Characteristics of breast carcinomas missed by screening radiologists.

Abstract

To determine whether breast cancers missed at screening mammography have distinguishing characteristics from those of detected cancers. The mammograms of 146 women with mammographically identifiable breast cancer were viewed independently by two radiologists who were blinded as to whether the cancer had been missed or detected (group 1 lesions, missed cancers; group 2 lesions, detected cancers) at screening. The mammographic lesions were characterized as to location, size, density, type, and visibility on two views. A significant difference between missed and detected cancers was found for diameter (P = .03), number of views (P < .0017), and density (P = .0007). Stepwise multivariable logistic regression showed that density (P = .01) and the number of views (P = .03) but not diameter (P = .27) were independently significant in distinguishing the groups. No statistically significant difference was found between the two groups for lesion type (P = .32 for reader 1 and P = .27 for reader 2) or location (P = .86 for reader 1 and P > .96 for reader 2). Missed cancers were statistically significantly lower in density and more often seen on only one of two views than detected cancers.