Extranodal Rosai-Dorfman Disease : Lung
Image Description
Extranodal Rosai-Dorfman disease (RDD) involving lung. The upper half shows relatively spared lung parenchyma. The alveolar septa are slightly thickened with fibrosis and chronic inflammation. The lower half shows more pronounced changes with dense fibrosis, histiocytic proliferation and lymphoid follicles.