Also known as: sinus histiocytosis with massive lymphadenopathy, cutaneous sinus histiocytosis

Clinical Features:

• Disease of unknown etiology which causes massive cervical lymphadenopathy with systemic symptoms
• The skin is the most common extranodal site to be involved.
• Skin-limited disease has been described.
• Cutaneous lesions present as single or multiple erythematous papules, nodules or plaques.

Histologic Features:

• Diffuse or nodular dermal proliferation of histiocytes with large nucleoli, vesicular chromatin and prominent nucleoli.
• Emperipolesis is frequently seen (histiocytes phagocytose other leukocytes).
• Admixed with the histiocytic infiltrate are variable numbers of lymphocytes, plasma cells, neutrophils and sometimes small numbers of eosinophils.
• In the center of the nodules of histiocytes there are dilated lymphatics filled with histiocytes.
• Surrounding the nodules of histiocytes are lymphoid aggregates with germinal centers and thick-walled blood vessels surrounded by plasma cells.
• The histiocytes are positive for S-100 and negative for CD1a, in contrast to Langerhan's cell histiocytosis.

Cases associated with this book:

Rosai-Dorfman disease
Author: Artur Zembowicz M.D. Ph.D.

Conference: Dermpedia Teaching Collection