Among the more puzzling non-neoplastic necrotizing lesions of the head and neck area is Wegener's granulomatosis. This is a condition of unknown cause that may present (in the head and neck area) with ulceration of the nasal septum, sinus mucosa, oral mucosa, or external ear canal, or even destruction of the vocal cord. Diagnosis depends on the pathologic finding of a characteristic inflammatory reaction pattern (which, in its best-developed form, includes necrosis, granulomatous inflammation, and vasculitis) and the serum finding of an elevated antinuclear cytoplasmic antigen. Treatment is principally medical, with the use of powerful immunosuppressive agents. Distinction from other conditions that may mimic Wegener's granulomatosis (such as malignant lymphoma and infections) is of critical importance in constructing an appropriate treatment strategy.