Y5 - Tumour Lysis Syndrome

Question 1

def

Answer 1

combination of metabolic and electrolyte abnormalities (due to cell lysis) which occurs in patients with cancer following chemotherapy

Question 2

what occurs as a result of excessive cell lysis

Answer 2

in high quantities in the cell:
hyperuricaemia
hyperphosphataemia
hyperkalaemia
in low quantities in the cell:
hypocalcaemia

Question 3

what condition is TLS most associated with

Answer 3

burkitts lymphoma (NHL)

Question 4

what malignancies is TLS common in

Answer 4

malignancies with high proliferating rates such as burkitts lymphoma

Question 5

what are the three conditions most associated with TLS

Answer 5

NHL (burkitts)
ALL
AML

Question 6

why are elderly people more likely to get TLS

Answer 6

reduced GFR so metabolic and electrolyte abnormalities are less easily corrected

Question 7

aetiology

Answer 7

appears in haematological malignancies with high proliferating rates such as NHL (burkitts), ALL, AML

reduced GFR is most likely to increase likelihood of TLS
additionally high LDH and WCC indicate a high tumour load and increased risk of TLS

Question 8

risk factors

Answer 8

haematological malignancy
chemotherapy
renal failure

Question 9

what indicates a high tumour burden

Answer 9

high levels of LDH, WCC, uric acid

Question 10

what are features of TLS

Answer 10

Hx of haematological malignancy and chemotherapy, renal failure

N+V+D
muscle weakness and cramping
paraesthesia

Question 11

why might cardiac arrythmias occur

Answer 11

due to hyperkalaemia or hypocalcaemia

Question 12

why might seizures occur

Answer 12

severe hypocalcaemia or hyperphosphataemia

Question 13

what is the first line investigation for TLS

Answer 13

bloods biochemistry for (uric acid, phosphate, potassium, calcium)

Question 14

what is the gold standard for diagnosis of TLS

Answer 14

bloods biochemistry

Question 15

what signs may be present with hypocalcaemia

Answer 15

chvosteks sign

trousseaus sign

Question 16

what is chvosteks sign

Answer 16

face is tapped and causes twitching of nose or lips

Question 17

what is trousseaus sign

Answer 17

when a BP cuff is inflated in occludes the brachial artery and causes the wrist to flex and fingers to extend

Question 18

investigations

Answer 18

1 bloods biochemistry

• high PUP (phosphate, uric acid, potassium)
• low calcium
• high WCC

Question 19

why is pH low in TLS

Answer 19

uric acid

Question 20

what is the most important feature of management of TLS

Answer 20

prevention

Question 21

what should be done if TLS develops despite prevention

Answer 21

correction of laboratory and clinical abnormalities

Question 22

how are patients stratified into risk of developing TLS

Answer 22

low risk
intermediate risk
high risk

Question 23

which patients are at low risk of developing TLS

Answer 23

• asymptomatic non-hodgkins lymphoma

- low proliferating malignancies

Question 24

how are low risk patients managed

Answer 24

regular monitoring of blood biochemistry and fluid balance

Question 25

which patients are at intermediate risk of developing TLS

Answer 25

- diffuse large B cell lymphoma - ALL (WBC 50-100) - AML (WBC 10-50) - CLL (WBC 10-100) - CML - MM - solid tumours with rapid response to therapy

Question 26

how are intermediate risk patients managed

Answer 26

2 days prior to cytotoxic therapy patients should receive IV hydration with isotonic NaCl to maintain urinary output of 100mL/hr -improves intravascalar volume -enhances renal blood flow -improves GFR and reduces uric acid, phosphate, and potassium in the blood give loop diuretics if urine output still unsatisfactory

Question 27

why may allopurinol be given

Answer 27

it is a xanthine oxidase inhibitor which prevents the degradation of purine to uric acid

Question 28

which patients are at high risk of developing TLS

Answer 28

highly proliferative malignancies - burkitts lymphoma - lymphoblastic leukaemia - ALL (WBC>100) - AML (WBC>50)

Question 29

how are high risk patients managed

Answer 29

same as intermediate e.g. IV hydration | however give rasburicase instead of allopurinol

Question 30

why is rasburicase used in high risk patients instead of allopurinol

Answer 30

rasbicuricase transforms uric acid into allantoin which is far more soluble than uric acid and so is removed by the kidney

Question 31

management for low risk patients

Answer 31

regular monitoring and assessment

Question 32

management for intermediate risk patients

Answer 32

prechemotherapy IV hydration regular monitoring and assessment allopurinol

Question 33

management for high risk patients

Answer 33

prechemotherapy IV hydration regular monitoring and assessment rasburicase

Question 34

which patients also need an phosphate binder

Answer 34

ALL patients

Question 35

complications

Answer 35

acute renal failure cardiac arrythmias seizures

Question 36

prognosis

Answer 36

rasburicase reduces dialysis required in acute renal failure | majority of complications can be managed successfully