 Phase C enrollment will include 5 patients per surgeon, with 2-3 surgeons per site and up to 11 sites. The assessment for completing the training will be done in collaboration between Lumicell and each surgeon and will be documented. Subjects undergoing a lumpectomy procedure to treat primary breast cancer will be injected with a single dose of LUM015 4 2 hours prior to surgery at a dose of 1.0 mgkg. The sequence of events during the surgical procedure will vary based on the standard of care used by the surgeon. Patients will receive at a minimum the standard of care practices for each site. Lumicell-guided shaved cavity margins will be removed only after the surgeon has attempted to remove the main specimen with grossly negative margins. After Lumicell-guided therapeutic shaves are removed, the surgeon will continue to perform the lumpectomy procedure according to his or her institutions standard of care practice. 