Copyright 2008 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2008
Despite the appeal of early detection of breast cancer, uncertainty about the value of mammography continues.1 In this issue of the Archives, Zahl et al2 use a clever study design in an attempt to estimate the value of screening. The initiation of a public screening program in Norway allowed them to compare biopsy-confirmed invasive tumors in women receiving a single mammogram between the ages of 50 and 64 years, with the cumulative number of tumors in a group of women aged 50 to 64 years who had been screened on 3 occasions. Because a variety of risk factors were similar for the 2 groups, the cumulative tumor rate in the multiple screen group was expected to be the same as the rate in the age-matched single screen group. However, the rate in the single screen group was about 22% lower.
Kaplan RM, Porzsolt F. The Natural History of Breast Cancer. Arch Intern Med. 2008;168(21):2302-2303. doi:10.1001/archinte.168.21.2302