Rosai and Dorfman first characterised sinus histiocytosis with massive lymphadenopathy in 1969.¹ This condition most commonly presents as a massive painless cervical adenopathy in children or young adults of African ancestry. The lymphadenopathy typically has a protracted course, lasting for several years before spontaneously resolving. Complications can include compression of vital organs or associated anaemia or leucopenia. The results of chemotherapy or radiation treatments have generally been disappointing; however, surgical debulking, when necessary, has been effective.

Microscopic examination of the lymph nodes reveals a polymorphous infiltrate composed of plasma cells, other lymphocytes, and histiocytes. The histiocytes often contain phagocytised lymphocytes, a histological finding termed emperipolesis. Since these histiocytes fill and expand lymph node sinuses, the disease was first named morphologically as sinus histiocytosis with massive lymphadenopathy. Extranodal involvement, most commonly in the upper respiratory tract and stomach, displays a histology similar to lymph node infiltrates. Because extranodal infiltrates are often found in the absence of lymphadenopathy, the eponym Rosai-Dorfman disease is now preferred.²

The orbit is a common extranodal site of RDD.³ Four cases of RDD manifesting as an epibulbar conjunctival mass have also been reported.^4–7 In two of these cases, both in children, the epibulbar mass was an isolated finding.^5,7 We present RDD occurring as an isolated epibulbar mass in two adult patients.

CASE REPORTS

A 71 year old African-American man with a history of hypertension, benign prostatic hyperplasia, asthma, gout, and degenerative …