Breast tomosynthesis for the clarification of mammographic BI-RADS 3 lesions can decrease follow-up examinations and enables immediate cancer diagnosis

Abstract

Background The limited sensitivity of mammography in case of a high breast density often produces unclear or false-positive findings, so-called BI-RADS 3 lesions, which have to be followed up to prove benignity. Digital breast tomosynthesis (DBT) was developed to reduce such summation effects. Purpose To evaluate the influence of an additional DBT on the management of mammographic BI-RADS 3 findings and whether DBT can decrease the time to definitive diagnosis or not. Material and Methods We analyzed 87 patients with a mammographic non-calcified BI-RADS 3 lesion who underwent an additional DBT of the affected breast. A follow-up two-dimensional (2D) examination or a histological result of the lesion had to be available. The images were analyzed especially for the BI-RADS category and incremental diagnostic accuracy. Moreover, the inter-reader reliability and the radiation dose were evaluated. Results The BI-RADS category has been changed by the addition of DBT: 57.1% were assessed as BI-RADS 1 or 2, 4.6% as BI-RADS 4, and only 38.3% remained as BI-RADS 3. The intraclass correlation coefficient for the three readers showed a good agreement for inter-reader reliability. No false-negative examination was found in the follow-ups. Nine lesions were biopsied (seven benign, two malignant). Both malignant lesions were suspicious in the DBT (BI-RADS 4). A significant higher glandular dose was necessary for the DBT. Conclusion DBT has the potential to reduce the recall-rate of BI-RADS 3 lesions and to find and diagnose malignant lesions earlier than 2D mammography alone.