Tumor-like Lesions in Patients with Granulomatosis with Polyangiitis: A Case Series.

Background Granulomatosis with polyangiitis (GPA) is a rare small vessel vasculitis. It usually involves the respiratory tract and kidney. Rarely, tumor-resembling inflammatory changes ensue. Objectives To report three unique cases of GPA presenting with tumor-like lesions in various organs. Methods We presented three cases of GPA. Case 1 presented with typical upper respiratory symptoms of GPA and a mediastinal mass. Case 2 presented with low back pain, a large retroperitoneal mass, and nodular skin lesions. Case 3 presented with epigastric pain and a paravertebral inflammatory mass. Results The patients were treated successfully with rituximab. Conclusions Clinicians should be aware of this presentation of granulomatosis with polyangiitis, which is known as Tumefaction Wegener's granulomatosis.