This is a multi-center, randomized, two-arm study designed to measure the effectiveness of the SELENE system in reducing the number of unaddressed positive margins in breast lumpectomy procedures when used in addition to standard intraoperative margin assessment.

Inclusion Criteria:

• Female
• Age 18 years or older
• Patients undergoing elective breast conservation surgery for the treatment of Stage 0-III invasive ductal and/or ductal carcinoma in situ
• May include subjects treated with neo-adjuvant therapy (endocrine and/or chemotherapeutic), but not required for study inclusion
• Ability to understand and the willingness to sign a written informed consent document

Exclusion Criteria:

• Male
• Metastatic cancer (Stage IV)
• Lobular carcinoma as primary diagnosis
• Previous ipsilateral breast surgery for benign or malignant disease within two years (this includes implants and breast augmentation)
• Subjects with multi-centric disease (histologically diagnosed cancer in two different quadrants of the breast), unless resected in a single specimen
• Subjects with bilateral disease (diagnosed cancer in both breasts)
• Participating in any other investigational margin assessment study which can influence collection of valid data under this study
• Use of cryo-assisted localization
• Currently lactating
• Current pregnancy
• Subjects for whom the specimen margins have been destroyed, damaged, or are otherwise not intact prior to imaging (device arm only) imaging

The pathologist at each participating site will be blinded to the study arm to ensure that the pathological assessment is unbiased. Additionally, the subject will be blinded to their randomization until the BREAST-Q questionnaire has been completed.