Rosai-Dorfman disease with spinal cord compression: a diagnostic challenge.

Purpose: Rosai-Dorfman disease (RDD) is an uncommon benign histiocytic proliferative disorder commonly involving the cervical lymph nodes and less frequently extranodal sites, including, rarely, the central nervous system, mainly intracranially. Spinal involvement is unusual. RDD is characterized by pathognomonic histopathological features, which are decisive in the definitive diagnosis.