Statement: the secondary trial and the primary trial both used MRI and Letrozole for their interventions.
Primary_evidence: INTERVENTION 1:    Letrozole, Breast Enhancement, Safety   Single arm of healthy postmenopausal women to have two breast MRI (baseline and post-treatment). Letrozole of 12.5 mg/day is given for three successive days just prior to the second MRI.
Secondary_evidence: INTERVENTION 1:    Healthy Volunteers   Healthy women will be screened for Magnetic Resonance Imaging (MRI) contraindications, and then undergo contrast injection, and SWIFT acquisition.   Magnetic resonance imaging: Patients and healthy volunteers will be first screened for MRI contraindications. The SWIFT MRI workflow will be performed as follows:   an IV line is placed by nurse,   patient is placed in the 4 T MRI scanner at CMRR,   initial scout images and manual linear shims are adjusted,   Pre-contrast SWIFT T1 weighted images and T1 map are obtained,   continuous SWIFT acquisition begins immediately before contrast injection,   contrast injection,   continuous SWIFT acquisition continues for 12 min after contrast,   late enhancement images may also be obtained.   10 and 30 patients will be scanned in the first and second year, respectively. Thresholds will be set for prospective analysis. SWIFT-DCE diagnostic performance will be compared to prior FLASH-DCE methods. INTERVENTION 2:    Breast Cancer Patients   Breast cancer patients who have suspected breast lesion that will be biopsied will be screened for Magnetic Resonance Imaging (MRI) contraindications, and then undergo contrast injection and SWIFT acquisition.   Magnetic resonance imaging: Patients and healthy volunteers will be first screened for MRI contraindications. The SWIFT MRI workflow will be performed as follows:   an IV line is placed by nurse,   patient is placed in the 4 T MRI scanner at CMRR,   initial scout images and manual linear shims are adjusted,   Pre-contrast SWIFT T1 weighted images and T1 map are obtained,   continuous SWIFT acquisition begins immediately before contrast injection,   contrast injection,   continuous SWIFT acquisition continues for 12 min after contrast,   late enhancement images may also be obtained.   10 and 30 patients will be scanned in the first and second year, respectively. Thresholds will be set for prospective analysis. SWIFT-DCE diagnostic performance will be compar