Evaluation of BI-RADS 3 Ultrasound Findings: the Frequency and Incidence of Malignant Lesions, and Tumor Size.

Objective: The aim of the research was to determine the frequency of BI-RADS category 3 findings in ultrasound examinations in relation to the total number of patients, the frequency of malignant lesions, and their average size at the time of detection in BI-RADS 3 ultrasound findings.

Patients and methods: A cross-sectional study was performed on 335 patients (aged 40-75 years) classified in BI-RADS category 3, at the Tuzla Breast Center, University Clinical Center, in the period from March 2017 to November 2020. A total of 13,760 ultrasound examinations were performed, using a Toshiba Xario 100 ultrasound machine with a 12 MHz linear probe. Patients were divided into premenopausal and postmenopausal groups, excluding patients with symptoms and those with previous breast cancer surgery. The images were stored using the Institution's Pictures Activation and Communication System.

Results: BI-RADS category 3 findings accounted for 27% of all ultrasound examinations (N=3.715). Of these, 9.02% (N=335) underwent recommended short-term follow-up. Malignancy was identified in 1.49% of these cases (N=5), with an average tumor size of 13.6 mm at detection. The malignancy rate did not differ significantly between premenopausal and postmenopausal patients (P=0.412). The overall diagnostic yield for malignancy in BI-RADS 3 findings was low, but clinically significant.

Conclusion: While the malignancy rate for BI-RADS category 3 findings is low (1.49%), careful monitoring and adherence to follow-up guideline are essential to balance early detection with avoidance of unnecessary biopsies and associated costs.