Extranodal Rosai-Dorfman disease:a clinicopathological analysis of 3 cases

Objective To study the clinicopathological features,diagnosis and differential diagnosis of extranodal Rosai-Dorfman disease(RDD). Methods Clinical data,sections of hematoxylin-eosin and immunohistochemical staining were analyzed in 3 cases of RDD. Results The patients were 2 males and 1 female,aged from 13 to 63 years.The lesions were located in the central nervous system,salivary glands and skin,rspectively.Histologically,the lesions were characterized by variable numbers of large histiocytes with emperipolesis,accompanied by infiltration of lymphocytes and plasma cells.The histiocytes were positive for S-100 protein,CD68 and Mac387. Conclusion Extranodal RDD is a very rare histiocytic proliferative disorder which has distinct morphologic feature.Systemic involvement is rare and its prognosis good.It should be differentiated from other types of histiocytosis such as langerhans cell histiocytosis,chronic inflammation and other lesions.