99mTc-HFAPI SPECT/CT in Pulmonary Fibrosis

This prospective study will investigate the potential usefulness of 99mTc labeled FAPI SPECT/CT in the diagnosis, treatment response assessment, and follow-up of pulmonary fibrosis.

Idiopathic pulmonary fibrosis refers to a specific form of chronic fibrous interstitial pneumonia that occurs spontaneously, limited to the lung, and shows features of usual interstitial pneumonia on high resolution computed tomography and histological examination. Radionuclide labeled FAPI has been developed as a new tracer for tumor and inflammatory lesions imaging. Recent studies have shown that FAPI PET/CT imaging is a promising new imaging method for pulmonary fibrosis. HFAPI is obtained by conjugating 99mTc-chelator moiety (6-hydrazinonicotinamide, HYNIC) with FAP targeting moiety. The aim of this study is to investigate the location and extent of 99mTc labeled FAPI tracer (99mTc-HFAPI) in normal and fibrotic lung tissue of patients with pulmonary fibrosis, and to explore the clinical significance of 99mTc-HFAPI SPECT/CT in the diagnosis, treatment response evaluation and follow-up of pulmonary fibrosis.

Patients of Pulmonary Fibrosis SPECT/CT imaging: The patients were subcutaneously injected with 99mTc-HFAPI and underwent SPECT/CT imaging.

Each patient receive a intravenous injection of 99mTc-HFAPI, and undergo SPECT/CT scan within specified time.

Qualitative and semi-quantitative analysis (T/N ratio of lesions and adjacent normal tissue, and early and late imaging) of 99mTc-HFAPI SPECT/CT for pulmonary fibrosis

Inclusion Criteria: suspected or confirmed pulmonary fibrosis patients; signed written consent. Exclusion Criteria: pregnancy; breastfeeding; known allergy against FAPI any medical conditions that are considered by the investigator to be likely to seriously interfere with study compliance