Ramifications of screening for breast cancer: 1 in 4 cancers detected by mammography are pseudocancers

EDITOR—In this issue Zackrisson et al report on follow-up data from the Malmo mammographic screening trial and conclude that the rate of overdiagnosis of breast cancer was 10%.1 They do not, however, calculate the risk we believe is most relevant to women considering mammography: What is the chance that a screen detected cancer represents overdiagnosis? After 15 years of follow-up, there were 1320 diagnosed in the screened …