Pulmonary lymphoproliferative disorders.

Nonlymphomatous pulmonary lymphoproliferative disorders include plasma cell granuloma, Castleman's disease, pseudolymphoma, lymphocytic interstitial pneumonitis, angioimmunoblastic lymphadenopathy, and lymphomatoid granulomatosis. They are thought to represent a hyperplasia of the pulmonary immune system in response to chronic antigenic stimulation. A description of the variable clinical, radiographic, and pathologic features of each entity is presented.