The purpose of this study is to evaluate the performance of FDA-cleared SAVI SCOUT Breast Localization and Surgical Guidance System (SCOUT) over a longer duration prior to surgery. The device is a non-wire system, which uses nonradioactive light-activated radar, to provide breast surgeons with real-time guidance to locate and remove the target lesion in the breast and/or axillary tissue. The SCOUT device standard of care use is placement up to 30 days prior to surgery to assist surgeons in the localization and retrieval of breast/axillary lesions. Routine image-guided methods (Mammography, Ultrasound, and CT) are used. In this study, investigators will assess the longer term placement of the SCOUT device over an extended time (31 - 365 days) in order to address the needs of patients who require neoadjuvant treatment prior to definitive surgery.

The SAVI SCOUT (Cianna Medical, Inc.) surgical guidance system received 510(k) U.S. Food and Drug Administration (FDA) approval in August 2014. This system is used as a standard of care since 2015 in the Memorial Healthcare System (MHS) operating rooms by experienced breast surgeons (over 150 MHS breast cancer patients and over 5,000 U.S. breast cancer patients as of September 2016). In MHS standard of care practice, the device is placed at the target lesion(s) under image-guidance by the radiologist up to 30 days prior to surgery.

Patients with certain types of breast cancer undergo neoadjuvant treatment with biologic (hormonal) and/or chemotherapy with the goal of decreasing the tumor volume prior to definitive surgery. If the original cancer lesion(s) resolve completely, this is called complete pathologic response (pCR). pCR and even a partial response, while good for the patient, can result in disappearance or poor visualization of the target and often render pre-operative image-guided localization by the radiologist more difficult and less reliable. This can result in unintended larger, more disfiguring breast cancer surgery. Therefore, if the SCOUT device can be placed prior to treatment response, when the lesion is clearly visualized on imaging, accurate image-guided targeting is optimal and thus placement and subsequent surgery should be more accurate. If this pilot study demonstrates successful performance of the device without device-related complications, it will bring improved value to future patients who will require fewer and/or less extensive pre-operative and surgical procedures. Some value may also be provided to subjects as the targeting before tumor shrinkage is expected to be more accurate.

Thus, this pilot study will assess the performance of FDA-cleared SCOUT system over a longer duration prior to breast and/or axillary lymph node surgery.

Inclusion Criteria:

• Patient is willing and able to provide informed consent. Patient SCOUT device(s) is placed as part of routine care or study but before neoadjuvant treatment begins.
• Patient is female.
• Patient is between the ages of 18 and 90 years.
• Patient has breast cancer and will undergo neoadjuvant therapy and excision at Memorial Healthcare System.
• Patient is willing and able to comply with all study procedures and be available to follow-up for the duration of the study (1 - 13 months).
• Patient reads or understands English or Spanish.

Exclusion Criteria:

• Patient is pregnant.
• Patient has pacemaker or implantable defibrillators (These have not been bench tested as of September 2016).
• Patient has known or suspected nickel allergy.
• Patient is scheduled or receiving investigational drugs for neoadjuvant regimen. (This could confound UADE of this device.)
• Patient has any condition that would place the individual at increased risk or preclude the individual's full compliance with or completion of the study.
• Patient has other malignancy except for adequately treated and cured basal or squamous cancer, curatively treated in situ disease or any other cancer for which the patient has been disease free for greater than or equal to 5 years.

0 months - 14 months. Reportable adverse events were collected from the time after informed consent is obtained until 30 days (for non-serious AEs) or 7 days (for SAEs) after the last day of study participation

Adverse events from underlying diseases and related to neoadjuvant treatments were not intended to be collected. The written Protocol was amended to clarify this point. All reported SAEs were unrelated to the investigational device and collected prior to the Protocol amendment. The collected events were all previously known as anticipated side effects of chemotherapy and fertility preservation.

Principal Investigator has left the organization.