Short interval follow-up after a benign concordant MR-guided vacuum assisted breast biopsy - Is it worthwhile?

Objective: To determine the utility of short-interval follow-up after benign concordant MRI-guided breast biopsy. Materials and methods: Institutional review board approved, retrospective review of consecutive biopsies performed over 3 years (2007-10) yielded 170 women with 188 lesions that were considered benign concordant. Indication for original study, biopsy results, follow-up recommendations, compliance and outcomes of subsequent MRI and mammography examinations were reviewed. Results: The most common indication for breast MRI was high-risk screening 119/170 (70%). Overall, 59% of lesions (113/188) had follow-up MRI. Of those lesions (n=113), 43% (49/113) presented within 7 months, 26% (29/113) presented within 8-13 months, 11.5% (13/113) presented within 14-22 months, and 19% (22/113) presented after 23 months. At initial follow-up, 37% of lesions were stable and 61% were decreased in size. Three lesions were recommended for excision based on follow-up imaging with one malignancy diagnosed 2 years following biopsy. One additional patient had MRI-detected bilateral cancers remote from the biopsy site 3 years after biopsy. Conclusion: Overall cancer yield of lesions with follow-up MRI was 0.9% (1/113); no cancers were detected at 6 months. Our data suggests that 6-month follow-up may not be required and that annual screening MRI would be acceptable to maintain a reasonable cancer detection rate. Key Points: • Follow-up recommendations after benign concordant MRI-guided breast biopsy remain controversial. • Cancer detection rate was 0.9% overall with no cancers detected at 6 months. • Short-interval follow-up after benign concordant MRI-guided breast biopsy may not be necessary.