Breast Implants and Breast Cancer — Reanalysis of a Linkage Study

Abstract
In 1992, Berkel and colleagues reported in the Journal the results of their study of the potential association of breast augmentation and breast cancer. The study reported that women who had breast augmentation had a significantly lower subsequent risk of breast cancer (P<0.01) than the general population, with a standardized incidence ratio of 0.48 overall. Assuming a 10-year induction period (that is, assuming that cancers found within 10 years of the augmentation might have been the result of a process begun before surgery and therefore should not be considered), the reported standardized incidence ratio was 0.16. Problems were later identified involving some of the study methods. This paper reports a second analysis of these data.