A team of researchers at the University of Sydney has conducted a study of advanced mammography technology – including 3D scans – finding promise in future screening methods but cautioning it is too early to make definite conclusions about effectiveness.
The pilot study, the results of which were published in the Medical Journal of Australia, comprised thousands of mammography screenings of women across the country, and compared the results 2D screenings with 3D mammography technology, known as tomosynthesis.
The advantage of tomosynthesis compared to conventional or 2D mammography, is that it can overlapping or superimposed breast tissue, which can cause problems during 2D scans, explained research leader Nehmat Houssami, a professor of public health and National Breast Cancer Foundation Research Leadership Fellow at the university's Faculty of Medicine and Health.
"By problems I mean it can hide a small cancer or can create 'lesions' from normal tissue structures, so 3D can help improve interpretation of the imaging: it tends to improve cancer detection or it can reduce false-positive screening results, but the findings have varied between studies," she said.
Houssami noted the breast cancer research program she leads at the School of Public Health has been focusing on applied research using tomosynthesis for early detection.
"We have done Australia's first trial of the technology in a real-world population screening program, and we have also collaborated with screening programs in both Italy and in Norway to undertake large trials of tomosynthesis in screening which have provided data on how the technology performs compared to standard mammography," she said.
With regard to technologies like data analytics, artificial intelligence and machine learning that will be needed to make the most of 3D mammogram technology, Houssami said when it comes the screen-reading time, the longer time taken to interpret 3D (compared to 2D) could mean that AI solutions might be needed.
"It is important to note that we do not yet have evidence on the longer-term health outcomes for 3D versus 2D screening, and this will be very important to do in future research," she said.
From a technical development perspective, there are a number of issues and challenges for 3D mammography implementation for population screening, including how to limit or reduce the radiation dose and the aforementioned screening-reading time.
Other challenges include improving the logistics of imaging workflow and viewing and archiving, as the required IT infrastructure is greater for 3D than 2D imaging.
"These are issues that could cause implementation challenges for screening programs wanting to use 3D as a primary screening test," Houssami noted.