Extranodal Rosai-Dorfman Disease in the Left Bulbar Conjunctiva: A Rare Case Report

Abstract

Rosai-Dorfman disease (RDD) is a non-Langerhans histiocytosis characterized by accumulation of S100-positive foamy histiocytes, frequently demonstrating emperipolesis within lymph nodes or extranodal tissues. Extranodal disease is reported in 43% of cases. We present a case of a healthy 11-year-old male with a non-mobile, rapidly enlarging 1.5 cm mass in the medial canthal area of his left superonasal bulbar conjunctiva, and a 3.5 cm firm rubbery left neck mass.  The patient denied any eye, neck, or weight loss symptoms. CMV, EBV, and bartonella antibody tested negative. Imaging report was noncontributory. Flow cytometry showed no evidence of lymphoproliferative neoplasm. The left conjunctival excision revealed histiocytic disorder of non-Langerhans cell type with xanthomatous changes. Immunostains showed positive CD20, PAX5, CD3, S100, CD68, CD163, FXIIIA, lysozyme, and fascin. Immunostains for CD1a, BRAF V600E, and ALK-1 were negative. It was clinically indeterminate whether the two masses involved an intraorbital malignant process with metastatic disease to the cervical lymph nodes, Hodgkin lymphoma, or an infectious etiology. In addition, S100 positivity is nonreactive in most cases of juvenile xanthogranuloma and does not rule out the diagnosis. Lymph node resection confirmed sinus histiocytosis with massive lymphadenopathy favoring RDD, histologically consistent with the conjunctival mass.

[N A J Med Sci. 2025;18(1):049-051.   DOI:  10.7156/najms.2025.1801049]

Key Words: Rosai-Dorfman Disease, non-Langerhans cell histiocytosis, sinus histiocytosis

with massive lymphadenopathy, lymph node, ophthalmic, conjunctiva, pediatrics