Aspergillus fumigatus: Is Dual-Tracer 18 FDG/ 68 Ga-FAPI PET/CT Capable of Distinguishing Fungal Infection and Unspecific Inflammation From Recurrent Lung Cancer?

A 61-year-old woman, referred for recurrent pneumonia over a period of 3 months with insufficient response to antibiotic treatment, presented with coughing and intense right-sided chest pain. Previously, she underwent right upper lobectomy for locally advanced non-small cell lung cancer (squamous cell carcinoma) followed by adjuvant chemotherapy and subsequent partial chest wall resection with polytetrafluoroethylene net insert due to a pleurocutaneous fistula. 18 FDG plus a 68 Ga-labeled fibroblast activation protein inhibitor ( 68 Ga-FAPI) PET/CT scans were performed to rule out non-small cell lung cancer recurrence. Pathological workup with bronchoscopy and endobronchial ultrasound-guided transbronchial fine-needle aspiration of the lymph nodes showed no evidence of malignancy, but microbiology confirmed Aspergillus fumigatus infection of the middle lobe. Thus, the patient transitioned from antibiotic to antifungal therapy; no second-line oncologic treatment was initiated.