Cancers Missed on Mammography

Observer error in reading screening mammograms has been identified as a significant factor in delayed diagnosis of breast cancer. The magnitude of the problem is estimated to be about 30 of potentially detectable cancers are overlooked for one or more years before detection. Computer-aided diagnosis CAD programs have been developed to aid radiologists in the detection task, and pre-clinical studies have shown that CAD applied to digitized mammography films can flag about 50 of radiologists observational oversights. Preliminary study has also shown a wide variability in radiologist observer performance. The purpose of this investigation is to test how many additional cancers are detected by radiologists using CAD, in an observer study using an enriched mixture of cancers 400 cases, with benign to malignant ratio 31. Based on previous work, the expectation is that average cancer detection will improve about 15 with the use of CAD, similar to what has been shown when two human observers double reading read the same cases. The phases of the project include collection of case material MISSED CANCERS AND NORMALS, characterization and digitization of the films, running the CAD programs, performance of the observer study, and analysis of the results.