Breast density matters

European experts now recommend that breast density be reported with every mammogram and that women with extremely dense breasts be advised to undergo additional screening, given their greater risk of breast cancer.

Breast density refers to the appearance of breast tissue in a mammogram. High breast density can mask signs of breast cancer in mammograms; dense breast tissue appears white, as does breast cancer. High breast density is also, in itself, a risk factor for breast cancer. Your breasts could lie anywhere along a spectrum from low to high density. The radiologists who examine your mammogram can tell how dense your breasts are, but this information is not currently routinely shared with women in New Zealand. Women with extremely dense breasts are at greater risk of breast cancer than those with low or average density. Ultrasound or MRI, in addition to mammograms, can improve detection of breast cancer in dense breasts.  Breast imaging experts in Europe and the US now recommend that women be advised of their density and counselled to undertake extra screening.

New recommendations from the European Society of Breast Imaging (EUSOBI) were published this month. Recent research results provide compelling evidence that contrast-enhanced MRI is cost-effective and can reduce breast cancer mortality in women with extremely dense breasts. EUSOBI recommends that women should be informed about their breast density and calls on all providers of mammography screening to share density information with all women. EUSOBI recommends that women aged 50-70 years with extremely dense breasts be offered screening breast MRI every 2 to 4 years. The article can be seen here.

BCAC has discussed the need for measurement and reporting of breast density with the National Screening Unit (NSU) and BreastScreen Aotearoa (BSA) for several years now. BCAC’s Fay Sowerby contacted Mr Adam Stewart, BSA clinical director, to hear his reaction to the European announcement. He noted that “EUSOBI have had a major shift in policy” and told her that “We continue to have this topic on our workplan, currently de-prioritised due to Covid/Omicron.  We are currently in active discussions with international experts including in Western Australia”.  (Western Australian breast screening providers have been advising women of their density for many years.) 

BCAC is aware that some private breast clinics in New Zealand do report breast density and recommend annual ultrasound and mammography to those women with extremely dense breasts. BCAC suggests that NZ women ask directly about their breast density when they have their next mammogram, to raise awareness of this issue and to gain useful information for making their own decisions about breast cancer screening.

16th March 2022

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