Abdominal and pelvic manifestations of Rosai-Dorfman disease: a review of four cases.

Rosai-Dorfman disease is a rare disorder of unknown etiology caused by the proliferation of histiocytes within lymph nodes, predominantly in the cervical chain. Extranodal sites may be involved as well, with involvement of nearly every organ system described in the literature. Abdominal and pelvic manifestations of Rosai-Dorfman disease are extremely rare. We present four cases of abdominal and pelvic involvement by Rosai-Dorfman disease, specifically within the biliary tract, pancreas, spleen, and presacral space. Of note, a presacral mass was present in three of the four patients, and although not previously reported in Rosai-Dorfman disease, may suggest the diagnosis in the proper clinical scenario.