Extranodal Rosai-Dorfman disease. Clinical and pathological characteristics in a patient with a pseudotumor of bone.

We report the clinical and pathological findings of a 19-year-old Venezuelan patient with a proximal tibial lesion showing the histological and immunohistochemical characteristics of Rosai-Dorfman disease. The radiological studies showed a lithic bone lesion that was interpreted as a giant cell tumor.