Abstract P5-02-06: High-risk lesions diagnosed at MRI-guided vacuum-assisted breast biopsy: Imaging characteristics, outcome of surgical excision or imaging follow-up

Abstract

PURPOSE To evaluate imaging characteristics, outcome of surgical excision or imaging follow-up on high-risk lesions diagnosed at MRI-guided vacuum-assisted breast biopsy (MRI-VAB). MATERIALS AND METHODS We retrospectively reviewed 581 lesions, to include benign, high-risk and malignant lesions, undergoing 9-gauge MRI-VAB from January 2015 to April 2018. We collected patient demographics, risk factors and indications, breast MRI BI-RADS descriptors, histopathological diagnosis at MRI-VAB and surgical excision, frequency of upgrade to malignancy and imaging follow-up of high-risk lesions found in this period. RESULTS 101 patients with 107/581 (18.4% of all lesions) had high risk lesions at MRI-VAB, including atypical ductal hyperplasia (ADH)(n=19/107, 17.8%), lobular neoplasia (n=35/107, 32.7) including atypical lobular hyperplasia (ALH), lobular carcinoma in situ (LCIS), ALH plus LCIS, papillary lesions (n=44/107, 41.1%), radial scar/complex sclerosing lesion (RS/CSL)(n=8/107, 7.5%) and flat epithelial atypia (FEA)(n=1/107, 1%). 71/107 (66.4%) high risk lesions were excised. 16/71 (22.5%) were upgraded to malignancy (4 invasive cancer, 12 DCIS). The upgrade rate for ADH and lobular neoplasia was 5 /16 (31.3%) and 8/26 (30.8%) respectively. The upgrade rate for RS/CSL was 1/6 (16.7%). Of the 22 papillary lesions excised, 2 (9.1%) demonstrated pathologic atypia and were upgraded to DCIS. The other 20 papillary lesions had no upgrade or atypia. Excised high risk lesions showing upgrade varied from 0.4 to 6 cm in length (average 2.1 cm). Increasing size correlated with tendency towards increased upgrade to malignancy, but there were no other specific imaging features to predict malignancy upgrade. CONCLUSION There were no specific MRI imaging characteristics of high-risk lesions to predict malignancy upgrade. Therefore, surgical excision is recommended for high risk lesions especially ADH or lobular neoplasia. Additionally, non-atypical papillomas did not demonstrate malignancy upgrade in our small study. And further larger studies may demonstrate that these lesions may not need to be surgically excised. Citation Format: Okamoto S, Covelli JD, DeMartini WB, Daniel BL, Ikeda DM. High-risk lesions diagnosed at MRI-guided vacuum-assisted breast biopsy: Imaging characteristics, outcome of surgical excision or imaging follow-up [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-02-06.