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26 February 2014 - Case #302

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Thanks to Dr. Don Xu, University of California, San Diego, for contributing this case.


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Case #302

Clinical history:
A 45 year old woman presented with a right breast mass, which was biopsied.

Microscopic images:



What is your diagnosis?

Click here for diagnosis and discussion:


Diagnosis: Rosai-Dorfman disease

Discussion:
Rosai-Dorfman disease, also called sinus histiocytosis with massive lymphadenopathy, is a disorder of massive lymph node involvement that may also involve extranodal sites. It often presents with systemic symptoms (fever, leukocytosis, anemia), and most commonly involves the skin, subcutis / soft tissue, upper respiratory tract, bone, eye or CNS. Cases in the breast are rare.

Grossly, there are circumscribed, often multinodular masses in the breast stroma, which typically do not involve the dermis or subcutis. Histologically, large histiocytes are present with abundant pale eosinophilic cytoplasm and mildly atypical round vesicular nuclei (Am J Surg Pathol 1997;21:664). The background shows lymphocytophagocytosis (emperipolesis) in a background of mature lymphocytes and plasma cells. The histiocytes are immunoreactive for S100 and CD68 and negative for CD1a.

The differential diagnosis includes other histiocyte-like disorders:

Rosai-Dorfman disease usually resolves spontaneously, although systemic cases may cause death. Recent reports suggest that a subset of Rosai-Dorfman disease exhibit features of IgG4 related disease (Korean J Pathol 2012;46:489, Am J Clin Pathol 2013;139:622, Am J Clin Pathol 2013;140:395).


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