Lymphoid Lesions of the Lung

Question 1

Histopathology of rheumatoid arthritis-associated lung disease

Answer 1

Formation of peribronchial lymphoid follicles with germinal centers (follicular bronchiolitis) is characteristic, but not specific.

This is accompanied by a lymphoplasmacytic infiltrate in the vicinity of these nodules.

Type II pneumocyte hyperplasia is usually present.

“Rheumatoid nodules” are nodules of acellular fibrinoid necrosis lined by pallisading epithelioid histiocytes. The density of fibrin and paucity of cells in these lesions is another hallmark of rheumatoid arthritis.

Question 2

Answer 2

Follicular bronchiolitis

Follicles associated with bronchioles.

This process is often seen in association with immunodeficiency states, collagen vascular diseases, or in patients with chronic obstructive pulmonary disease.

CXR w/ reticular or reticulonodular infiltrates.

Question 3

Answer 3

Nodular lymphoid hyperplasia

(aka nodular BALT hyperplasia)

Reactive process characterized by follicular lymphoid hyperplasia with interfollicular plasmacytosis and prominent reactive germinal centers. May be associated with collagen-vascular disorders or autoimmune diseases.

The germinal centers in the nodules display prominent polarity and are surrounded by a well-developed mantle zone. There is striking interfollicular lymphoplasmocytosis, but atypical cells or transformed lymphocytes are not a feature of the process. Sharply demarcated and do not extend along alveolar septa or into the alveolar walls.

CXR may show confluent nodules up to 5 cm.

Question 4

Answer 4

Diffuse lymphoid hyperplasia

Formerly designated as lymphoid interstitial pneumonia

Reactive process characterized by a polyclonal proliferation of small lymphocytes and plasma cells occupying the pulmonary interstitium and distending the alveolar walls. Small follicles with residual germinal centers showing a distribution reminiscent of FB may be seen admixed with the diffuse lymphoid infiltrates. No atypical or transformed lymphocytes are present. Focal infiltration of bronchial epithelium by small lymphocytes may lead to the formation of lymphoepithelial lesions.

Common manifestation in the lung of patients with a number of collagen vascular diseases, autoimmune disorders, and immunodeficiency conditions. Often accompanied by polyclonal gammopathy or hypergammaglobulinemia

In some instances, DLH may act as a precursor lesion that can progress to mucosa-associated lymphoid tissue (MALT) lymphoma.

Question 5

Common primary lymphomas of the lung

Answer 5

Marginal zone (MALT)
DLBCL
ALCL
Hodgkin