A Rare WHO Grade I Lesion of the Posterior Fossa with Recurrence Biological Behavior ­ Dysplastic Gangliocytoma of the Cerebellum: Case Report

Dysplastic gangliocytoma of the cerebellum (DGC) or Lhermitte-Duclos Disease is a rare lesion (World Health Organization [WHO] grade I) characterized by thickened folia and replacement of the internal granular layer by abnormal ganglion cells. More commonly, the compromised patients are young adults presenting ataxia, seizures, obstructive hydrocephalus, and increased intracranial pressure. Dysplastic gangliocytoma of the cerebellum is intimately associated with Cowden syndrome, a hereditary disorder caused by a germline mutation in the PTEN tumor suppressor gene on chromosome 10q23. Large neurons of DCG show vesicular nuclei with prominent nucleoli. Expansion of the internal granular layer determines vacuolization of the molecular layer and white matter, which can be related to the bright stripes identified on T2-weighted magnetic resonance imaging. Herein, the authors report a female patient who developed long- time recurrence of DGC and discuss pathological findings and differential diagnosis of this rare cerebellar lesion.

Lhermitte-Duclos Disease and Cowden Syndrome: A Case Report and Literature Review

Lhermitte-Duclos disease (LDD), also known as dysplastic gangliocytoma of the cerebellum, is a rare, usually benign, slow-growing tumor, that commonly affects patients aged 30 to 50 years-old. The manifestations of dysplastic cerebellar gangliocytoma are nonspecific and are related both to the mass effect produced by its growth and to the location of the lesion. Cerebellar symptoms such as ataxia are often present. In 40% of cases, the tumor is associated with Cowden syndrome, which is part of a group ofgenetic disorders called polypoid hamartoma complex. In this case report, the patient presented expansive lesion in the posterior fossa, compatible with LDD, associated with macrocephaly. These findings are consideredmajor criteria for Cowden syndrome. When together, they confirm the diagnoses. To our knowledge, this is the first report of the association of LDD and Cowden syndrome in Brazil.