Mammary Extranodal Rosai-Dorfman Disease With and Without Associated Axillary Lymphadenopathy: Insights for Practitioners of Breast Pathology

Rosai-Dorfman disease is a rare proliferative histiocytic disorder of lymph nodes that is descriptively known as sinus histiocytosis with massive lymphadenopathy. Extranodal involvement of the parenchyma of the breast is uncommonly reported, with fewer than 50 cases of mammary extranodal disease detailed in the English-language literature. We characterize a retrospective series of adult female patients from a single institution with...