Extranodal Rosai-Dorfman disease arising in the right atrium: a case report with literature review.

Rosai-Dorfman disease is a rare, benign histiocytic proliferative disorder that commonly affects the lymph nodes. Although extranodal involvement has been reported in diverse sites, manifestation in the cardiovascular system is extremely uncommon. Specifically, the involvement of the heart by Rosai-Dorfman disease is an extraordinarily infrequent event.