The investigators hope to prove that radiation and surgical scarring does not result in changes that affect the MBI pattern 6-12 months after completion of treatment.

The study will allow us to evaluate whether surgery and radiation have persistent effects on the breast tissue with regards to whether and how such changes impact MBI images and to determine whether the inflammatory changes due to treatment resolve within 6-12 months of completing treatment.

Inclusion Criteria:

• Women who have planned surgical excision of a lesion or have had a baseline MBI study as part of another MBI research protocol who are within 6-12 months of completing breast surgery who are able and willing to return to Mayo Clinic for a follow up MBI study once the 6-12 month interval is complete.
• Women who plan BCT for a malignant lesion or who are within 6-12 months of completing breast conserving treatment and have had a baseline MBI study as part of another MBI research protocol and are able and willing to return to Mayo Clinic for a follow up MBI study.

Exclusion Criteria:

• Women who do not require surgical excision of a breast lesion or breast conserving treatment for breast cancer.
• Patients undergoing mastectomy.
• Women who are pregnant or lactating.
• Women who are taking hormonal contraception or hormone replacement therapy (vaginal estrogen is permitted), or have used these agents within the previous 3 months.
• Women who have received chemotherapy within the previous 6 months or receive chemotherapy as part of their cancer treatment.
• Men (due to the very low incidence of male breast cancer and the lack of any available data regarding the use of scintimammography or MBI in men).
• Women under the age of 18 years.
• Women unable to sit comfortably during image acquisition.
• Women who are unable to return to Mayo Clinic for a follow up MBI scan 6-12 months after surgical excision or 6-12 months after completing radiation therapy for breast conservation.

Women who are seen in the Mayo Clinic Breast Clinic