Neoplasms and Genetic syndrome Flashcards
Classification of brain tumours?
Gliomas
astrocytomas, oligodendrogliomas, ependymomas)
meningiomas, schwannomas
Brain tumours
Secondary
Common metastases
lung, breast, melanoma
Common Presentations
- Headaches (worse in the morning, with positional changes)
- Nausea/vomiting (raised ICP)
- Focal neurological deficits (e.g., hemiparesis, aphasia)
-Seizures
Key tumour types?
glioblastoma multiforme GBM
Meningioma
Pituitary adenoma
Glioblastoma Multiforme (GBM):
Aggressive, poor prognosis, ring-enhancing lesion on MRI
Meningioma
Extra-axial, often benign, “dural tail” sign on imaging
Diagnosis
Imaging: CT/MRI (MRI preferred for detailed structural evaluation)
Biopsy for histopathology (gold standard)
Mx of tumours?
Surgery: First-line for resectable tumours
Radiation therapy: Often used for residual disease
Chemotherapy: E.g., temozolomide for glioblastoma
Symptom control:
Corticosteroids for cerebral edema
Antiepileptics for seizure prophylaxis
Neurofibromatosis (NF)
NF1:
Autosomal dominant (mutation in NF1 gene)
Features: Cafe-au-lait spots, neurofibromas, Lisch nodules (iris hamartomas), optic gliomas
Associated risks: Learning difficulties, skeletal abnormalities (e.g., scoliosis)
Neurofibromatosis NF2
NF2:
Autosomal dominant (mutation in NF2 gene)
Features: Bilateral vestibular schwannomas, hearing loss, tinnitus, cataracts
Increased risk of meningiomas and ependymomas
Diagnosis
Neurofibromatosis
NF1: Clinical criteria (e.g., ≥6 cafe-au-lait spots, neurofibromas, or family history)
NF2: Genetic testing, MRI for vestibular schwannomas
Mx for NF ?
Multidisciplinary approach:
Regular monitoring (e.g., ophthalmology for optic gliomas, audiology for hearing loss)
Surgery for symptomatic tumours
Genetic counseling for family planning
Tuberous Sclerosis
- Pathophysiology
Autosomal dominant (mutations in TSC1 or TSC2 genes)
Causes widespread hamartomas affecting multiple organs
A 35-year-old presents with progressive hearing loss and bilateral vestibular schwannomas on MRI. Diagnosis?”
Answer: NF2
NF1: “CAFE SPOT”
Cafe-au-lait spots
Axillary freckles
Fibromas (neurofibromas)
Eye Lisch nodules
Skeletal abnormalities
Positive family history
Optic glioma
Tumours
Diagnosis of tuberous sclerosis
Major features: Facial angiofibromas, cortical dysplasias, retinal hamartomas
Minor features: Dental pits, rectal polyps
tuberous
Imaging:
MRI brain (for CNS involvement)
Renal ultrasound or MRI
Tuberous Sclerosis
Anti-epileptics for seizures (first-line for symptom control)
Everolimus (mTOR inhibitor) for SEGAs and renal angiomyolipomas
Surveillance:
Regular renal imaging
EEG for epilepsy monitoring
Multisystem monitoring with specialist teams
LMN neurone signs where is the lesion?
anterior horn of the spinal cord, peripheral nerve NMJ or muscle
LMN signs?
paralysis
atrophy / loss of muscle
fasciculations / muscle twitching
hyporeflexia / decreased absent reflexes
Riluzole
medication used in ALS
reduces release of glutamate
> primary excitatory neurotransmitter in CNS
parkinsons is a
reduction of dopaminergic neurones in the basal ganglia
LOss of dopaminergic neurones in the substanstia Nigra
Basal ganglia is a group of structures
coordinates movement
learning specific movement patterns
is Parkinson’s bilateral or unilateral?
worse on one side 4-6 hertz frequency
benign essential tremor
is worse with rest?
false
improves with rest
levodopa
synthetic dopamine
oral intake
combine with a peripheral decarboxylase inhibitor
> stops metabolims befor eit reaches brain
main side effect of levodopa?
dyskinesia
> muscle contraction abnormal
chorea
jerking random movements
how to manage the main side effect of levodopa?
amantadine
glutamate antagonist
COMT Inhibitors
metabolises levodopa in both the body and brain. Entacapone is taken with levodopa (and a decarboxylase inhibitor) to slow the breakdown of the levodopa in the brain. It extends the effective duration of the levodopa.
what is the role of cabergoline
dopamine agonists
mimic action dopamine in the basal ganglia
stimulates dopamine receptors
Huntingtons chorea
autosomal dominant genetic condition
trinucleotide repeat disorder
HTT gene on chromosome 4
trinucleotide repeat disorders
huntingtons
fragile X
spinocerebellar ataxia
myotonic dystrophy
friedrich ataxia
genetic anticipation.
successive generations have more repeats in gene
earlier age of onset
increased severity of disease
