Showing posts with label Cowden syndrome MRI. Show all posts
Showing posts with label Cowden syndrome MRI. Show all posts

Sunday, 29 December 2013

Lhermitte Duclos disease MRI


MRI Brain T2w images show a well demarcated hyper intense lesion in right cerebellum with striations ("corduroy" sign). Despite of its size results in little mass effect.

Lhermitte-Duclos disease (Dysplastic cerebellar gangliocytoma)

Synonyms: 
• Cowden syndrome (CS) ~ multiple hamartoma syndrome, multiple hamartoma-neoplasia syndrome.
o Hamartoma of cerebellum.
o Hamartoblastoma.
o Granule cell hypertrophy, granulomolecular hypertrophy.
o Diffuse ganglioneuroma of cerebellar cortex.
o Neurocytic blastoma.
o Myelinated neurocytoma.
o Purkingeoma.

Dysplastic cerebellar gangliocytoma (LD) is a rare tumour of cerebellum.
Grading WHO grade 1 tumor.
Varies in size and extent, always occur in cerebellum.

Imaging findings: 
Generally affects one hemisphere but commonly extends to vermis, as a well demarcated area of abnormal low density on CT / T2 hyper intensity on MRI with striations ("corduroy" or "tiger-striped" pattern).
No edema.
Usually little mass effect.
No restricted diffusion on MRI Diffusion.
No enhancement on post contrast. Very rarely mild enhancement.
MRS Reduced NAA, decreased to normal Choline, raised Lactate.

Histopathological findings: 
Gross pathologic and surgical features includes markedly enlarged cerebellar hemisphere/vermis with thick folia, Pale appearing mass.
Microscopic features includes widening of molecular cell layer ~ occupied by abnormal ganglion cells, Absence of Purkinje cell layer, Hypertrophy of granule cell layer, decreased volume of white matter.
Histologically may be confused with ganglion cell tumor

Clinical Presentation: 

Signs/symptom are often vague related to raised intracranial pressure, brainstem and cerebellar findings (cranial nerve palsies, ataxia), hydrocephalus.
Onset of symptoms most common during 3rd-4th decades of life
Age and Gender:
Any age, birth-60 years, more common between 30-40 years.
M = F / M >  F

LD is very rare, all patients must be screened for CS.
Cowden syndrome is a hereditary hamartoma-tumor syndrome ("phakomatosis") characterized by
1. LD in brain,
2. Mucocutaneous lesions,
3. Multiple hamartomas/neoplasias in breast/thyroid,
4. Gastrointestinal tract polyps,
5. Genitourinary malignancies,

Clinically CS include:
Macrocephaly,
Benign breast, skin lesions
Oral papillomas,
Benign thyroid lesions (adenomas),
Gastrointestinal tract polyps/hamartomas,
Cataracts,
Genitourinary neoplasias.

Treatment: 
Surgical resection in symptomatic patients
Borders of lesion blend into normal surrounding cerebellum may cause total resection difficult.