<aside>
Lhermitte–Duclos Disease (LDD), also known as dysplastic cerebellar gangliocytoma, is a rare, benign cerebellar lesion characterized by hamartomatous overgrowth of cerebellar ganglion cells.
</aside>
| Feature | Description |
|---|---|
| Genetic link | Strongly associated with PTEN mutations in Cowden syndrome |
| Pathogenesis | Dysplasia of the granular layer of cerebellum and overgrowth of ganglion cells |
| Nature | Hamartomatous rather than neoplastic |
Schematic diagram of the pathology of Lhermitte-Duclos disease. Currently, the disease is easily pathologically diagnosed as ganglion cell glioma or neuron-glioma. Imaging analysis usually reveals that the normal granular layer cells in the cerebellar lobe are replaced by dysplastic cortical neurones (ganglion cells), resulting in enlargement of the cerebellar lobe. The molecular layer of the brain lobe thickens and produces excessive myelination changes, which lead to layered changes on imaging. Therefore, for disease confirmation, a typical tiger striped sign on magnetic resonance imaging (MRI) is required. Therefore, imaging is of great significance for confirming a disease diagnosis.
Zhang H, Zhang Y, Liu X, et al. MR imaging features of Lhermitte–Duclos disease. Medicine. 2022;101(4):e28667-e28667. doi:https://doi.org/10.1097/md.0000000000028667
The repeating bilaminar cortical pattern evident on CT and MRI studies is compared with the histologic alterations that characterize Lhermitte-Duclos disease. The inner portion of the folia consisting of the white matter, the abnormal granular cell layer, and deep molecular layer, was hypodense on CT and hypointense on TI and hyperintense on T2 MR images. The outer portion of the folia consisting of the outer molecular layer and leptomeninges within effaced sulci was isodenselisointense on CT and MR studies. Vascular proliferation in the pia and adjacent outer cortex may be associated with calcifications or rarely contrast enhancement within the isodenselisointense bands.
K. Kulkantrakorn, Awwad EE, Levy B, et al. MRI in Lhermitte-Duclos disease. Neurology. 1997;48(3):725-731. doi:https://doi.org/10.1212/wnl.48.3.725
Epidemiology
| Feature | Detail |
|---|---|
| Incidence | Very rare |
| Age of onset | Typically young adults (20–40 years) |
| Sex predilection | No significant bias |
| Syndromic association | Up to 40% with Cowden syndrome |
Presentation:
| Symptom/Sign | Explanation |
|---|---|
| Headache | Due to mass effect or raised ICP |
| Ataxia | From cerebellar dysfunction |
| Nystagmus | Common due to vermian involvement |
| Papilledema | From hydrocephalus |
| Cognitive/psychiatric symptoms | Occasionally reported |
Association with Cowden Syndrome:
LDD is considered pathognomonic for Cowden syndrome and is included in the pathognomonic criteria per NCCN/ICC guidelines.
Diagnostic criteria: