Isolated cerebellar Rosai-Dorfman granuloma mimicking Lhermitte-Duclos disease

Rosai-Dorfman disease (RDD) is an idiopathic histioproliferative disorder that rarely involves the CNS. Rosai-Dorfman disease is exceedingly rare in the pediatric population and has never been observed in the cerebellum of a child. The authors present the case of a 14-year-old male with a cerebellar lesion having radiographic characteristics of Lhermitte-Duclos disease. After a period of observation with a presumptive diagnosis of Lhermitte-Duclos disease, the child underwent suboccipital craniotomy and resection of the lesion due to continuous suboccipital headaches. Histological examination of the tissue demonstrated RDD. The published literature on RDD is reviewed with an emphasis on differential diagnosis. (DOI: 10.3171/2009.3.PEDS0917)