Purpose: To report a case of localized orbital Castleman's disease of mixed cell type with a follow-up of 20 years.
Methods: A female patient presented at the age of 12 years with constitutional symptoms and left-sided proptosis. Laboratory tests revealed marked hypergammaglobulinaemia and high erythrocyte sedimentation rate (ESR), suggesting an immunological disturbance. A CT scan and MRI showed an infiltrating orbital mass lateral to and behind the eye.
Results: Histological examination of orbital biopsies showed a lymphoid lesion consistent with Castleman's disease of the mixed cell type. The patient was treated with systemic steroids, immunosuppressives and irradiation. She is now 33 years old and has been without relapse for the last 7 years.
Conclusion: Orbital involvement in Castleman's disease is very rare. The clinical course, good prognosis and histological picture of the present case favour the diagnosis of localized Castleman's disease of mixed cell type. The successful medical treatment suggests that such a regime may substitute for surgery when the latter proves difficult.