Tumor lysis

syndrome

(TLS)

Done by:

Salah Saleh

TLS is an oncology emergency occures when cancer

cells start to break down and die.

While blood cells die they release intracellular

components into the bloodstream, leading to extra

amount of unuseful elements in the body which the

kidneys can not remove the wastes from the body.

Definition

The signs and symptoms of TLS may occur as early

as a few hours after the start of chemotherapy, but

are more common 24 to 48 hours after treatment

begins.

The mortality rate for patients who develop TLS is

about 18%

TLS is a group of abnormal changes in the blood

which are:

1. Potassium (Hyperkalemia)

2. Uric acid (Hyperuricemia)

3. Phosphate (Hyperphosphatemia)

4. Calcium (Hypocalcemia)

HYPERKALEMIA:

* Hyperkalemia is defined as serum K level > 6.0 mEq/L or 25%

increase from baseline

* Causes cardiac arrhythmia

* It is usually seen 6 -72 hours post-chemotherapy

* Neuromuscular and cardiac tissues are most susceptible to

changes in K level

* Neuromuscular symptoms may include: Fatigue, muscle

cramps, anorexia, paresthesias, and irritability

* In the cardiac tissue a variety of electrocardiographic changes

can occur, including peaked T wave (>5 mm)

Hyperuricemia:

* Hyperuricemia is defined as serum uric acid >8.0

mg/d or 25% increase from baseline 3 days before or

7 days after the initiation of chemotherapy

* Usually develops 48 to 72 hours after therapy

* Excretion is through the proximal renal tubule

Allopurinol:

* Inhibits the conversion of hypoxanthine to xanthine and of xanthine to uric acid by inhibiting xanthine oxidase

* Optimally, it’s initiated one to two days before starting chemotherapy

Rasburicase: * Administered intravenously, rasburicase converts uric

acid to Allantoin, which is much more soluble in urine than uric acid

* The drug works quickly (in four hours) to

reduce uric acid levels

Hyperphosphatemia:

Is defined as serum phosphate > 4.5 mg/dL

Hypocalcemia:

is defined as serum calcium level < 7.0 mg/dL How it is happened?

The kidneys try to eliminate the excess phosphorus

As serum phosphate levels increase, phosphate ions (which are

negatively charged) combine with calcium ions (positively

charged), resulting in decreased serum calcium levels

(hypocalcemia).

These calciumphosphate complexes precipitate in soft tissues and

the renal tubules, causing tubular obstruction and acute renal

failure

PREVENTION:

HYDRATION:

* Patients receiving nephrotoxic chemotherapy such as cisplatin should be well hydrated

* IV fluid generally is administered 48 hours prior to chemotherapy

* Hydration also improves the rate of renal blood flow

MEDICATIONS:

The intake of nephrotoxic agents and other medications that may

exacerbate the kidney failure should be discontinued

Examples of nephrotoxic drugs:

1. antimicrobials such as aminoglycosides, amphotericin B

2. nonsteroidal anti-inflammatory drugs

3. Other medications such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers… etc

Patients at high risk for tumor lysis syndrome should have the following levels monitored at least three times daily:

* Blood urea nitrogen (BUN)

* Creatinine

* Uric acid

* Potassium

* Calcium

* Phosphate

* Lactate dehydrogenase (LDH)

Management:

* Identify patients at High-risk:

Burkitt lymphoma, lymphoblastic lymphoma, or B-

cell acute lymphoblastic leukemia

Several chemotherapy agents are associated with TLS

as well including:

cytarabine, cisplatin, etoposide and paclitaxel

Cont

* Hydration and effective urine flow rates remain a

cornerstone of TLS prevention and treatment

* Administration of hypouricemic drugs

* Restriction of dietary phosphorus

* The aim in the management of TLS is to correct

abnormalities in the blood components and to

manage renal failure

Case study

A 45-years-old patient presented with Burkitt

lymphoma with a history of hypertension and

mild renal insufficiency, he is starting treatment

with Hyper-CVAD Regimen.

Based on this clinical situation, what is the patient’s

risk for developing tumor lysis syndrome?

1. High risk

2. Intermediate risk

3. Low risk

4. No risk

1. High risk

2. Intermediate risk

3. Low risk

4. No risk

Which of the following laboratory values are

important in developing a plan for monitoring and

treating TLS?

1. WBC, Lactate dehydrogenase (LDH), serum

potassium, Calcium, Creatinine, Phosphorus, Uric

acid

2. RBCs, albumin, alkaline, total bilirubin

3. CBC, CO2, bicarbonate, serum magnesium

1. WBC, Lactate dehydrogenase (LDH),

serum potassium, Calcium, Phosphorus,

Creatinine, Uric acid

2. RBCs, albumin, alkaline, total bilirubin

3. CBC, CO2, bicarbonate, serum magnesium

Thank you for your attention

References:

• http://www.cancer.ca/en/cancer-information/diagnosis-and-treatment/managing-side-effects/tumour-lysis-syndrome/?region=on

• http://emedicine.medscape.com/article/282171-treatment#d10

• http://journals.lww.com/oncology-times/pages/articleviewer.aspx?year=2010&issue=04251&article=00002&type=Fulltext

• https://www.researchgate.net/publication/6306831_Tumor_Lysis_Syndrome