Screening vs staging magnetic resonance imaging-guided core needle breast biopsies: Does MRI indication impact upgrade rate?

Adjunct magnetic resonance imaging (MRI) for both screening high-risk patients and staging for patients with newly diagnosed breast cancer leads to an increased number of biopsies and increased detection of atypical lesions. We assessed whether the malignancy upgrade frequency for high-risk atypia identified via MRI-guided biopsies varied based on indication: high-risk screening vs staging for malignancy. Among 399 MRI-guided biopsies, 46 (11.5%) high-risk lesions (ADH, ALH, and LCIS) were identified. Surgical excision was performed on 37% of 46%, and 24.3% were upgraded to invasive malignancy or DCIS. Of lesions identified by staging MRI, a slightly higher percentage, 28.5%, were upgraded (P = .36). Our data suggest that surgeons should carefully consider excisional biopsy for atypia identified on MRI regardless of indication.