PET Probe-Guided Surgery in Patients with Breast Cancer: Proposal for a Methodological Approach.

Background: Although it is valuable for detecting distant metastases, identifying recurrence, and evaluating responses to chemotherapy, the role of F-18-fluorodeoxyglucose positron-emission tomography/computed tomography (F-18-FDG PET/CT) in assessing locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. In the current report, we describe a new PET probe-based clinical approach, with evaluation of the technical performance of a handheld high-energy gamma probe for intraoperative localization of breast carcinomas, and evaluation of lymph node metastases during radio-guided oncological surgery. Patients and Methods: Three patients underwent a PET/CT scan immediately prior to surgery following the standard clinical protocol. Intraoperatively, tumors were localized and resected with the assistance of a hand-held gamma probe. PET-guided assessment of the presence or absence of regional nodal spread of malignancy was compared with the reference standard of histopathological examination. Results: In all three cases, perioperative 18F-FDG PET/CT imaging and intraoperative gamma probe detection verified complete resection of the hypermetabolic lesions and demonstrated no additional suspicious occult disease. Conclusion: This innovative approach demonstrates great promise for providing real-time access to metabolic and morphological tumor information that may lead to an optimal disease-tailored approach. In carefully selected indications, a PET probe can be a useful adjunct in surgical practice, but further trials with a larger number of patients need to be performed to verify these findings.