Oncologic Emergencies: TLS

Question 1

TLS definition

Answer 1

Large number of cancer cells dies within a short period and cell contents are released into the blood

Question 2

Electrolyte disturbances in TLS

Answer 2

Hyperkalemia
Hyperphosphatemia
Hypocalcemia
Hyperuricemia

Question 3

Lab TLS

Answer 3

≥2 electrolyte abnormalities within 3 days before or 7 days after treatment initiation

Question 4

Hyperkalemia definition

Answer 4

≥6.0 mEq/L

ECG abnormalities, cardiac arrest, fatigue

Question 5

Hyperuricemia definition

Answer 5

≥8.0 mEq/L

AKI, crystal neuropathy

Question 6

Hyperphosphatemia definition

Answer 6

≥4.5 mEq/L

AKI, GI upset, AMS

Question 7

Hypocalcemia definition

Answer 7

≤7.0 mg/dl

AMS, seizures, arrhythmias, tetany, spasms

Question 8

Clinical TLS definition

Answer 8

Presence of lab TLS plus AKI, seizures or neuromuscular irritability, cardiac arrhythmia

Question 9

Cancer-related TLS risk factors

Answer 9

high proliferation rate, tumor bulk, circulating tumor cells, sensitivity to cytotoxic therapy

Question 10

Patient-specific TLS risk factors

Answer 10

elevated baseline uric acid, nephropathy, hydration status, hypotension, acidic urine, LV dysfunction/HF

Question 11

TLS prevention

Answer 11

Hold causative agents: diuretics, calcium/potassium/phosphate-containing supplements and nutritional products, ACEis, nephrotoxic agents

Hydration: IV NS, avoid adding bicarb

Risk-based prevention: based on low, intermediate, high risk

Question 12

Low risk for TLS

Answer 12

Observation, normal hydration, monitoring

Question 13

Intermediate risk for TLS

Answer 13

Hydration, allopurinol, consider rasburicase

Question 14

High risk for TLS

Answer 14

Hydration, rasburicase, allopurinol

(Dialysis if refractory to rasburicase)

Question 15

Indications for dialysis

Answer 15

refractory volume overload, oliguria, or anuria; persistent hyperkalemia or hyperuricemia, hyperphosphatemia-induced symptomatic hypocalcemia

Question 16

Hyperkalemia treatment

Answer 16

Hydration, use diuretics to optimize urine output

Calcium chloride 1g IV
Regular insulin 10 units PLUS IV dextrose 25g
Sodium bicarb 50 mEq IV
SPS 15-60g PO
Hemodialysis or CRRT

Question 17

Hyperphosphatemia treatment

Answer 17

First-line is IV hydration
Restrict dietary intake to 800-1000mg/day
Phosphate binders
Last-line: dialysis

Question 18

Phosphate binders

Answer 18

Calcium acetate
Calcium carbonate
Aluminum hydroxide
Lanthanum
Sevelamer

Question 19

Hypocalcemia treatment

Answer 19

Typically resolves with Hyperphosphatemia treatment, only treat symptomatic hypocalcemia to avoid overcorrection (cardiac arrhythmias, seizures, tetany)

Question 20

Indication for allopurinol in TLS

Answer 20

Patients at risk for developing TLS
Initiate 24hrs prior to chemo

Question 21

Allopurinol cautions

Answer 21

Drug interactions, severe hypersensitivity

Question 22

Rasburicase indication in TLS

Answer 22

Suitable for patients with preexisting hyperuricemia before treatment, those at high risk for TLS, or patients with spontaneous TLS

Question 23

Rasburicase cautions

Answer 23

G6PD deficiency
Cost (super expensive)