Systemic and craniospinal rosai dorfman disease with intraparenchymal, intramedullary and leptomeningeal disease

Abstract

Rosai Dorfman disease is a rare histiocytic disorder of over-production of non-Langerhans histiocytes, which typically manifests with massive lymphadenopathy and sinonasal involvement. We report a rare case of systemic and disseminated craniospinal Rosai-Dorfman disease with intraparenchymal and leptomeningeal involvement, but no sinus or dural-based disease. The diagnosis was established by biopsy of a hypothalamic mass. Additionally, UCSF500 Next Generation Sequencing demonstrated a solitary pathogenic alteration affecting the BRAF oncogene, which supports the morphologic and immunohistochemical diagnosis of RosaiDorfman disease.