Handheld PET Probe for Pediatric Cancer Surgery

Area of Science:

• Nuclear Medicine
• Oncology
• Surgical Technology

Background:

• 18F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) scans are vital for monitoring pediatric cancers.
• Radio-guided surgery (RGS) using handheld PET probes is an emerging technique for localizing FDG-avid lesions.
• The clinical utility of PET probes for identifying occult FDG-avid tumors in pediatric patients requires further assessment.

Purpose of the Study:

• To evaluate the effectiveness of a handheld PET probe in localizing occult 18F-fluorodeoxyglucose (FDG)-avid tumors in pediatric cancer patients.
• To assess the performance of the PET probe in a clinical setting for radio-guided surgery (RGS).

Main Methods:

• PET probe functionality was initially assessed using a PET/CT calibration phantom with simulated tumors.
• The study involved eight pediatric patients with FDG-avid cancers undergoing tumor excision guided by IV FDG and PET probe.
• Gamma counts and ex vivo tumor-to-background ratios (TBR) were measured during surgery.

Main Results:

• The PET probe successfully detected FDG photon emissions from simulated tumors, though specificity decreased with background FDG.
• In clinical cases, PET probe gamma counts were significantly higher in tumors than adjacent benign tissues (median TBR 4.0).
• The PET probe confirmed the excision of occult FDG-avid tumors in all eight pediatric patients, with 12 of 17 lesions positive for malignancy.

Conclusions:

• Handheld PET probes are a valuable tool for localizing occult FDG-avid tumors in pediatric cancer patients.
• This technology facilitates accurate tumor excision during radio-guided surgery (RGS).
• PET probe-guided surgery shows promise for improving outcomes in pediatric oncology.