Lhermitte–Duclos disease

Lhermitte -Duclos disease (LDD, also dysplastic gangliocytoma ) is a rare neoplasm of the cerebellum due to a mutation in the PTEN gene and thus is part of the PTEN Hamartoma Tumor Syndrome. It is also described as a form of Cowden syndrome.

The first description of the disease in 1920 by Jacques Jean Lhermitte and P. Duclos.

Pathology and histopathology

According to the WHO classification of tumors of the central nervous system, it is one of the grade I tumors. The disease, however, shows the same characteristics of a benign neoplasm and a deformity, so that the exact classification is still unclear. Even if it could be a hamartoma is controversial among experts.

With the emergence of the tumor suppressor gene PTEN plays a role. The Cowdensyndom underlies a germline mutation of the PTEN gene. In mouse models, the role of the PTEN gene could be detected in the pathogenesis of Lhermitte -Duclos disease: A targeted elimination of PTEN in the cerebellum leads to folding and cell migration disorder similar to the architecture of human disorders.

At the cellular level, one sees dysplastic ( hypertrophic and later blistered swollen ( vacuolated ) ) Purkinje cells. The stratification of the cerebellum is reversed ( inverted) and the granule cell layer is largely resolved.

Symptoms, Diagnosis and Treatment

The clinical symptoms include headache, movement disorders and tremor (shaking ), blurred vision and an enlargement of the head that can mimic hydrocephalus. The complaints take months to years to slowly.

The electroencephalogram may be changed. Magnetic resonance imaging now provides a secure method of detection, proving the histopathological findings.

Treatment consists of surgical removal of the tumor mass. However, recurrences are common. In some cases with familial clustering an autosomal dominant inheritance of the disease could be proved.