Oncological emergencies Flashcards
What is the definition of neutropenic sepsis?
- Temp. >38 C or signs/symptoms of sepsis
- Neutrophil count <0.5 x10^9/L
Why might some patients with neutropenic sepsis not present with a fever?
- inability to mount inflammatory response e.g. on steroids
At what point after a chemotherapy course are patients most at risk of neutropenic sepsis?
5-10 days after last dose of chemo when neutrophil count reaches its lowest level.
A 38 year old lady who has recently had chemo. for breast cancer presents to rapid access cancer clinic with a fever and feeling generally unwell. What is your immediate management?
- Start IV TAZOCIN asap (4.5g 6 hrly) - or IV meropenem if penicillin allergy.
- Blood cultures (from all lumens of Hickmann line + peripheral vein)
- MSU + swabs from any Exit site or other infected foci
- Bloods: FBC + CRP + UEs + LFTs +/- ABG (glucose + lactate)
Review at 48-72 hrs.
A 47 year old man presents with nausea, vomiting, muscle cramps and palpitations. He has recently been diagnosed with ALL and is on day 3 of his 1st cycle of chemo. What is the likely diagnosis? What are the abnormalities seen in this condition?
Tumour lysis syndrome.
Excess cell lysis results in increased release of:
- uric acid
- potassium
- phosphate - this precipitates with calcium to form calcium phosphate, causing hypocalcaemia
Suggest possible risk factors for the development of TLS
- haematological malignancies - lymphoma and leukaemia, esp. Burkitt’s lymphoma and ALL
- recent chemo. usually 3-7 days after start
- high tumour burden
- chemosensitive tumours
- aggressive tumours
- pre-existing renal compromise
A 47 year old man presents with nausea, vomiting, muscle cramps and palpitations. He has recently been diagnosed with ALL and is on day 3 of his 1st cycle of chemo. Which investigations would you perform?
- ECG
2. Bloods: UEs, calcium, phosphate
How would you attempt to prevent TLS in a patient undergoing chemotherapy?
- Pre-hydration + vigorous hydration throughout Tx
- Monitoring of electrolytes + fluid balance
- ALLOPURINOL or 1 dose IV RASBURICASE if high risk
What is the MOA of allopurinol and rasburicase?
- Allopurinol: xanthine oxidase inhibitor that inhibits catabolism of purine to uric acid
- Rasburicase: synthetic urate oxidase that degrades uric acid to water-soluble allantoin
A 47 year old man presents with nausea, vomiting, muscle cramps and palpitations. He has recently been diagnosed with ALL and is on day 3 of his 1st cycle of chemo. His blood results show raised serum uric acid, potassium and phosphate with low calcium. His ECG shows peaked T waves with a prolonged QTc. How would you manage him?
1. Continuous ECG and UO monitoring Hyperuricaemia: 2. Aggressive hydration (exc. if renal failure or oliguria) 3. IV rasburicase Hyperkalaemia: 4. 10 ml 10% calcium gluconate IV 5. Insulin-glucose IV infusion +/- nebulised salbutamol Hyperphosphataemia: 6. phosphate binders Hypocalcaemia: 7. calcium gluconate
Describe the 2 main ways malignancy can cause spinal cord compression.
- Collapse or compression of a vertebral body containing metastatic disease (arterial seeding)
- Direct tumour/paraspinal mass extension into vertebral column (10%)
What are the effects of metastatic compression on the spinal cord?
Initially: oedema, vascular congestion + demyelination - reversible
Prolonged compression: vascular injury, cord necrosis + permanent damage
Which cancers have the highest incidence of MSCC?
Breast, prostate + lung
Suggest possible clinical features of MSCC
- prolonged back pain (exacerbated by straight leg raising, coughing, sneezing or straining)
- gait disturbance + limb weakness
- sensory loss + paraesthesia (with well-defined dermatomal level)
- bladder + anal sphincter dysfunction
- diminished performance status/generally unwell
- progressive spasticity (increased tone, clonus and hyperreflexia in limbs below level of MSCC)
A 72 year old man with a Hx of prostate cancer presents with a 3 day Hx of back pain + difficulty walking. Which Ix would you request?
MRI within 24 hrs
A 72 year old man with a Hx of prostate cancer presents with a 3 day Hx of back pain + difficulty walking. MRI shows MSCC at T12. How would you manage him?
- Admit for bed rest with log-rolling
- 16 mg DEXAMETHASONE + PPI
- Radiotherapy (abnormal area + 1-2 vertebrae) or surgery (e.g. balloon kyphoplasty) if patient fit and good prognosis
- analgesia, laxatives etc.
How would you manage someone presenting with malignant SVCO (immediate + ongoing)?
Immediate:
- ensure airway if secure. I + V if required.
- DEXAMTHASONE IV 10mg bolus followed by 4mg every 6hrs
- RT or percutaneous endovascular stenting
Ongoing:
RT or chemo
Suggest different mechanisms through which hypercalcaemia of malignancy can occur.
- PTHrP secretion (80%) e.g. SCC lung, breast: increased bone resorption + renal Ca2+ reabsorption
- osteolytic mets with local cytokine release (20%): increased bone resorption
- tumour secretion of 1,25-dihydroxyvitamin D (lymphoma): increased intestinal Ca2+ absorption
- PTH secretion (parathyroid hormone)
A 54yo woman with known breast cancer presents with constipation, nausea, polydipsia + muscle weakness. Which Ix will you perform?
Bloods
- Ca2+ and corrected Ca2+
- U+Es and creatinine: ?AKI
- PTH + PTHrP
- phosphate: usually decreased
Bedside tests
5. ECG: ?shortened QT interval or arrhythmias
How would you manage someone presenting with hypercalcaemia of malignancy?
Initiate Tx if symptomatic or Ca2+ >3 mmol/L:
- 0.9% NaCl IV: may require several litres at rate of 250-500 ml/hr
+/- FUROSEMIDE if risk of fluid overload - 4mg IVI ZOLENDRONIC ACID: block osteoclastic bone resorption, response generally over 2-4/7
- +/- CALCITONIN: whilst awaiting effects of bisphosphonates
If advanced kidney disease: renal dialysis +/- DENOSUMAB
