Brain Tumours – GCC Nurse Clinical Guide

Overview

Types & Grading

Presentation & ICP

Management

GCC Context

MCQ Practice

🧠 Brain Tumours — Overview

Brain tumours are abnormal cell growths within the brain or its surrounding structures. They may be primary (arising from brain tissue) or secondary/metastatic (arising from cancers elsewhere in the body).

Secondary (metastatic) brain tumours are MORE COMMON than primary brain tumours — approximately 10× more frequent. Common primaries that metastasize to brain: lung (most common), breast, melanoma, colorectal, renal cell carcinoma.

Incidence

Primary brain tumours: ~7 per 100,000 population/year
GBM (glioblastoma multiforme): most common malignant primary brain tumour in adults; median survival ~15 months with treatment
Peak incidence of GBM: 55–75 years
Meningioma: most common benign brain tumour; more common in women; often incidental finding

Risk Factors

Established Risk Factors

Ionising radiation (therapeutic cranial irradiation) — only proven environmental risk factor for most brain tumours
Genetic syndromes: NF1/NF2 (neurofibromatosis), Li-Fraumeni, Turcot, Gorlin syndrome
Immunosuppression (HIV, post-transplant) → CNS lymphoma

NOT Proven Risk Factors

Mobile phone use (controversial — no definitive causal link established)
Power lines, wifi radiation
Head trauma

📊 Common Brain Tumour Types & WHO Grading

Tumour Type	WHO Grade	Key Features	Prognosis
Pilocytic astrocytoma	Grade 1	Commonest brain tumour in children; cerebellum; cystic with mural nodule	Excellent — often cured by surgery
Meningioma	Grade 1–3	Most common benign; extra-axial (outside brain parenchyma); women > men; often asymptomatic	Excellent if grade 1; recurrence risk grade 2–3
Low-grade astrocytoma / oligodendroglioma	Grade 2	Young adults; slow-growing; seizures common first symptom; IDH mutation typical	Median survival 5–10 years
Anaplastic glioma	Grade 3	Rapid growth; significant oedema	Median survival 2–3 years
Glioblastoma (GBM)	Grade 4	Most aggressive; "butterfly glioma" crosses corpus callosum; ring-enhancing with central necrosis on MRI; IDH wild-type; older adults	Median survival 12–18 months
Medulloblastoma	Grade 4	Most common malignant brain tumour in CHILDREN; posterior fossa/cerebellum; obstructive hydrocephalus	60–80% 5-year survival with treatment
Acoustic neuroma (vestibular schwannoma)	Grade 1	CN VIII; unilateral sensorineural hearing loss + tinnitus + vertigo; bilateral = NF2	Benign; surgery/radiosurgery
CNS lymphoma (PCNSL)	Grade 4	Immunocompromised (HIV); periventricular; ring-enhancing; EBV-positive; exquisitely steroid-sensitive (steroids can make lesions disappear → biopsy BEFORE steroids)	Poor without treatment; good response to methotrexate + rituximab

CNS Lymphoma and Steroids: NEVER give dexamethasone to a patient with suspected CNS lymphoma before biopsy — steroids cause lymphoma cells to die (cytolytic), making the biopsy non-diagnostic. "Steroids before biopsy = missed diagnosis."

🚨 Clinical Presentation & Raised ICP

Symptoms of Brain Tumours

Raised ICP Symptoms

Headache — worst in morning, improved by sitting up, worsened by Valsalva (coughing, bending)
Nausea and vomiting (especially on wakening)
Papilloedema (blurred vision, visual obscurations)
Declining consciousness
Bradycardia + hypertension (Cushing's triad — late sign of coning)

Focal Neurological Deficits (location-dependent)

Frontal lobe: personality change, executive dysfunction, gait disturbance
Temporal lobe: memory impairment, language (dominant hemisphere), visual field defects
Parietal lobe: hemisensory loss, neglect, dyspraxia
Occipital lobe: visual field defects
Cerebellum: ataxia, dysarthria, nystagmus
Brainstem: cranial nerve palsies, weakness, respiratory pattern change

Cushing's Triad — Late Warning Sign of Cerebral Herniation

Cushing's Triad (LATE sign — imminent herniation):
1. Hypertension (rising BP)
2. Bradycardia
3. Irregular/slow respiratory pattern
This triad indicates the brainstem is being compressed — EMERGENCY management required immediately.

