Breast cancer detection and tumor characteristics in BRCA1 and BRCA2 mutation carriers

Abstract

Purpose To describe imaging findings, detection rates and tumor characteristics of breast cancers in a large series of patients with BRCA1 and BRCA2 mutations to potentially streamline screening strategies. Methods An IRB-approved, HIPAA-compliant retrospective analysis of 496 BRCA mutation carriers diagnosed with breast carcinoma from 1999-2013 was performed. Institutional database and electronic medical records were reviewed for mammography and MRI imaging. Patient and tumor characteristics including age at diagnosis, tumor histology, grade, receptor and nodal status were recorded. Results Tumors in BRCA1 mutation carriers exhibited significantly higher nuclear and histological grade compared to BRCA2 (p<0.001). Triple-negative tumors were more frequent in BRCA1 mutation carriers, whereas hormone receptor positive tumors were more frequent in BRCA2 mutation carriers (p<0.001). BRCA2 mutation carriers more frequently presented with ductal carcinoma in situ (DCIS) alone 14% (35/246) and cancers more frequently exhibiting calcifications (p<0.001). Mammography detected fewer cancers in BRCA1 mutation carriers compared to BRCA2 (p=0.04): 81% (186/231) BRCA1 vs. 89% (212/237) BRCA2. MRI detected 99% cancers in each group. Mammography detected cancer in two patients with false negative MRI (1 invasive cancer, 1 DCIS). Detection rates on both mammography and MRI did not significantly differ for women over 40 years and women below 40 years. Conclusions Breast cancers in BRCA1 mutation carriers are associated with more aggressive tumor characteristics compared to BRCA2 and are less well seen on mammography. Mammography rarely identified cancers not visible on MRI. Thus, the omission of mammography in BRCA1 mutation carriers screened with MRI can be considered.

Abbreviated MRI of the Breast: Does It Provide Value?

“…Riedl et al demonstrated that MRI in high‐risk patients had a sensitivity of 90%, and almost half of all cancers (45%) in their cohort were detected by MRI only. Similar results were found by Krammer et al…”

“…Riedl et al 49 demonstrated that MRI in high-risk patients had a sensitivity of 90%, and almost half of all cancers (45%) in their cohort were detected by MRI only. Similar results were found by Krammer et al 50 Central to breast cancer detection using DCE-MRI is the combination of morphological features and functional information derived from enhancement kinetics; this need is supported by multiple studies and noted in the revised MR Breast Imaging Reporting and Data System (BI-RADS) lexicon. 51,52 There is consensus that the ideal breast MRI protocol should incorporate both a high spatial and high temporal resolution MRI protocol.…”

Contrast‐enhanced MRI for breast cancer screening

“…As a result, the fraction of women in this population with extremely dense breasts is high. In addition, imaging characteristics of cancers developing in women at very high risk are less specific and may resemble benign lesions . Consequently, mammographic screening in women at increased risk has substantially lower performance than in the average population.…”

Multiparametric MRI model with dynamic contrast‐enhanced and diffusion‐weighted imaging enables breast cancer diagnosis with high accuracy

“…Dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) of the breast is the most sensitive test for breast cancer, with a pooled sensitivity of 93% and outperforms mammography, digital breast tomosynthesis, and ultrasound in women at any given risk of breast cancer . However, due to an overlap of morphologic and kinetic features between benign and malignant lesions, there are limitations in specificity (pooled specificity 71%) leading to unnecessary breast biopsies .…”

“…D ynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of the breast is the most sensitive test for breast cancer, with a pooled sensitivity of 93% and outperforms mammography, digital breast tomosynthesis, and ultrasound in women at any given risk of breast cancer. [1][2][3][4] However, due to an overlap of morphologic and kinetic features between benign and malignant lesions, there are limitations in specificity (pooled specificity 71%) leading to unnecessary breast biopsies. 5,6 To improve specificity, several other MRI techniques such as diffusion-weighted imaging (DWI), proton MR, and phosphorus spectroscopy and sodium imaging have been explored, with DWI having emerged as the most robust and valuable for an improved differentiation of benign and malignant breast lesions.…”