Imaging tech could give better breast cancer risk estimation
Women with ‘dense’ breast tissue – which are the areas that show up as white on the mammogram – have a considerably higher risk of developing the cancer compared to those with less density, in a little understood area being investigated by TRI-based QUT researchers.
Women with high breast density are more likely to have cancers missed on their mammogram, and while regular mammograms are instrumental in boosting breast cancer survival rates, new research shows breast density also has an impact on the accuracy of mammography.
The QUT research team hopes their work in a new imaging technology will boost awareness of breast density as a risk factor, and the accuracy of their mammograms.
Study lead authors Dr Konstantin Momot and Professor Rik Thompson initially found that a portable nuclear magnetic resonance (NMR) machine could more precisely measure breast density, than current technology. They previously published this using laboratory samples, and now have shown it in 15 healthy women volunteers.
The volunteers underwent an imaging routine consisting of 2D X-ray mammography, 3D compositional breast imaging with MRI, and 1D compositional depth profiling of the right breast using the portable NMR.
Until now, breast density could only be measured by having a mammogram. While breast density decreases with age, mammography isn’t often used on young women because their breasts tend to be very dense, and to reduce accumulated exposure to radiation.
“The portable NMR gives us a two-dimensional image of what’s inside the breast tissue, the density, which ultimately allows women to better gauge their overall risk early,” Professor Thompson said.
“Breast cancer risk algorithms are more accurate when breast density is added into the mix, and we have found a way to measure this in all women, including younger women under 50.
“Our instrument works by giving you a profile of density from the skin for about two-and- a-half centimetres into the tissue.
“We’re essentially obtaining mammographic density score without using x-rays, so women aren’t exposed to them. The technology is portable and relatively inexpensive.”
Most breast cancers are found in women who are 50 years old or above. Being female, increasing age, family history and high oestrogen levels, which are affected by the number of breast-fed children and age at first menstrual period, are a few of the disease’s big risk factors.
“Although breast density is a known risk factor for breast cancer, it is not yet measured for this reason only,” Dr Momot said.
“Our knowledge of breast density comes anecdotally from all the breast cancer screening that has been done over the decades.
“Not all women have mammograms, so as we progress towards wanting to know breast density status more generally, our portable NMR could help fill this gap.
“The new imaging technique could benefit younger women with high mammographic density and those living in remote areas, far from major hospitals.”
Professor Thompson added, “once further optimised and developed, the portable NMR could be used in measuring breast density in young women where mammography isn’t recommended.
“As some women need to avoid x-rays due to a genetic syndrome that makes them extra sensitive to x-ray damage, so we can also assess their breast density / breast cancer risk too.
“Also, the portable NMR can be used to potentially monitor women undergoing hormonal therapy for breast cancer, where reduction in mammographic density as early as three months after starting, may give an indication of how quickly and effectively the treatment is working.
“These indicators eventually could lead to a therapy change or something more effective to avoid unnecessary side effects.”
The NMR technology could be cheaper than mammography machines already available, but Professor Thompson notes more research, and optimisation of the technology, is needed.
“We want to get an empirical estimate of the breast density of a woman and to monitor it over time. This would help to understand the relationship with oestrogen, a driver for mammographic density, and lifestyle factors,” he said.
The study also found that there is scope for further development of portable NMR-based imaging and its physics for potential treatments beyond breast imaging.
The published paper:
Nicholas D McKay-Parry, Tony Blick, Satcha Foongkajornkiat, Thomas Lloyd, Erik W Thompson, Honor J Hugo, Konstantin I Momot. Portable NMR for quantification of breast density in vivo: Proof-of-concept measurements and comparison with quantitative MRI. Magnetic Resonance Imaging, Volume 92, 2022, Pages 212-223, DOI: doi.org/10.1016/j.mri.2022.07.004
