Oncology Flashcards
What is the definition of an oncological emergency?
-An acute medical problem related to cancer or it’s treatment which may result in serious morbidity or mortality if not treated quickly
What are the categories of oncological emergency?
- Metabolic
- Structural/obstructive
- Treatment related
What are the main oncological emergencies?
- Hypercalcaemia
- SIADH
- Spinal cord compression
- SVC obstruction
- Raised ICP
- Airway obstruction
- Neutropenic sepsis
- Anaphlaxis
- Tumour lysis syndrome
- Extravasation
- Tamponade
What is the definition of hyercalcaemia?
-Serum corrected calcium >2.6mmol/L
What are the causes of hypercalcaemia?
- Direct bone destruction ie bone tumour, bony mets, myeloma
- Parathyroid hormone related protein
- Non-cancer causes ie primary hyperparathyroidism
- Sarcoidosis
- Vit D intoxication
- Lithium
- Dehydration
What is the cause of hypercalcaemia if PTH is high normal or raised?
-Hyperparathyroidism
What are the possible causes if PTH is low or low/normal?
- Malignancy
- Drugs ie thiazides, high dose vit d, lithium
- Thyrotoxicosis
- Adrenal insufficiency
- Sarcoid or TB
How does hypercalcemia present? (useful rhyme)
-STONES, BONES, GROANS, MOANS
What are the GI symptoms caused by hypercalcaemia?
- Abdominal pain
- Constipation
- Nausea/vomiting
- Anorexia
- Weight loss
- Dehydration
What are the Gu symptoms caused by hypercalcaemia?
- Renal stones
- Renal failure
- Polyuria
- Polydipsia
What are the neuro symptoms caused by hypercalcaemia?
- Fatigue
- Weakness
- Confusion
What are the psych symptoms caused by hypercalcaemia?
-Depression
What investigations should be done for hypercalcaemia?
- Corrected calcium levels
- ECG (shortened QT level)
- Chloride levels
- ABG
- K+
- Phosphate
- Alk phos
- PTH
- CXR (sarcoidosis)
- 24hr urinary calcium excretion (for familial hypocalciuric hypercalcaemia)
What suggests that hypercalcaemia is caused by malignancy?
- Low albumin
- Low chloride
- Alkalosis
- Low potassium
- Raised phosphate
- Raised alk phos
- PTH normal
What are side effects of bisphosphonates?
- Flu like symptoms
- Oesophagitis
- Osteonecrosis of the jaw
- Bone pain
- Myalgia
- Reduced phosphate levels
- Nausea and vomiting
What drug can be used for persistent/relapsed hypercalcaemia of malignancy?
- Denosumab
- Chemotherapy
What is SIADH?
-Syndrome of inappropriate ADH secretion
>excess ADH
What does ADH do?
-Stops urine output by acting on the collecting duct
>water retention and low serum sodium
>high urine osmolarity
What are the malignant causes of SIADH?
-Paraneoplastic syndrome >SCLC >Pancreatic -NHL -Hodgkins lymphoma Prostate
How does SIADH present?
- Fatigue
- N + V
- Confusion
- Coma
Investigations for SIADH?
- Serum sodium (low, dilutional)
- Plasma osmolarity (low)
- Urine sodium (high, concentrated)
- Urine osmolarity (high)
- Look for underlying cause ie CT scan
Management of SAIDH?
Fluid restirct (0.5-1l in 24hrs)
- Demeclocycline (abx which is known to cause reversible nephrogenic diabetes insipidus)
- ADH receptor antagonists
How is SIADH managed in an emergency? (ie coma/fitting)
-Slow infusion of NaCl 1.8%
Why is it important to correct SIADH slowly?
-Avoid precipitating central pontine myelinolysis
damage to the myelin sheath of the nerve cells in the Pons
What is spinal cord compression caused directly by malignancy?
- Pressure from tumour in between the vertebral bodies
- Collapsed vertebral bodies on the spinal cord or cauda equina
Which spinal nerves are responsible for the knee and ankle jerk reflexes?
- Knee jerk: L3, L4
- Ankle jerk: S1
What are the causes of spinal cord compression?
- Malignancy (2ndry is most common)
- Trauma
- Disc prolapse
- Inflammatory disease
- Spinal infection
- Epidural or subdural haematoma
Which types of cancer most commonly cause spinal cord compression?
- Breast
- Lung
- Thyroid
- Prostate
- Kidney
- Bowel
- Melanoma
- Myeloma
- Lymphoma
How does spinal cord compression present?
- Back pain
- Radicular pain (radiates to the lower extremity of that nerve root)
- Leg or arm weakness below level of compression
- Difficulty walking
- Sensory loss below level of compression
- Bladder and bowel dysfunction
- ED
- Abnormal neurological examination
On a neurological examination, what would LMN and UMN signs be for someone with a spinal cord compression?
- UMN: signs below the level of the compression
- LMN: signs at the level of examination
How is spinal cord compression managed acutely?
