Abstract OT2-01-02: A pilot study to evaluate preoperative localization of breast and axillary lesions in neoadjuvant patients 31-365 days prior to surgery
Authors: Hayes MK , Bloomquist EV , Wright HR 
Published: February 2018

SCOUT standard of care preoperative localization has been used in over 300 breast cancer patients at our hospital and over 12,000 breast cancer patients in 100 US sites between June 2015-May 2017. The radiologist performs SCOUT localization with Mammography, Ultrasound or CT guidance 0- 30 days prior to surgery.

In this study, we will evaluate the performance of SCOUT over longer duration (31 - 365 days) to address the needs of patients who require neoadjuvant treatment prior to definitive surgery. Placement of SCOUT localization prior to treatment response, when the lesion is clearly visualized on imaging, should be more accurate. Successful neoadjuvant treatment, which results in a complete or partial response often renders preoperative image-guided localization by the radiologist a more difficult and less reliable procedure and can result in unintended larger, more disfiguring breast cancer surgery.

This pilot study will assess whether placement of the SCOUT prior to neoadjuvant treatment allows for longer-term preoperative localization of breast/axillary lesions. Successful performance with no significant adverse events may prove valuable to future patients who will require fewer and/or less extensive preoperative and surgical procedures. Some value may also be provided to subjects as the targeting before tumor shrinkage is expected to be more accurate.

Trial design Radiologists perform SCOUT localization using Mammography, Ultrasound or CT guidance 31 - 365 days preoperatively. Surgeons use the SCOUT system to locate and excise the SCOUT and target tissue.

Eligibility criteria The study population consists of 25 - 35 adult surgical patient volunteers who plan to have definitive breast cancer surgery at our hospital after neoadjuvant treatment.

Subject Inclusion Criteria

· Female patient 18 - 90 years old

· Patient is willing and able to comply with all study procedures and follow-up (1 - 13 months)

· SCOUT localization is performed before neoadjuvant treatment begins.

Subject Exclusion Criteria

· Patient is pregnant, has a pacemaker or implantable defibrillators

· Patient has known or suspected nickel allergy

· Patient is receiving an investigational drug that could potentially confound assessment of adverse device events

Statistical methods

This pilot study will provide an estimate for the efficacy of the method.

Simple statistics will be used to evaluate primary and secondary endpoint data.

Primary Endpoint

The primary endpoint of this study is successful surgery, defined as a SCOUT localization at the target lesion, which remains in place 31 - 365 days preoperatively, and can successfully be removed with target tissue during surgery.

Secondary Endpoints

· Number of days prior to surgery (31 - 365) that the SCOUT is placed by the radiologist to localize the target breast / axillary tissue.

· Success rate of preoperative SCOUT placement by radiologist and SCOUT stability (within 1 cm of the center of the target tissue) for 31- 365 days.

ClinicalTrials.gov identifier: NCT03015649

Contact information Mary Hayes, MD

Present accrual/target accrual: 4/30.

Citation Format: Hayes MK, Bloomquist EV, Wright HR. A pilot study to evaluate preoperative localization of breast and axillary lesions in neoadjuvant patients 31-365 days prior to surgery [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-01-02.