Breast MRI Screening of Women with a Prior High-Risk Lesion: Preliminary Results.

Abstract

Abstract Purpose: To determine the frequency of breast cancer detection in women at increased risk due to a prior high-risk lesion.Materials and methods: An IRB approved retrospective review was performed of the records of 2184 breast MRIs starting from 1999, to identify patients who commenced screening breast MRI who had a history of a prior high risk lesion. Eighty-three women were identified who had a prior biopsy demonstrating a high-risk lesion such as atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS). History, imaging, and pathologic findings were reviewed.Results: Histologies of prior high-risk lesions in these 83 women were ADH in 24, LCIS in 54 and ALH in 5. The median length of MRI follow-up was four (range, 1-9) years. Biopsies were recommended based on MRI findings in 39 (47%) of 83 women, yielding cancer in seven (8%) women (four of whom also had benign biopsies), and benign findings only in 32 (39%) women. Six of the seven women who developed a breast cancer also had a family history of breast cancer. Histologic findings in these seven cancers were ductal carcinoma in situ (DCIS) in 4 (57%) and invasive cancer in three (43%). Invasive cancer histologies (n=3) were ductal in one and lobular in two; maximal histologic size was 2.0 cm. This large invasive cancer had a mammographic, sonographic, and palpable correlate, and was node-positive; the other cancers were identified by MRI only. Among these seven cancers, two (29%) were detected in screening year 1, two (29%) in screening year 2, two (29%) in screening year 3 and one in screening year 4 (14%). Three (43%) of the seven cancers were in the contralateral breast. In these 83 women, the likelihood of detecting cancer by MRI was higher in those with, rather than without, a family history of breast cancer (6/54=11% vs. 1/29=3%) and in women with prior LCIS rather than prior ADH (6/54=11% vs. 1/24=4%).Conclusion: Breast MRI detected cancer in 7 (8%) of 83 women with a prior high-risk lesion, six (86%) of whom also had a family history of breast cancer. Among these cancers, all were detected during the first four years of screening and less than half were invasive (43%). Further work with more patients is needed to determine the utility of breast MRI screening in women with specific prior high-risk lesions, with and without additional risk factors. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4002.