Background: The aim of this pilot trial was to study the feasibility of sentinel node percutaneous preoperative gamma probe-guided biopsy as a valid preoperative method of assessment of nodal status compared to surgical sentinel lymph node biopsy.
Material/Methods: This prospective study enrolled 10 consecutive patients without evidence of axillary lymph node metastases at preoperative imaging. All patients underwent sentinel node occult lesion localization (SNOLL) using radiotracer intradermic injection that detected a “hot spot” corresponding to the sentinel node in all cases. Gamma probe over the skin detection with subsequent ultrasonographically guided needle biopsy of the sentinel node were performed. The percutaneous needle core histopathological diagnosis was compared to the results of the surgical biopsy.
Results: Preoperative sentinel node identification was successful in all patients.
Conclusions: The combination of preoperative gamma probe sentinel node detection and ultrasound-guided biopsy could represent a valid alternative to intraoperative sentinel node biopsy in clinically and ultrasonographically negative axillary nodes, resulting in shorter duration of surgery and lower intraoperative risks.

Keywords: Radioactive Tracers, Prospective Studies, Pilot Projects, Neoplasm Staging - methods, Image-Guided Biopsy - methods, Breast Neoplasms - pathology, Biopsy, Needle - methods, Sentinel Lymph Node Biopsy - methods, Ultrasonography - methods