Kristin Elias MD, Abstract Co-Author: Nothing to Disclose

Islamiat O. Ego-Osuala MD, Presenter: Nothing to Disclose

Sara Daniel Shaylor MD, Abstract Co-Author: Nothing to Disclose

Marissa Lauren Albert MD, MSc, Abstract Co-Author: Nothing to Disclose

Hildegard B. Toth MD, Abstract Co-Author: Nothing to Disclose

Linda Moy MD, Abstract Co-Author: Nothing to Disclose

The purpose of this study is to evaluate the prevalence and rate of malignancy of BI-RADS category 3 lesions detected on screening ultrasound in average and high risk patients.

IRB approved retrospective review of consecutive technologist performed, hand-held screening ultrasound from 1/11 to 12/12 was performed. Patient characteristics, outcome, mammography results, and follow up of all BI-RADS 3 cases were recorded and evaluated.

116/1937 screening US (6%) performed over a consecutive two year period were interpreted as BI-RADS category 3 with a total of 201 probably benign lesions. 53% of women had no known risk factors for breast cancer. 50% of the women were premenopausal and 78% had mammographically dense breasts. Mammography was performed within 1 month in 84.5% of the cases. 108/116 (93%) US exams with 190 probably benign lesions had mean follow up of 15.7 months, range 5-36 months. On follow up, 141/190 (74.2%) lesions were downgraded to benign due to decrease in size, more definitive benign features, or stability over two years. 43/190 (22.6%) lesions remained stable and probably benign. Biopsy was performed of 6 (3.2%) lesions that demonstrated interval growth or suspicious change. One biopsy was performed due to patient preference. All 7 biopsies were benign with results including cysts, fibrocystic change, or fibroadenoma. Two subsequent malignancies were detected in the contralateral breast on follow up within one year. The index lesions assessed as probably benign remained stable. Of the 108 cases with follow up no BI-RADS 3 lesions were found to be malignant.  

In this study where 53% of women were average risk no subsequent cancers were detected in lesions assessed as probably benign on screening ultrasound.

It is possible that with careful assessment some lesions may be interpreted as benign rather than probably benign in order to decrease unnecessary follow up exams without missing a malignancy, especially in an average risk population.

Elias, K, Ego-Osuala, I, Shaylor, S, Albert, M, Toth, H, Moy, L, Outcomes of Probably Benign Lesions Detected on Screening Ultrasound in Women with Average and High Risk: Are We Recommending Unnecessary Follow Up Exams?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045698.html