This trial studies photoacoustic imaging of the breast in patients with breast cancer and healthy subjects. Dense breasts typically reduce the sensitivity of a mammography and also is associated with a higher risk of breast cancer. Photoacoustic tomography combines light and sound to provide more information about breast tissue.

PRIMARY OBJECTIVES:

I. To identify photoacoustic features of breast malignancy and treatment response

OUTLINE:

Participants undergo photoacoustic imaging of the breast over 30 minutes. At subject's discretion, imaging may repeat for a total of 10 studies, each in a separate day.

Inclusion Criteria:

• Women with clinically suspicious or confirmed breast cancer masses (that have not been surgically removed) and will/have already undergo/undergone breast magnetic resonance imaging (MRI).

Exclusion Criteria:

• Pregnant women (there are no known risks to these procedures, but any unforeseen risks are as yet undetermined, so pregnant women will be excluded by means of a verbal confirmation at time of screening).
• Women who have had breast implants in the previous 6 months.
• Women who have had lumpectomy
• Adults unable to consent.
• Individuals who are not yet adults (infants, children, teenagers).
• Pregnant women.
• Prisoners.
• There is no direct benefit of the study to any subject either non-English or English speaker. To facilitate the consent process, we will exclude non-English speaking subjects.