Pulmonary Processes of Mature-Appearing Lymphocytes: Pseudolymphoma, Well-Differentiated Lymphocytic Lymphoma, and Lymphocytic Interstitial Pneumonitis

Abstract

Diagnoses in the patients were confirmed by recently developed immunochemical staining techniques. Radiographic findings in pseudolymphoma were different from those in well-differentiated lymphocytic lymphoma, and clinical findings in lymphocytic interstitial pneumonitis were different from those in the other 2 types of lesions. The interstitial infiltrate of lymphocytic interstitial pneumonitis had 2 patterns: basilar with an alveolar component and diffuse with associated honeycombing. Pseudolymphoma and lymphocytic interstitial pneumonitis are benign polyclonal inflammatory processes without malignant potential. Well-differentiated lymphocytic lymphoma, a monoclonal neoplasm, often has an indolent course.