Tumor Lysis Syndrome

Who is at Risk?


If killing cancer cells is the goal of therapy, then it may seem odd at first to hear about the risk of the treatment of a rapidly growing blood cancer that responds really well to chemotherapy.

But in tumor lysis syndrome, it’s not the risk of the cancer coming back that doctors are referring to -- it’s the risk that the body won’t be able to handle the heavy load from all of the disintegrating (lysed) cancer cells.

What is Tumor Lysis Syndrome?

So, what is TLS and why is it an emergency? Well, with treatment, the cancer cells disintegrate all at once, or lyse, dumping into the bloodstream all of the cell contents--including potassium, phosphate, and the cell’s DNA and RNA, or nucleic acids, which get broken down further into uric acid. The kidneys can only process so much, and when they are overwhelmed, bad things happen. The blood chemistry becomes out of balance, which can lead to cardiac arrest, and kidney damage can also occur.

Doctors and patients are grateful when a cancer responds well to chemotherapy, but this can also present its own set of challenges. Your doctor will assess your risk of treatment-related TLS in advance, and take any necessary precautions.

In the treatment of blood cancers, TLS occurs most often when cytotoxic therapy is given to patients with high-grade lymphomas or acute lymphoblastic leukemia.

But it can also occur spontaneously in patients with other types of cancer, and in these cases it’s not associated with treatment.

Not all patients have the same level of risk, and not all malignancies are associated with an increased risk for TLS. The most important treatment is actually anticipating that TLS could happen and exercising prevention.

What are some Risk Factors for TLS?

Certain blood cancers are linked to an increased risk of TLS. These include non-Hodgkin's lymphoma—especially Burkitt lymphoma, lymphoblastic lymphoma, ALL, and AML.

Other risk factors for TLS include:

  • Large tumor burden
  • Tumors with high growth rate
  • Cancers that are very responsive to chemotherapy
  • Acute lymphocytic leukemia and acute myeloid leukemia with high WBC counts
  • Certain substances detected in the bloodstream
    • Elevated LDH
    • Elevated uric acid
  • Preexisting kidney impairment
  • Dehydration
  • Acute kidney failure developing after treatment

How Do Doctors Prevent TLS?

Since prevention is the best treatment, doctors try to determine the individual patient’s risk for TLS and then act accordingly. Prevention includes IV hydration, which can help the kidneys eliminate some of the undesirable substances that are released from the dying cancer cells. These substances include potassium, phosphate, and the cell’s DNA and RNA, or nucleic acids, which get broken down further into uric acid.

For patients at high risk of TLS, drugs like allopurinol or rasburicase may be used to try to keep uric acid levels in a safe range.

In addition to aggressive hydration and correcting abnormalities, monitoring plays an important role for patients who are at risk for TLS. Doctors keep track of how much urine a patient is making and follow electrolytes and serum uric acid levels carefully.


Wilson FP, Berns JS. Tumor lysis syndrome: new challenges and recent advances. Advances in Chronic Kidney Disease. 2014;21(1):18-26.

Sarno J. Prevention and management of tumor lysis syndrome in adults with malignancy. Journal of the Advanced Practitioner in Oncology. 2013;4(2):101-106.

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