FRCPath Haem Part 1 EMQs-Oncology 66 and 67

Theme: TLS

Options

Each option may be used once, more than once, or not at all.

A. Oral allopurinol (standard dose)

B. High-dose allopurinol (up to 800 mg/day)

C. Febuxostat

D. Aggressive IV hydration alone

E. Fixed-dose rasburicase (3 mg stat)

F. Weight-based rasburicase (0.2 mg/kg daily)

G. Stop allopurinol and commence rasburicase

H. Continue allopurinol and add rasburicase

I. Emergency hyperkalaemia protocol

J. IV calcium gluconate

K. Withhold calcium replacement

L. Initiate renal replacement therapy

M. Sodium bicarbonate infusion

N. Repeat uric acid with iced sample and interpret cautiously

SCENARIOS

Q1

A 41-year-old man presents with abdominal distension, night sweats, and weight loss. Imaging shows a 14 cm mesenteric mass. Bloods:

• LDH: 6× ULN

• Uric acid: 410 µmol/L

• Creatinine: normal

Biopsy confirms Burkitt lymphoma. He is haemodynamically stable and planned for urgent chemotherapy within 12 hours.

He is drinking poorly due to nausea and has had minimal oral intake for 48 hours.

What is the most appropriate immediate management strategy?

Q2

A 72-year-old frail woman with CKD stage 4 (eGFR 22 mL/min) is diagnosed with DLBCL (bulky 11 cm mass, LDH 3× ULN).

She is started on pre-phase steroids and oral allopurinol.24 hours later:

• Uric acid rises from 380 → 520 µmol/L

• Creatinine increases

• Potassium normal

She remains clinically stable.

What is the best next step?

Q3

A 59-year-old man with CLL is admitted for initiation of venetoclax.Baseline:

• Lymph nodes 9 cm

• LDH 2× ULN

• Uric acid normal

Prophylaxis:

• Oral hydration + allopurinol

12 hours after first dose:

• Uric acid: 600 µmol/L

• Phosphate rising

• Creatinine mildly elevated

He is asymptomatic.

What is the most appropriate escalation?

Q4

A 36-year-old patient with T-ALL (WCC 180 × 10⁹/L) develops 6 hours after starting steroids:

• K⁺ 6.6 mmol/L

• ECG: peaked T waves

• Uric acid: 520 µmol/L

He is drowsy but rousable.

What is the immediate priority in management?

Q5

A 65-year-old man with AML develops confirmed TLS:

• Uric acid: 780 µmol/L

• Creatinine rising

• Phosphate 2.3 mmol/L

He has been on allopurinol for 48 hours.

What is the most appropriate urate-lowering strategy NOW?

Q6

A 54-year-old patient with TLS is receiving rasburicase.Repeat bloods show:

• Uric acid: 90 µmol/L (previously 700)

• Phosphate rising

• Creatinine worsening

The sample was transported routinely (not on ice).

Clinically, the patient is deteriorating.

What is the most appropriate interpretation/action?

Q7

A 68-year-old man with TLS has:

• Calcium: 1.7 mmol/L

• Phosphate: 2.6 mmol/L

• No neuromuscular or cardiac symptoms

The junior doctor is concerned and suggests correction.

What is the most appropriate management?

Q8

A 61-year-old woman with TLS develops:

• Severe muscle cramps

• Carpopedal spasm

• QT prolongation

Biochemistry:

• Calcium 1.65 mmol/L

• Phosphate 2.4 mmol/L

What is the most appropriate immediate treatment?

Q9

A 70-year-old patient with refractory TLS despite hydration and rasburicase has:

• Potassium 6.4 mmol/L (persistent)

• Phosphate rising

• Creatinine doubling

• Oliguria

He is becoming fluid overloaded.

What is the most appropriate next step?

Q10

A 48-year-old man with high-grade lymphoma and TLS is being managed on the ward. A junior doctor proposes:

“We should alkalinise the urine to prevent uric acid crystallisation.”

The patient already has:

• Hyperphosphataemia

• Hypocalcaemia

What is the best response?