Study Assesses Impact of Digital Mammography on Breast Cancer Detection and Recall Rates
The shift from film to digital mammography increased the detection of breast cancer overall in the United Kingdom—without increasing the recall rate—according to a study published by Blanks et al in Radiology.
“Image quality with digital mammography is improved over that of screen film mammography,” said radiologist and study coauthor Rosalind M. Given-Wilson, MBBS, from St. George’s University Hospitals NHS Foundation Trust, London. “In particular, digital mammography provides the ability to visualize calcifications and see through denser tissue, and it allows the reader to adjust the image.”
Dr. Given-Wilson and colleagues assessed digital mammography’s impact on cancer detection using data from the 80 facilities of the English National Health Service Breast Cancer Screening Program. The data combined with estimates of digital mammography usage enabled the researchers to measure the effect of digital mammography in 11.3 million screening exams in women between the ages of 45 and 70.
Results
The overall cancer detection rate was 14% (P < .001) greater with digital mammography, with substantially higher detection of grade 1 and grade 2 invasive cancers.
At first screening exams for women aged 45 to 52, digital mammography increased the overall detection rate by 19% (P < .001) and for incident screening episodes in women aged 53–70 years by 13% (P < .001). Importantly, the higher sensitivity of digital mammography did not increase the recall rate.
“This improvement happened in the absence of other changes in the English screening program, such as a change in recall rate or introduction of computer-aided detection, so we can be clear that the increased rate of detection is due to the change in technology,” Dr. Given-Wilson said.
Digital mammography increased the detection of some types of cancers more than others. For instance, digital mammography significantly increased the detection of ductal carcinoma in situ (DCIS) at both first screens and subsequent screens.
“These results confirm that digital mammography is superior to screen film mammography in finding invasive cancers and DCIS,” Dr. Given-Wilson said. “Women are more likely to have a cancer detected with a digital mammogram.”
While digital mammography improved detection of grade 1 and 2 cancers, the researchers found no improvement in the detection of grade 3 invasive cancers.
The researchers are looking at the radiologic features of grade 3 cancers on digital mammography to see if optimizing the image for these lesions can aid detection. They are also studying the relationship between grade 3 cancers and subsequent interval cancers.
Disclosure: The study authors’ full disclosures can be found at pubs.rsna.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
