Non-neoplastic pulmonary lymphoid lesions
- aDepartment of Pulmonary and Mediastinal Pathology, Armed Forces Institute of Pathology, 6825 N W 16th Street, Bld 54, Rm M003B, Washington, DC 20306-6000, USA, bDepartment of Thoracic Radiology, Armed Forces Institute of Pathology
- Dr W D Travis
Pulmonary lymphoid lesions encompass a spectrum of inflammatory and reactive lesions that are often difficult to diagnose since they are difficult to differentiate from other reactive and neoplastic entities (box 1). Understanding these lymphoid lesions is complicated by the evolution of concepts, criteria, and terminology over the past few decades. This review will attempt to summarise a historical perspective on this subject and present the current concepts of pulmonary lymphoid lesions.
Intrapulmonary lymph node
Follicular bronchiolitis (diffuse lymphoid or MALT hyperplasia)
Lymphocytic interstitial pneumonia
Nodular lymphoid hyperplasia
- B cell
Extranodal marginal zone B cell lymphoma of MALT type
Diffuse large cell lymphoma
- T cell
Peripheral T cell lymphoma
Anaplastic large cell lymphoma
- Special types of lymphoma
Primary effusion lymphoma
Lymphocytic leukaemia, acute and chronic
Non-lymphocytic leukaemia, acute and chronic
Box 1 Lymphoid lesions of the lung. MALT = mucosa associated lymphoid tissue.
This review will focus on the major pulmonary non-neoplastic lymphoid lesions which include intrapulmonary lymph nodes, follicular bronchitis/bronchiolitis, lymphocytic interstitial pneumonia, and nodular lymphoid hyperplasia.1-3 The terms “lymphocytic interstitial pneumonia” or “diffuse lymphoid hyperplasia” have sometimes been used for both lymphocytic interstitial pneumonia and follicular bronchiolitis. However, in this review lymphocytic interstitial pneumonia and follicular bronchiolitis are regarded separately.
Intrapulmonary lymph nodes
Intrapulmonary lymph nodes in the periphery of the lung are usually situated in a subpleural location or adjacent to interlobular septa.2 In one necropsy study they were found in the lungs of 18% of patients.4
CLINICAL AND RADIOLOGICAL FEATURES
They are usually discovered as an incidental radiographic finding in an asymptomatic patient.2 Most patients who undergo resection for intraparenchymal lymph nodes are middle aged or older and have a history of cigarette smoking and organic dust …