Lymphovascular Invasion in BRCA Related Breast Cancer Compared to Sporadic Controls.

Abstract

Abstract Background: Germline mutations in the BRCA1 and BRCA2 genes predispose to the development of breast cancer, exhibiting a specific histological phenotype. Identification of possible hallmarks of these tumours serves several purposes. Biomarkers can contribute to the selection of high-risk patients for genetic screening, help to identify the pathogenicity of so called “unclassified variant” mutations, and insight in the carcinogenetic pathways allows to develop new targeted therapies. Since BRCA1-associated breast cancers have pushing borders that prevent them from easily reaching vessels, and are often of the medullary (like) type that has a low rate of lymphovascular invasion (LVI), we hypothesized that absence of LVI could characterize BRCA1 related breast cancer.Methods: A population of 68 BRCA1 and 10 BRCA2 related invasive breast cancers was evaluated for LVI by an experienced breast pathologist blinded to mutation status, and compared to a control group matched for age, grade and tumour type.Results: LVI was present in 25.0% of BRCA1 related cases, compared to 20.6% of controls (P=0.54, OR=1.29, CI 0.58-2.78). No significant differences were found for the BRCA2 group either (P=1).Conclusion: LVI seems to occur as much in BRCA1 germline mutation related breast cancers as in sporadic controls. Apparently, these hereditary cancers find their way to the blood and lymph vessels despite their well demarcation and often medullary differentiation, indicating that these cancers may have specific vasculoinvasive properties. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6019.