Rapid onset of pulmonary infiltration due to histiocytic lymphoma

Five cases demonstrating the rapid onset of pulmonary infiltrates due to hystiocytic lymphoma are presented. In four cases the pulmonary infiltrate occurred at the time of initial presentation and the fifth case occurred 2 1/2 months after the original diagnosis. The radiographic manifestations are nonspecific. Lung biopsy, open or closed, is needed to confirm the diagnosis before initating appropriate therapy.