Additional value of US to mammography: profit and loss

Abstract

To determine the additional value of US to mammograpln in benign and malignant breast pathology three observers scored on a five-point scale the mammograms retrospectively of 18 1 breast lesions consisting of 58 benion cystic lesions, 48 solid benign lesions and 75 malignant lesions. Subsequently, the sono,,rams were added and a second score followed. The scores were compared with the final diagnosis. Receiver-operating characteristics (ROCS) and x values for interobserrver variability were calculated, and with the differences between the mammogram scores and the sonogram scores a “profit-and-loss account” was designed. The ROCS showed the best performance after adding the sonograms, but the difference was not significant. On the basis of the profit-and-loss account the diagnostic performance could be analysed as profit in improved detection and loss in a downswing. In the category of benign cystic lesions the profit of US was 14.2 % and the loss was 1.1 %. In the category of benign solid lesions the profit was 1.3 % Because of an increase in false-positive malignant diagnoses US led to a loss of 10.1 % In the malignant lesions US led to a profit of 10.2% and a loss of 0.8 % In conclusion. US acids valuable additional information to the diagnosis of malignancies, but is a source of confusion in benign solid lesions. Its unreliability in the differentiation between solid benign and malignant lesions necessitates systematic application of fine-needle-aspiration cytology as a reliable diagnostic procedure in breast lesions.