How reliable is modern breast imaging in differentiating benign from malignant breast lesions in the symptomatic...

To assess the ability of mammography and ultrasound individually and in combination to predict whether a breast abnormality is benign or malignant in patients with symptomatic breast disease.

Patients included were those in whom histological confirmation of the abnormality following surgical excision was available. Mammographic and ultrasound appearances were prospectively classified using a four-point scale (1 = no significant lesion, 2 = benign lesion, 3 = possibly malignant, 4 = probably malignant).

Histological confirmation following surgical excision was available in 559 patients, of which 303 were benign and 256 were malignant. The imaging classification was correlated with histology in these 559 lesions. In predicting final histology, the sensitivity and specificity of mammography alone were 78.9 and 82.7%, respectively, of ultrasound alone were 88.9 and 77.9%, respectively, and of mammography and ultrasound in combination were 94.2 and 67.9%, respectively. Only one patient had both a mammogram and ultrasound reported as normal (category 1 for both tests) in whom subsequent histology revealed a carcinoma (0.4% of all carcinomas).

We found that the extensive use of ultrasound increases the cancer detection rate in this selected population by 14%.