New data from a large Swedish study show that mammography screening in women aged 40 to 49 years results in a much greater reduction in mortality from breast cancer than has been previously reported.
“This huge study from Sweden should end any debate” over the benefits of regular mammography screening in this age group, said a leading expert on mammography, Daniel Kopans, MD, professor of radiology at Harvard Medical School in Boston, Massachusetts, who was approached for comment. Beginning mammography at age 50 “has never had any scientific basis and should be dropped,” he said.
The issue leapt into headlines late last year, when the US Preventive Services Task Force (USPSTF) recommended against regular screening mammography in women 40 to 49 years, in direct contrast to the recommendations from other American authorities. At the time, top mammography experts, including Dr. Kopans, expressed outrage at this recommendation, saying that it would lead to lives being lost to breast cancer.
The experts also question the calculation of benefit by the USPSTF, which estimated a 15% reduction in breast cancer mortality from mammography in women 39 to 49 years of age.
The new data from Sweden found a 26% reduction in breast cancer mortality among the women in the 40 to 49 year age group who were invited for screening, and a 29% reduction in those who actually underwent the screening (not all those who were invited participated).
“This is bigger and better than has been seen in other studies,” said Jennifer Obel, MD, from the NorthShore University Health System in Evanston, Illinois.
The new data were outlined by Hakan Jonsson, PhD, associate professor of cancer epidemiology at Umeå University in Sweden, at an American Society of Clinical Oncology (ASCO) presscast for the upcoming Breast Cancer Symposium. The study was published online September 29 in Cancer. Dr. Obel was moderating the presscast, and is on the ASCO Communications Committee.0