Exploring the Diagnostic Utility of 68 Ga-FAPI-46 PET/CT in Diverse Pulmonary Pathologies : A Comparative Analysis...

Area of Science:

• Nuclear Medicine
• Oncology
• Radiochemistry

Background:

• Lung cancer is a leading global cause of cancer mortality.
• Distinguishing benign from malignant lung lesions is challenging with conventional imaging like CT and 18F-FDG PET.
• Novel PET tracers are being investigated for improved diagnostic accuracy.

Purpose of the Study:

• To prospectively compare the efficacy of 68Ga-FAPI-46 PET and 18F-FDG PET in characterizing lung lesions.
• To evaluate the diagnostic performance of both tracers in differentiating benign from malignant lung nodules.

Main Methods:

• Patients with suspected lung lesions underwent both 68Ga-FAPI-46 PET/CT and 18F-FDG PET/CT scans.
• Histopathology was used to classify lesions as benign or malignant.
• Semi-quantitative analysis (SUVmax) and ROC analysis were performed to determine optimal cut-offs for differentiation.

Main Results:

• Sixty-six patients with 14 benign and 52 malignant lesions were analyzed.
• Median SUVmax values for benign and malignant lesions were significantly different for both 68Ga-FAPI (9.8 vs. 14.7, P=0.002) and 18F-FDG (8.8 vs. 13.5, P=0.001).
• ROC analysis yielded SUVmax cut-offs of 12.2 (AUC=0.77) for 68Ga-FAPI and 9.5 (AUC=0.78) for 18F-FDG.

Conclusions:

• 68Ga-FAPI-46 PET/CT demonstrates potential as an alternative imaging modality for lung lesion characterization.
• The tracer requires cautious interpretation due to potential false positives in benign lesions and false negatives in low-grade tumors.
• Histopathologic confirmation remains essential for definitive diagnosis.