Rosaï-Dorfman disease

Rosai-Dorfman disease (RDD), also known as sinus histiocytosis with massive lymphadenopathy (SHML), is a rare non-Langerhans cell histiocytic disorder characterized by the overproduction and accumulation of a specific type of white blood cell called histiocytes, primarily within the lymph nodes. The disease was first described by Juan Rosai and Ronald Dorfman in 1969. The hallmark clinical presentation is painless, bilateral, massive cervical lymphadenopathy (enlarged lymph nodes in the neck), often accompanied by fever, elevated erythrocyte sedimentation rate, weight loss, and hypergammaglobulinemia. A characteristic pathological finding is emperipolesis, where lymphocytes are found intact within the cytoplasm of histiocytes. While lymph node involvement is the most common manifestation, approximately 40-43% of patients develop extranodal disease, which can affect the skin, soft tissue, upper respiratory tract, bone, central nervous system, orbit, salivary glands, and other organs. Cutaneous involvement is the most frequent extranodal site and may present as papules, nodules, or plaques. Central nervous system involvement, though less common, can mimic meningiomas and may cause significant neurological complications. The cause of Rosai-Dorfman disease remains largely unknown, though associations with immune dysregulation, viral infections (including HHV-6 and EBV), and somatic mutations in the MAPK/ERK signaling pathway (including KRAS and MAP2K1 mutations) have been identified in some cases. The disease course is highly variable — many patients experience spontaneous remission without treatment, while others develop chronic or progressive disease requiring intervention. Treatment options include watchful waiting for asymptomatic cases, surgical excision for localized disease, corticosteroids, chemotherapy (such as cladribine or clofarabine), radiation therapy, and targeted therapies including MEK inhibitors for cases harboring activating MAPK pathway mutations. The prognosis is generally favorable, though outcomes depend on the extent and location of disease involvement.

Common questions about Rosaï-Dorfman disease