Role of the Fibroblast Activation Protein (FAP) as Biomarker of Fibrotic Lung Diseases

Role of the Fibroblast Activation Protein (FAP) as Biomarker of Fibrotic Lung Diseases

To evaluate the effect of an anti-fibrotic treatment initiation on the fibrotic activity as assessed by FAPI PET/CT.

To evaluate the use of the fibroblast activation protein (FAP) as a biomarker of fibrotic lung disease (idiopathic pulmonary fibrosis (IPF) and non-IPF ILDs). The study will include both analysis of FAP expression in samples stored in the biobank of the department of Pneumology (BAL, blood, induced sputum and EBC) (cohort A) and lung FAPI uptake on PET/CT scans performed at the department of Nuclear Medicine:

• before and after the initiation of an antifibrotic therapy (IPF or PPF) (cohort B)
• before and after the initiation of corticosteroid therapy in case of an acute exacerbation of ILD (cohort C)
• before and after the initiation of an immunosuppressive drug in the context of non-IPF pulmonary fibrosis (cohort D).
• before lung transplantation, surgery or biopsy to correlate with FAP expression determined by immunohistochemical analysis (IHC) (cohort E).

Inclusion Criteria:

• Adults patients with a fibrotic lung disease (idiopathic pulmonary fibrosis (IPF) or non-IPF fibrotic ILD) as defined according to the 2022 ATS/ERS/JRS/ALAT Clinical Practice Guidelines

Exclusion Criteria:

• Pregnant or nursing patients
• Patients with another significant medical condition which, in the investigator's opinion, may interfere with the completion of the study.
• Patients with an active lung neoplasm or any active neoplasm for blood samples