- Analgesia
- High dose corticosteroids ie dexamethasone 8mg BD
- PPi cover whilst on steroids
- Bed rest if spinal instability
- Definitive treatment depends on site and extent of lesions and fitness
When would surgery be indicated for spinal cord compression?
-Single area of SCC - decompress then radiotherapy (allows spinal column stability)
What is the role of radiotherapy in management of spinal cord compression?
- Shrink the tumour
- Prevents deterioration of neurology
- Pain control
Other methods to treated spinal cord compression?
- Chemotherapy
- Hormone deprivation (in newly diagnosed prostate cancer causing mets)
- Bisphosphonates for bone pain
- VTE prophylaxis
- Pressure sore prevention
- Manage bladder and bowel dysfunction
What is superior vena cava obstruction?
-Compression, invasion or occasionally intra-luminal obstruction of the SVC
Describe the anatomy of the SVC?
- Provides venous drainage for the head, neck upper limbs and upper thorax
- From right atrium to the junction of the right and left innominate veins
- Surrounded by the sternum, trachea, right bronchus, aorta, PA, perhihilar and peritracheal lymph nodes
- IF svc obstructed, collateral pathways drain blood to return to the RA
What are the main causes of SVCO?
- Small cell lung cancer
- Non-small cell lung cancer
- Lymphoma
What are some other causes of SVCO?
- Thymoma
- Germ cell tumours
- Thrombus
- Direct tumour invasions
- Pressure outside of the vessel
Symptoms of SVCO?
- Dyspnoea
- Chest pain at rest
- Cough
- Neck, face and arm swelling - including conjunctival and periorbital oedema
- Dizziness
- Headache - worse in the morning
- Visual disturbance
- Syncope
Signs of SVCO?
- Visual compensatory collaterals ie dilated veins over neck, arms, anterior chest wall
- Oedema of upper torso, arms, neck and face
- Severe resp. distress
- Cyanosis
- Engorged conjunctiva
- Convulsions and coma
What is Pemberton’s sign?
-Raising arms to touch over head
-If develop cyanosis, worsening SOB, or facial congestion
+ve for SVCO
Investigations for SVCO?
- Clinical diagnosis
- CXR - wide mediastinum, mass on right side of heart
- CT
- Doppler studies
- Invasive contrast-venography
How is SVCO managed?
- Symptomatic relief ie elevation of head and oxygen therapy
- Steroids 8mg BD po
- Endovascular stenting
- ?Anticoagulation
- Ultimate treatment depends on cause ie radio, chemo
What is the normal value for intracranial pressure?
-Normal ICP <15mmHg
Causes of raised ICP?
- Primary metastatic tumours
- Head injury
- Haemorrhage (subdural, extradural, subarachnoid, intracerebral, intraventricular)
- Infection
- Hydrocelphalus
- Cerebral oedema
- Status epilepticus
- Idiopathic intracranial hypertension
How does raised ICP present?
- Headache (worse when coughing, in morning, leaning forwards)
- Vomiting
- History of trauma
- Reduced GCS - drowsiness, irritability, coma
- Falling pulse
- Rising BP
- Cheynes-stokes respiration (deeper and quicker breathing followed by apnoeic episodes)
- Pupil changes
- Visual disturnaces
- Papilloedema
What investigations need doing for raised ICP?
- Fundoscopy
- U&E, FBC, LFT, glucose, clotting, blood cultures
- Consider tox screen
- CXR
- CT head
- LP if safe: measure opening pressure
Immediate management for raised ICP?
-ABCDE
-Correct hypotension
-Elevate bed to 30-40*
-Restrict fluids: 1.5l/day
-Diagnose and treat underlying cause
>?meningococcal rash, previous cancer
What’s the role of mannitol in raised ICP?
-Osmotic agent used to suck out water from the brain
>20% solution IV over 10-20 mins
-May lead to rebound raised ICP after prolonged use
What is the role off corticosteroids in raised ICP?
- Only useful if raised ICP is due to cancer
- Dexamethasone 10mg IV
- Reduces oedema surrounding tumours
What are the 3 main herniation syndromes associated with raised ICP?
- Uncal herniation
- Cerebellar tonsil herniation
- Subfalcian (cingulate) herniation
What is uncal hernation?
- Lateral supratentorial mass causes the uncus to push against the midbrain
- 3rd nerve palsy: dialted ipsilateral pupil, ophthalmoplegia
- followed by contralateral hemiparesis due to pressure on cerebral peduncle
Why does uncal herniation result in a coma?
-Coma is a result of the pressure on the ascending reticular activation system in the midbrain
What is cerebellar tonsil herniation?
-Caused by increased pressure in the posterior fossa > forces the cerebellar tonsilts through the foramen magnum
What are the symptoms/signs of cerebellar tonsil herniation?
- Ataxia
- 6th nerve palsies
- Upgoing plantars
- LOC
- Irregular breating
- Apnoea
What is subfalcian (cingulate) herniation?
- Caused by a frontal mass
- The cingulate gyrus is forced under the rigid falx cerebri