Oncological Emergencies

Question 1

what is malignant cord compression?

Answer 1

radiological evidence of indentation of the thecal sac secondary to cancer

Question 2

which cancers are associated most bone mets leading to malignant cord compression?

Answer 2

lung
breast
kidney
prostate
thyroid

Question 3

where in the spine do majority of malignant cord compression occur?

Answer 3

60% thoracic
30% lumbar
10% cervical

Question 4

clinical features of cord compression?

Answer 4

• pain (severe, progressive)
• weakness (typically symmetrical)
• UMN lesions (increased tone, hyperreflexia, upgoing plantars)

Question 5

difference in features between cord compression and cauda equina?

Answer 5

cord compression: back pain, paralysis, hyperreflexia, +ve babinskis

cauda equina: back pain radiculopathy, reduced anal tone, saddle anaesthesia, paralysis hyporeflexia, hypotonia

Question 6

Ix to diagnose cord compression

Answer 6

MRI = gold standard

Question 7

Mx of cord compression?

Answer 7

• analgesia
• VTE prophylaxis
• high dose dexamethasone
• radiotherapy as adjuvant to surgery (or stand alone if unable to undergo surgery)

Question 8

what is malignant hypercalcaemia?

Answer 8

serum calcium >2.6mmol/L, secondary to malignant process

Question 9

what are the most common malignancies associated with hyperparathyroidism?

Answer 9

breast cancer
multiple myelom a
lymphoma
lung cancer

Question 10

what are the 3 main mechanisms that cause malignant hypercalcaemia?

Answer 10

osteolytic mets
PTH - related protein (PTHrP) secretion
increased 1,25-dihydroxyvitamin D production

Question 11

clinical features of malignant hypercalcaemia?

Answer 11

‘stones, bones, thrones, abdo groans, psychiatric mones’

renal stones
bone pain
polyuria
abdo pain
psychiatric features

Question 12

Ix to diagnose malignant hypercalcaemia?

Answer 12

• serum calcium level calcium level >2.6
• identification of underlying cancer

(measure PTH as in malignant hypercalcaemia the PTH should be suppressed compared to primary hyperparathyroidism)

Question 13

Mx of malignant hypercalcaemia?

Answer 13

IV rehydration, calcitonin and bisphosphonate therapy

admit to hosp if serum calcium >3mmol/L

Question 14

what is neutropenic sepsis ?

Answer 14

fever >38 degrees OR features of sepsis in a pt with pt w/ neutrophil count of <0.5

Question 15

causes of neutropenia?

Answer 15

genetic: congenital neutropenia, chediak-higashi syndrome
acquired: malignancy, infections, drugs, autoimmune

Question 16

clincial features of neutropenic sepsis?

Answer 16

signs of infection: (e.g. pneumonia or UTI)

• temperature
• acute confusion
• tachypnoea
• low BP
• tachycardia
• low urine output

Question 17

Ix to diagnose neutropenic sepsis?

Answer 17

Ix to identify source of infection + evidence of organ dysfunction and complications

• bedside
• bloods
• cultures
• imagine e.g. CXR, LP, ECHO

Question 18

Mx of neutropenic sepsis?

Answer 18

SEPSIS 6:
1. give 02
2. IV access, take bloods
3. give IV abx
4. give IV fluids
5. measure urine output
6. measure lactate

Question 19

what is malignant SVCO?

Answer 19

obstruction to the flow of blood through the superior vena cava secondary to cancer (from direct tumour growth or lymphadenopathy)

Question 20

most common cancers to cause SVCO?

Answer 20

lung carcinoma (70-80%)
non hodgkins lymphoma (10%)

less common:
- thymic
- breast
- mediastinal germ cell tumours

Question 21

clinical features of SVCO?

Answer 21

dyspnoea, facial swelling, head fullness, cough, dysphagia, worsening on bending forward, facial plethora, upper limb oedema , distended neck and chest well veins
+ve pembertons sign

Question 22

Ix to diagnose SVCO?

Answer 22

CXR - showing abnormality e.g. mediastinal widening or malignant pleural effusion

CT = diagnostic

then diagnose malignancy: tissue biopsy + staging CT

Question 23

Mx of SVCO?

Answer 23

conservative: elevation of head and neck, o2 titrated to sats

stenting, radiotherapy and chemo = main tx but dexamethasone can be to reduce swelling

Question 24

what is tumour lysis syndrome?

Answer 24

metabolic disturbances arising from breakdown of malignant cells following initiation of treatment for malignancy

Question 25

what electrolyte abnormalities do you get in tumour lysis syndrome?

Answer 25

hyperkalaemia hyperphosphataemia hypocalcaemia hyperuricaemia

Question 26

consequences of electrolyte disturbance in tumour lysis syndrome?

Answer 26

AKI, arrythmias, sudden death

Question 27

what type of malignancy is tumour lysis syndrome common in?

Answer 27

haematological malignancy

Question 28

what factors are associated with developing tumour lysis syndrome?

Answer 28

- high proliferation rate - chemosensitivity - large tumour burden - pre existing metabolic disturbances - renal impairment

Question 29

clinical features of tumour lysis syndrome?

Answer 29

(tend to occur within first 72 hours following initiation of treatment) lethargy n+v diarrhoea anorexia muscle cramps syncope pruritus arthritis fluid overload heamaturia tetany + parasthesia bronchospasm (wheezing)

Question 30

what Ix are done to diagnose tumour lysis syndrome?

Answer 30

renal function, electrolytes, serum urate +/- urine dip urine microscopy serum lactate lactate dehydrogenase ECG cardiac monitoring

Question 31

what monitoring needs to be done if a pt is at high risk of tumour lysis syndrome

Answer 31

renal function, electrolytes and serum urate regularly

Question 32

how is the diagnosis of tumour lysis syndrome made?

Answer 32

based on the cairo-bishop definition lab diagnosis: 2 or more needed - uric acid >476micromol/L - K+ > 6mmol/L - phosphate >1.45mmol/L - calcium <1.75mmol/L AND clin diagnosis: 1 or more needed - serum creatinine >1.5 upper limit normal - cardiac arrythmia / sudden death - seizure

Question 33

what prophylaxis can be given to patient who are at high risk of developing tumour lysis syndrome?

Answer 33

oral or IV hydration allopurinol rasburicase

Question 34

how is tumour lysis syndrome managed?

Answer 34

hyperphosphataemia -> hydration + diet restriction hyperkalaemia -> IV calcium gluconate, insulin/dextrose infusion and neb salbutamol hypocalcaemia -> dont treat unless symptomatic in which give IV replacement renal impairement -> fluids rehydration, adjustment of drug doses, possibly haemofiltration