Herniation Syndromes

Uncal herniation (transtentorial): Temporal lobe herniates through tentorium → compresses CN III → ipsilateral fixed dilated pupil ("blown pupil") + contralateral hemiplegia
Tonsillar herniation: Cerebellum/cerebellar tonsils herniate through foramen magnum → compresses brainstem → respiratory arrest

Seizures in Brain Tumours

25–30% of brain tumour patients present with seizures
Focal seizures (with or without secondary generalisation) most common
Low-grade tumours (especially oligodendrogliomas) have higher seizure incidence than GBM
Management: levetiracetam (Keppra) — most commonly used; no routine seizure prophylaxis in tumour patients WITHOUT seizure history (EANO guidelines)

💊 Brain Tumour Management

Raised ICP — Emergency Management

Elevate head of bed 30–45° (reduces venous pooling)
Avoid neck compression (tight collar) — prevents venous outflow obstruction
Oxygen — maintain SpO₂ ≥94%; avoid hypercarbia (CO₂ dilates cerebral vessels, increases ICP)
Dexamethasone 8–16 mg IV — reduces peritumoral oedema (acts over hours to days)
Mannitol 20% 0.5–1 g/kg IV over 20–30 min — osmotic diuresis for acute ICP crisis; monitor urea and osmolality
Hypertonic saline (3%) — alternative/adjunct to mannitol
Intubation and controlled hyperventilation (PaCO₂ 4.0–4.5 kPa) — temporary cerebral vasoconstriction; bridge to definitive treatment
Urgent neurosurgical review for surgical decompression

Dexamethasone and brain tumours: The drug of choice for peritumoral oedema. Standard dose: 4–8 mg BD. In acute severe ICP: 16 mg IV loading then 4 mg QDS. Dexamethasone reduces oedema but does NOT treat the tumour itself. Monitor blood glucose (steroid-induced hyperglycaemia).

EXCEPTION: CNS lymphoma — withhold steroids until biopsy confirmed.

Treatment Modalities

Treatment	Indication	Notes
Surgical resection	GBM, most solid tumours (where accessible)	Goal: maximal safe resection; preserves eloquent cortex; fluorescence-guided surgery (5-ALA) for GBM
Radiotherapy	Post-surgical adjuvant; palliative; primary in inoperable tumours	Whole brain RT for multiple metastases; stereotactic radiosurgery (Gamma Knife) for 1–4 metastases
Chemotherapy	GBM: temozolomide (Stupp protocol); Medulloblastoma; PCNSL: methotrexate-based	GBM: concurrent and adjuvant temozolomide + radiotherapy = Stupp protocol; DNA methylation (MGMT) predicts response
Immunotherapy / targeted therapy	Specific molecular targets (IDH inhibitors, BRAF V600E for selected gliomas)	Bevacizumab for recurrent GBM (anti-VEGF)

Nursing Care Priorities

Neurological observation: GCS, pupil responses, limb power every 1–4 hours (frequency per clinical status)
Seizure precautions: bed rails up, padded environment, IV access patent, seizure rescue meds at bedside (lorazepam)
Fall prevention: focal deficits increase fall risk; regular orientation checks in confused patients
Blood glucose monitoring: dexamethasone causes significant hyperglycaemia; BGL QDS minimum
Steroid side effects education: moon face, weight gain, mood changes, insomnia (give last dose before 6pm)
VTE prophylaxis: brain tumour patients at HIGH risk of DVT/PE; LMWH prophylaxis recommended unless active bleeding risk
Psychological support: devastating diagnosis; connect with palliative care, chaplaincy, social work

