this information into a mammogram report can give clinicians further valuable information in terms of assessing an individual’s breast cancer risk.”
In addition to high breast density, a woman’s risk of breast cancer is also influenced by age, family history, being overweight, alcohol consumption, and other lifestyle factors.
The Federal Government has agreed to review the growing evidence about the importance of breast density, with a view to updating BreastScreen Australia’s position. It is likely to make a decision by mid-2018.
Breast density is not based on size, shape, firmness or lumpiness, and can only be detected by mammogram. Dense tissue appears white on a mammogram – as do tumours or other abnormalities.
So breast density measurement could be a useful predictor of ‘masking’, in which dense breasts may mask tumours. This information could help to determine whether women need additional screening, such as ultrasounds and magnetic resonance imaging (MRI).
Although there are multiple methods used to determine breast density, the review noted that it is as yet unclear which method provides the strongest predictor of breast cancer risk. In addition, because there are no guidelines on how to use breast density data, there is conjecture as to whether knowledge of breast density will help or hinder screening.
“As highlighted in the review, there is not yet a ‘gold standard’ method of determining breast density, and this needs to be addressed,” says Dr Davison.
“Further research is also required to address the potential primary prevention options for women with dense breasts.”
For more information regarding breast density, visit Pink Hope’s newest hub www.bedenseaware.com or speak to your local GP about whether further screening might be right for you.
The original article can be found at https://jeanhailes.org.au/news/breast-density-and-cancer-risk