The influence in BRCA1/2 mutation carriers of the specific histologic features of their breast cancers on the mammographic images.

MMA Tilanus-Linthorst, MDa, LC Verhoog MD b, AI Obdeijn MDc, E Meijers Heiboer MD d, JGM Klijn PhD e, AM Eggermont PhD a, CTM Brekelmans PhD e, Th van der Kwast PhD b.

aDepartment of Surgery b Department of Pathology c Department of Radiology d Department of Medical Oncology e Department of Genetics; Erasmus Medical Centre, Rotterdam, Netherlands

AIM Female carriers of a BRCA1/2 gene mutation develop in 50% breast cancer before the age of 50 years. The histopathologic features differ between breast cancers in BRCA1/2 mutation carriers and sporadic cancers in equally young patients . We investigated whether this causes a different presentation at mammography. METHOD We correlated the mammographic imaging results with the histology of 30 beast cancers in 24 BRCA1/2 mutation carriers and 30 sporadic cancers in 29 patients, matched for age and year of diagnosis. RESULTS Breast cancers of BRCA1/2 mutation carriers showed histologic characteristics known from the literature like significantly higher mitotic counts (p<0.01), a higher score for tubule formation (p= 0.03) and higher grade of DCIS (p=0.04) than controls. The significantly more frequent false negative mammography results in carriers versus controls correlated significantly with a high percentage of " pushing borders " at pathologic review (p= 0.03). Negative mammography results were partly caused by cancers presenting in carriers significantly less as the classic spiculated or ill-defined mass and this correlated significantly with a higher percentage " pushing margins" (p=0.02) and a low score for fibrosis (p=0.01). CONCLUSION The specific histopathology of breast cancer in BRCA1/2 carriers is likely to cause a false negative presentation at mammography.

KEY WORDS: surveillance, false negative mammography.

For more information, contact

Paper presented at the International Symposium on Predictive Oncology and Intervention Strategies; Paris, France; February 9 - 12, 2002; in the section on Molecular Pathology.