Steroid responsive inflammatory myofibroblastic tumor of the lung evaluated by FDG PET/CT imaging

A 68-year-old gentleman was referred for 18F-FDG PET/CT for a pulmonary mass in the left upper lobe which demonstrated intensely FDG-avid confluent pulmonary consolidation in the left upper lobe (SUVmax 15.1). Histopathologic biopsy of the left upper lobe lung mass was consistent with inflammatory myofibroblastic tumor (IMT). The patient was started on steroid treatment in conjunction with antibiotics. Follow-up FDG PET/CT 3 weeks after commence of treatment showed remarkable response of the IMTs to therapy with much less avid FDG uptake (SUVmax 5.4) and marked improvement in the pulmonary consolidation. Nevertheless, the patient underwent left upper lobe lobectomy due to evidence of persistent cystic disease and malignant potential associated with IMTs. Final histopathology was consistent with IMT with no evidence of malignancy.