The significance of circumscribed malignant mammographic masses in the surveillance of BRCA 1/2 gene mutation carriers.

Breast cancers in gene mutation carriers may escape mammographic detection because of rapid growth and tumor expansion. Therefore, they may mimic benign lesions on the mammogram. Twenty-nine BRCA 1/2 mutation carriers under surveillance developed 31 breast cancers between 1994 and 2001 at a mean age of 44.2 years. Controls were 63 women with 67 breast cancers in the same period at a mean age of 53.8 years, also under surveillance because of a life time risk of at least 15%. In 26% of the carriers vs. 48% of the controls, mammography was the method that first suspected a malignancy. Seven radiologists performed a retrospective review of the original mammograms to establish technical assessment, with special attention for circumscribed lesions and estimated probability of malignancy. In the mutation carriers seven (23%) circumscribed non-calcified mammographic masses were found and three in the controls (4.5%) P=0.01. These masses were proven to be malignant. In both groups around 70% of these fast-growing circumscribed lesions were detected by the patients. The masses were situated in breasts with a good interpretable breast pattern. BRCA 1/2 mutation carriers had a significantly higher percentage of circumscribed non-calcified mammographic masses that proved to be malignant. These mammographic lesions in women at high risk should be described as at least Birads 0 and worked-up with ultrasound and needle biopsy.