|Lhermitte Duclos Disease
| Primary CNS Lymphoma (PCNSL)
- Poor prognosis except in Grade I
- Exposure to ionising radiation
- Neurofibromatosis type 1 and 2 (glioma)
- Tuberous sclerosis (astrocytoma)
- Li Fraumeni (malignant glioma)
- Turcot syndrome (malignant glioma)
- Faulty tumour suppressor genes
- Amplification of EGFR gene
- Inactivation of p53 gene
Classification Low to High Grade
- Grade I Benign
- Grade II Diffuse
- Grade III Anaplastic
- Grade IV Glioblastoma multiforme
Difficulties of Diagnosis Tumour vs Stroke
|Day 1: admitted suspected stroke but some atypical features.|
Patient improved and discharged home
|Day 15: clinical worsening|
|Day 18: clinical worsening|
|Day 21 with contrast|
Differential of Butterfly tumour across the Corpus: pre and post contrast
- High grade Astrocytoma, usually a Glioblastoma (WHO grade IV)
- Primary CNS lymphoma (consider HIV)
- Cerebral Toxoplasmosis (consider HIV)
Low grade Astrocytomas
- These tumours are found in the Cerebrum and cerebellum (commoner in children), Hypothalamus, Optic nerve, Chiasm, Pons
- Grade I Benign: seen in childhood with excellent prognosis after removal. Also called juvenile pilocytic astrocytomas or subependymal giant cell astrocytoma. Pilocytic have spindle-shaped cells. May involve the cerebellum. Well demarcated from the brain.
- Grade II: Astrocytoma has a prognosis of 5-6 years. Intermediate in histology. Well-differentiated slow-growing tumour. Young Adults affected.
- MRI may show sharply demarcated pilocytic tumours with hypointense T1 and hyperintense T2. Fibrillary tumours are less well-demarcated. Maybe cyst formation and calcium. May be limited contrast enhancement.
- As mentioned above some Grade I tumours in children can be resected with an excellent prognosis. In the remainder, Survival may be up to 5-6 years. Some tumour resection especially of cystic lesions. Total excision may be possible in some with improved survival. With time low-grade gliomas become more malignant. Radiotherapy may also be given. Side effects of early radiation may be later dementia and hypopituitarism. A watch and wait strategy may be adopted for slow-growing tumours. Seizure management.
High grade astrocytomas
- Includes Grade III Anaplastic and Grade IV Glioblastoma multiforme (malignant aggressive tumours) which form 20% of all intracranial tumours. Mean age 56-60 years old. Grade III has a median survival of less than 3 years and Grade IV less than 1 year.
- Derived from glial cells - astrocytes. Most arise in white matter and infiltrate the brain. Grey, reddish-brown appearance. May contain a haemorrhage. Surrounding oedema.
- Found mainly in the Cerebrum most commonly and Brainstem, cerebellum, cord. CT/MRI shows tumour mass +/- bleeding, distortion, midline shift which enhances with contrast
- Only 10% survive beyond 2 years. Prognosis is very poor. Palliation, Dexamethasone 4 mg every 4-6 hours. Anticonvulsants for seizures. Cranial irradiation and chemotherapy may extend life in some cases