SCOUT® Radar Localization at Time of Breast Biopsy

Evaluate surgical utilization of SCOUT reflectors placed at breast biopsy.

Consent was waived for this retrospective IRB-approved, HIPAA-compliant study. Breast biopsy examinations that reported the term "SCOUT" between January 2021 and June 2022 were identified using an institutional search engine. Cases were included if a SCOUT reflector was placed at time of breast biopsy and excluded if lesion pathology was already known. Analysis was performed at the lesion level. A multivariate-regression analysis evaluated 6 variables with potential impact on SCOUT utilization.

One hundred twenty-one lesions in 112 patients met inclusion criteria. Biopsy yielded 93% (113/121) malignant, 3% (4/121) elevated risk, 2% (2/121) benign-discordant, and 2% (2/121) benign-concordant results. Two cases lost to follow-up were excluded. SCOUT reflectors were utilized for lumpectomy (58%, 69/119 lesions) and excisional biopsy (6%, 7/119 lesions). SCOUTs were not utilized due to mastectomy (23%, 27/119), subsequent wire localization (2%, 2/119), and nonsurgical cases (12%, 14/119). Reflector placement utilization was 52% higher for findings less than 3.5 cm in size (P <.001), 33% higher in patients without prior treated breast cancer (P = .012), and 19% higher in patients with no suspicious ipsilateral lymph node (P = .048).

SCOUT reflector placement at time of biopsy was utilized for surgery 64% (76/119) of the time, although most (98%, 119/121) biopsies were malignant, elevated risk, or benign-discordant. Factors increasing reflector utilization include smaller lesion size, no suspicious ipsilateral lymph node, and no prior treated breast cancer.