The Ultrasound Study of Tamoxifen

Study Summary

Background: \- Studies have shown that changes in breast density (the amount of white area on a woman's mammogram) may be related to changes in breast cancer risk. Currently, there is no ideal way to measure breast density repeatedly over time. Researchers want to test whether ultrasound tomography scans can show changes in breast density. To examine these changes, healthy volunteers with no history of breast cancer and women who are taking tamoxifen will have ultrasound tomography scans. Objectives: \- To test whether ultrasound tomography scans can show changes in breast density related to tamoxifen exposure. Eligibility: \- Women between 30 and 70 years of age who are (a) taking tamoxifen or (b) healthy volunteers who have never had breast cancer. Design: * All participants will have a screening visit. Healthy volunteers will have one additional study visit; women taking tamoxifen will have three additional study visits. * All participants will be screened with a physical exam and medical history. They will also give blood and saliva samples. This visit will also include an initial ultrasound tomography breast scan. * For the healthy volunteers: * At the study visit (12 months after the screening visit), participants will have a short interview and be weighed. They will also have an ultrasound tomography breast scan and provide a blood sample. * For the women taking tamoxifen: * At the second and third visits (1 to 3 months and 3 to 6 months after starting tamoxifen), participants will have a short interview. They will also be weighed and have an ultrasound tomography breast scan. * At the fourth visit (12 months after starting tamoxifen), participants will have a short interview, weight measurement, and the ultrasound tomography breast scan, and will also provide a blood sample. * All participants may be followed for up to 5 years after their final study visit.