Lhermitte–Duclos disease (LDD) (), also called dysplastic gangliocytoma of the cerebellum (DGC), is a rare, slowly growing

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

of the

cerebellum The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or eve ...

, a

gangliocytoma A ganglioglioma is a rare, slow-growing primary central nervous system (CNS) tumor which most frequently occurs in the temporal lobes of children and young adults. They are mixed cell tumors containing both neural ganglionic cells and neural gli ...

sometimes considered to be a

hamartoma A hamartoma is a mostly benign, local malformation of cells that resembles a neoplasm of local tissue but is usually due to an overgrowth of multiple aberrant cells, with a basis in a systemic genetic condition, rather than a growth descended fr ...

, characterized by diffuse

hypertrophy Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number. Although hypertro ...

of the granular layer of the cerebellum. It is often associated with Cowden syndrome. It was described by

Jacques Jean Lhermitte Jacques Jean Lhermitte () (20 January 1877 – 24 January 1959) was a French neurology, neurologist and Neuropsychiatry, neuropsychiatrist. Early life and education Lhermitte was born in Mont-Saint-Père, Aisne, son of Léon Augustin Lhermit ...

and P. Duclos in 1920.

Signs and symptoms

Main clinical signs and symptoms include: *

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

* movement disorders *

tremor A tremor is an involuntary, somewhat rhythmic muscle contraction and relaxation involving neural oscillations, oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the h ...

* visual disturbances * abnormal

EEG Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neoc ...

Diplopia Diplopia is the simultaneous perception of two images of a single object that may be displaced in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occ ...

Patients with Lhermitte–Duclos disease and Cowden's syndrome may also have multiple growths on skin. The tumor, though benign, may cause neurological injury including abnormal movements. MICROSCOPY (lhermitte-duclos disease) 1>Enlarged circumscribed cerebellar folia 2>internal granular layer is focally indistinct and is occupied by large ganglion cells 3>myelinated tracks in outer molecular layer 4>underlying white matter is atrophic and gliotic

Pathophysiology

In Lhermitte–Duclos disease, the

cerebellar cortex The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or e ...

loses its normal architecture, and forms a

in the cerebellar hemispheres. The tumors are usually found on the left cerebellar hemisphere, and consist of abnormal hypertrophic ganglion cells that are somewhat similar to

Purkinje cells Purkinje cells or Purkinje neurons, named for Czech physiologist Jan Evangelista Purkyně who identified them in 1837, are a unique type of prominent, large neuron located in the cerebellar cortex of the brain. With their flask-shaped cell bo ...

. The amount of

white matter White matter refers to areas of the central nervous system that are mainly made up of myelinated axons, also called Nerve tract, tracts. Long thought to be passive tissue, white matter affects learning and brain functions, modulating the distr ...

in the cerebellum is diminished. Like cowden syndrome, patients with Lhermitte–Duclos disease often have mutations in enzymes involved in the

Akt/PKB signaling pathway The Akt signaling pathway or PI3K-Akt signaling pathway is a signal transduction pathway that promotes survival and growth in response to extracellular signals. Key proteins involved are PI3K (phosphatidylinositol 3-kinase) and Akt (protein kinase ...

, which plays a role in cell growth. Mutation in PTEN gene on chromosome no. 10q leads to increased activity of AKT and mTOR pathways, and patients should be tested for these mutations because they may be at risk of other tumors and cancers in other parts of the body.

Diagnosis

Treatment

Treatment is not needed in the asymptomatic patient. Symptomatic patients may benefit from surgical debulking of the tumor. Complete tumor removal is not usually needed and can be difficult due to the tumor location.

Epidemiology

Lhermitte–Duclos disease is a rare entity; approximately 222 cases of LDD have been reported in medical literature. Symptoms of the disease most commonly manifest in the third and fourth decades of life, although it may onset at any age. Men and women are equally affected, and there is not any apparent geographical pattern.

History

The disease was first described in 1920 by Lhermitte and Duclos.

References

External links

*
MedPix: Lhermitte-Duclos
�� Radiology and Pathology {{DEFAULTSORT:Lhermitte-Duclos Disease Deficiencies of intracellular signaling peptides and proteins Rare diseases Central nervous system disorders Genodermatoses