Pulmonary lymphoma of large B-cell type mimicking Wegener's granulomatosis.

A 27-year-old man with a primary pulmonary lymphoma of large B-cell type is described. Symptoms involved both the upper and lower respiratory tract. A chest roentgenogram showed a dense mass with cavitation. Transbronchial biopsy specimens revealed no atypical cells, rather they demonstrated granulomatous infiltration and vasculitis consistent with but not conclusively diagnostic of Wegener's granulomatosis. The pulmonary mass became smaller after sulfamethoxazole-trimethoprim therapy. These features suggested Wegener's granulomatosis. However, an open biopsy specimen was diagnostic for diffuse lymphoma of large B-cell type. High-grade pulmonary lymphoma should be considered in the differential diagnosis of patients with clinical and pathologic features suggesting Wegener's granulomatosis.