Aim: To present an interesting case of inflammatory pseudotumour in the right lung simulating a malignant epithelial tumour with locoregional dissemination on 18F-FDG PET/CT in a 63-year-old woman. Method: The patient was treated for asthma bronchiale for a long time.
The chest X-ray and CT scan showed a new soft tissue expansion in the right lung hilum, which was highly suspicious for a tumour. An 18F-FDG PET/CT imaging was performed to complete staging before surgical intervention.
A whole-body PET/CT scan was performed from the base of the skull to the mid-thighs 60 minutes after intravenous administration of 18F-FDG with an activity of 416 MBq (5.1 MBq/kg). The acquisition time of PET imaging was 2.5 minutes per bed projection and a total of 7 bed projections were performed.
Native CT imaging was performed in an identical range. Results: PET/CT showed intense 18F-FDG uptake in tumorous expansion in the right lung hilum and in mediastinal lymph nodes.
The finding was evaluated as a viable tumour expansion in the right lung hilum with viable tumor lymphadenopathy in the mediastinum. This was followed by a right-sided mid-lung lobectomy and mediastinal lymphadenectomy.
However, histological examination excluded malignant epithelial tumor structures in the resected lung lobe and lymph nodes; an inflammatory pseudotumour was proven. Conclusion: 18F-FDG PET/CT imaging showed an inflammatory pseudotumour in the right lung simulating a malignant epithelial tumour with dissemination to the mediastinal lymph nodes.