SNMMI ’21: 68Ga-FAPI-PET Non-invasively Detects, Assesses Pulmonary Fibrosis
Using a68Ga-labeled fibroblast activation protein inhibitor (FAPI) with PET imaging can noninvasively identify and monitor pulmonary fibrosis. Researchers at SNMMI 2021 presented a study demonstrating that by binding to activated fibroblasts present in affected lungs, FAPI-PET allows for direct imaging of the disease process.
A major challenge in diagnosis and treatment of idiopathic pulmonary fibrosis (IPF) is the lack of a specific diagnostic tool that can noninvasively diagnose and assess disease activity, which is crucial for the management of pulmonary fibrosis patients.
“CT scans can provide physicians with information on anatomic features and other effects of IPF but not its current state of activity. We sought to identify and image a direct noninvasive biomarker for early detection, disease monitoring and accurate assessment of treatment response,” said Carolina de Aguiar Ferreira, PhD, a research associate at the University of Wisconsin-Madison in Madison, Wisconsin.
In the study, researchers targeted the fibroblast activation protein (FAP) that is overexpressed in IPF as a potential biomarker. Two groups of mice—one group with induced pulmonary fibrosis and one control group—were scanned with the FAPI-based PET/CT radiotracer68Ga-FAPI-46 at multiple time points. Compared to the control group, the mice with induced pulmonary fibrosis had a much higher uptake of the radiotracer, allowing researchers to successfully identify and evaluate areas of IPF.
“Further validation of68Ga-FAPI-46 for the detection and monitoring of pulmonary fibrosis would make this molecular imaging tool the first technique for early, direct, and noninvasive detection of disease. It would also provide an opportunity for molecular imaging to reduce the frequency of lung biopsies, which carry their own inherent risks,” noted Ferreira. “This development will demonstrate that functional imaging can play an invaluable role in evaluation of the disease process.”