Rosai-Dorfman Disease : Immunophenotype
The histiocytes in Rosai-Dorfman disease are positive for S-100 and histiocytic markers, including CD4, CD11c, CD14, CD33, CD64, CD163, and CD68. Lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin may be expressed. CD1a is rarely positive (less than 10% of cases). CD30 shows non-specific cytoplasmic staining in about 50% of cases. CD3 and CD20 are negative. This image show S-100 positivity in histiocytes nicely highlighting emperipolesis (presence of intact lymphocytes and plasma cells within cytoplasm) from a case of Rosai-Dorfman disease. Image courtesy of: Dr. T. Slavik, ARP Press; used with permission.