Predictors associated with MRI surveillance screening in women with a personal history of unilateral breast cancer but without a genetic predisposition for future contralateral breast cancer.

Abstract

For women with a personal history of breast cancer (PHBC), no validated mechanisms exist to calculate future contralateral breast cancer (CBC) risk. The Manchester risk stratification guidelines were developed to evaluate CBC risk in women with a PHBC, primarily for surgical decision making. This tool may be informative for the use of MRI screening, as CBC risk is an assumed consideration for high-risk surveillance. Three hundred twenty-two women with a PHBC were treated with unilateral surgery within our multidisciplinary breast clinic. We calculated lifetime CBC risk using the Manchester tool, which incorporates age at diagnosis, family history, genetic mutation status, estrogen receptor positivity, and endocrine therapy use. Univariate and multivariate logistic regression analyses (UVA/MVA) were performed, evaluating whether CBC risk predicted MRI surveillance. For women with invasive disease undergoing MRI surveillance, 66% had low, 23% above-average, and 11% moderate/high risk for CBC. On MVA, previous mammography-occult breast cancer [odds ratio (OR) 18.95, p<0.0001], endocrine therapy use (OR 3.89, p=0.009), dense breast tissue (OR 3.69, p=0.0007), mastectomy versus lumpectomy (OR 3.12, p=0.0041), and CBC risk (OR 3.17 for every 10% increase, p=0.0002) were associated with MRI surveillance. No pathologic factors increasing ipsilateral breast cancer recurrence were significant on MVA. Although CBC risk predicted MRI surveillance, 89% with invasive disease undergoing MRI had <20% calculated CBC risk. Concerns related to future breast cancer detectability (dense breasts and/or previous mammography-occult disease) predominate decision making. Pathologic factors important for determining ipsilateral recurrence risk, aside from age, were not associated with MRI surveillance.