Intercostal Nodular Fasciitis Mimicking Recurrence of Malignant Lymphoma on FDG-PET/CT.

Nodular fasciitis (NF) is a benign, self-limited soft tissue lesion typically involves the extremities and the head and neck region. We report a rare case of NF arising in the intercostal space of a 74-year-old man. FDG-PET/CT after the achievement of complete remission after lymphoma treatment revealed intercostal mass and intense FDG uptake (SUVmax 7.3), raising concern for tumor recurrence. Surgical excision was performed and histopathologic examination confirmed NF. This case highlights the diagnostic challenge of NF and the importance of considering it in the differential diagnosis of FDG-avid nodules even in the uncommon site such as chest wall.