A challenging case of drug-related acute fibrinous and organizing pneumonia: A rare case report.

A 65-year-old man presented with intermittent fever and progressive shortness of breath. He responded poorly to antibiotics and corticosteroids (methylprednisolone 40 mg/d). Chest computed tomography scans showed diffuse consolidations and ground glass density patchy opacities in both lungs and these lesions progressed rapidly. The diagnosis of acute fibrinous and organizing pneumonia (AFOP) was confirmed through transbronchial cryobiopsy. This patient had prostate cancer with bone metastasis for 4 months and took the anti-prostate cancer medications including apalutamide and leuprorelin acetate. Considering his medication history, the patient was diagnosed with AFOP induced by anti-prostate cancer medications through panel discussion of multidisciplinary teams. Intravenous methylprednisolone of 500 mg/day was administered for 3 days and then slowly tapered. The patient's shortness of breath gradually subsided. In addition, the lesions in the lungs improved significantly on follow up imaging. AFOP induced by anti-prostate cancer medications is rare. To our knowledge, this is the first reported case and high-dose glucocorticoid treatment may be required in some of these cases.