This study will investigate photoacoustic tissue characteristics of breast lesions both at diagnosis, and within a separate subgroup of patients, physiological changes in breast tumors during neoadjuvant chemotherapy (NAC). Our objective in this pilot study will be to identify PA parameters that can distinguish benign vs. malignant lesions, and also, if PA parameters change with within breast tumors during chemotherapy treatment over time. Our hope is to use this information to correlate with pathological response.

