Cytomorphology and Histology Correlation of Rosai-Dorfman Disease: A 15-Year Study from a Tertiary Referral Centre in South India.

OBJECTIVES: Rosai-Dorfman disease (RDD) is an uncommon, benign histiocytic disorder of unknown etiology, typically presenting in young adulthood. We highlight the cytomorphology of RDD and correlate it with the histopathology.

STUDY DESIGN: All cases diagnosed as RDD on fine-needle aspiration cytology between January 2001 and June 2015 were included. Clinical details were obtained from medical records. The cytology smears were reviewed along with the histopathology and immunohistochemistry, wherever available.

RESULTS: The study included 10 cases ranging in age from 11 to 68 years (median 29). There was a male predominance with a male:female ratio of 1.5:1. The patients commonly presented with bilateral cervical lymphadenopathy. Extranodal involvement was seen in 2 cases in the nose and mandible, respectively. Of these 10 cases, 8 were later biopsied. The cytological features included numerous crescentic histiocytes, emperipolesis, reactive lymphocytes and plasma cells. A histological diagnosis of RDD was made in 7 out of 8 cases, and 1 was diagnosed as Hodgkin lymphoma.

CONCLUSION: FNA represents an efficient, minimally invasive, cost-effective and reliable technique for the diagnosis of RDD and may obviate the need for further biopsy. However, the disease has close differential diagnoses, including Langerhans cell histiocytosis, granulomatous lesions, and Hodgkin lymphoma. Hence, it must be remembered that there can be pitfalls when the diagnosis is made by cytology alone.