RESUMO
Wegener's granulomatosis is a disease with an unknown etiology that is characterized by necrotizing granulomatous vasculitis involving the upper and lower respiratory tract and the kidneys. The typical pulmonary findings are bilaterally involved multiple variable sized nodules. We report a case of Wegener's granulomatosis that presented as a single lung mass. A male patient presented with a nasal obstruction, arthralgia, cough, and intermittent dyspnea. The chest radiograph showed a mass, approximately 4.5 cm in diameter, in the right lower lobe. Lung cancer or tuberculosis was initially considered. However, the clinical, laboratory and pathological findings of the mass indicated Wegener's granulomatosis. The patient was administered prednisolone and cyclophosphamide, and improved temporarily. Unfortunately, the immunocompromised patient expired as a result of respiratory failure with pneumonia.