Low Dose Molecular Breast Imaging as a Screening Tool for Women With Dense Breasts

A new test for breast cancer screening, molecular breast imaging (MBI) may be more sensitive than mammography for detecting breast cancer in women with dense breasts. The purpose of this study is to see if MBI using a low dose of gamma radiation can find cancers not seen on mammography. Hypotheses: 1. Low-Dose MBI has a significantly higher sensitivity and specificity and equal or higher positive predictive value than SM in women age 40 and older with mammographically dense breasts. 2. Low-dose MBI has comparable sensitivity and specificity to that previously achieved with MBI using a higher dose of radiation. 3. MBI produces a low false positive rate (specificity \>90%) that permits its use as a screening tool in this patient population.