Outcome of Imaging and Biopsy of BI‐RADS Category 3 Lesions

Abstract

Objectives To identify biopsy rates and indications for BI‐RADS 3 lesions in a large cohort of patients and compare with follow‐up compliance and malignancy outcomes. Methods We retrospectively reviewed all BI‐RADS category‐3 lesions seen on mammography and/or ultrasound between 2013 and 2015. Patient age, lesion size, follow‐up rates at 6‐, 12‐, and 24‐months were collected. Biopsy timing, indication, and outcomes (malignant vs benign) were recorded using at least 2‐year follow‐up or biopsy pathology as endpoint. Results Of 2319 BI‐RADS 3 lesions in 2075 women analyzed, biopsy was performed in 173 (7.5%). Most biopsies were performed upfront (99, 57.2%), followed by at 6 (44, 25.4%), 12 (21, 12.1%), and 24‐month follow‐up (9, 5.2%; P < .001). Palpable (P < .001) and larger (median 1.4 vs 1.0 cm, P < .001) lesions in women <40 years (15.2% vs 4.8%, P < .001) were more likely to undergo biopsy. Most biopsies were prompted by patient/physician desire (64.5%, P < .001). Of 783 lesions with available endpoint, 5 (0.6%) were cancer. All cancers were identified either at presentation (in 0–5 months, n = 1) or 6‐month follow‐up (in 5–9 months, n = 4) with biopsy prompted by either morphology change (n = 3) or lesion growth (n = 2). Of the 1855 lesions which were expected for follow up, only 310 (16.7%) underwent all follow‐ups, while 482 (26.1%) had two, 489 (26.5%) one, and 565 (30.6%) had no follow‐up. Conclusions In our cohort, BI‐RADS category 3 lesions had significantly higher biopsy rates compared with the small malignancy rate, all of which were identified at baseline or first follow‐up. Overall patient follow‐up compliance low. Imaging follow‐up, especially at first 6‐month time point, should be encouraged in BI‐RADS 3 lesions, instead of upfront biopsies.