🌍 GCC-Specific Context

Neuro-Oncology Services in GCC ▼

Dedicated neuro-oncology programmes at: KFSH Riyadh/Jeddah, King Abdulaziz Medical City, Cleveland Clinic Abu Dhabi, Hamad Medical Corporation Doha, Sultan Qaboos University Hospital
Gamma Knife stereotactic radiosurgery available at major GCC centres for brain metastases
MDT (multidisciplinary team) approach with neurosurgery, neuro-oncology, radiation oncology, neuropathology, neuroradiology, palliative care
Fluorescence-guided surgery (5-ALA) for GBM increasingly used at tertiary GCC centres
Intraoperative MRI available at selected GCC hospitals for maximal safe resection

Cultural Considerations in End-of-Life Neuro-Oncology ▼

Brain tumour diagnosis (especially GBM) carries a poor prognosis — end-of-life conversations must be handled with cultural sensitivity in GCC
Islamic perspective: truth-telling in diagnosis is generally supported but delivery must be compassionate; family involvement is expected and culturally appropriate
Many GCC patients and families prefer initial disclosure to family (not directly to patient) — respect cultural norms while ensuring patient autonomy
Advance care planning discussions should involve Islamic scholars/chaplains at hospital when appropriate
Palliative care teams in GCC hospitals are increasingly trained in Islamic bioethics and culturally sensitive end-of-life communication
Dexamethasone withdrawal at end of life: gradual reduction (not abrupt cessation) to prevent adrenal crisis in long-term users

SCFHS / DHA / QCHP Exam Focus ▼

Secondary brain tumours are MORE common than primary (lung, breast, melanoma most common sources)
GBM (Grade 4): most common malignant primary; butterfly pattern on MRI; worst prognosis
Meningioma: most common benign; extra-axial; more common in women
Medulloblastoma: most common malignant brain tumour in CHILDREN; cerebellum; obstructive hydrocephalus
CNS lymphoma: NEVER give dexamethasone before biopsy — will destroy lymphoma cells and give false-negative biopsy
Cushing's triad: hypertension + bradycardia + irregular breathing = late sign of coning — EMERGENCY
Raised ICP management: HOB 30–45°, O₂, dexamethasone (peritumoral oedema), mannitol (acute crisis)
Dexamethasone side effect: hyperglycaemia — monitor blood glucose QDS
Give dexamethasone last dose before 6pm — prevents insomnia
Brain tumour patients at high VTE risk — LMWH prophylaxis unless active bleeding

📝 MCQ Practice

1. A 62-year-old man with known GBM on dexamethasone is brought in with sudden vomiting, GCS 13 (E3V4M6), and a left dilated non-reactive pupil. His BP is 195/110 and HR is 48 bpm. What does the pupil finding indicate and what is the immediate priority?

✅ B — A dilated fixed left pupil with declining GCS + Cushing's triad (hypertension + bradycardia) = left uncal herniation (temporal lobe herniating through tentorium, compressing ipsilateral CN III). This is a neurosurgical emergency. Immediate IV mannitol 0.5–1 g/kg + controlled hyperventilation + urgent neurosurgery review.

2. An immunocompromised HIV patient with CD4 80 cells/µL presents with headache and confusion. MRI shows a periventricular ring-enhancing lesion. The medical team wants to start dexamethasone before biopsy. What should the nurse communicate?

✅ B — In immunocompromised patients, CNS lymphoma is high on the differential. Steroids are cytolytic for lymphoma cells — dexamethasone before biopsy can cause lesions to shrink or disappear, rendering the biopsy non-diagnostic (false negative). Always aim for biopsy BEFORE dexamethasone unless the patient is critically herniated.

3. A patient with a brain tumour is started on dexamethasone 4 mg four times daily. Which monitoring is MOST important?

✅ C — Dexamethasone causes dose-dependent hyperglycaemia (steroid-induced diabetes). Blood glucose should be monitored at minimum QDS (4× daily). Insulin sliding scale may be required. Other important monitoring: BP (steroid hypertension), fluid balance, mood/behaviour changes, gastric protection (PPI).

4. Which brain tumour is the MOST COMMON malignant brain tumour in children?

✅ C — Medulloblastoma is the most common malignant brain tumour in children. It arises in the posterior fossa (cerebellum), commonly causing obstructive hydrocephalus (headache, vomiting, unsteady gait, papilloedema). GBM is the most common malignant primary in ADULTS. Meningioma is the most common overall brain tumour but benign.