Tumor Lysis Syndrome
What is Tumor Lysis Syndrome (TLS)?
Tumor lysis syndrome (TLS) is an oncologic emergency where cells in the body break down too quickly. This breakdown causes chemicals and electrolytes in the body to get out of balance. TLS can be caused by the treatment, or lack of treatment, of cancer.
During the treatment of cancer, cells are killed and broken down by chemotherapy or radiation. The body is not always able to process the quick breakdown of these cells and the release of the cell’s contents. The result is an imbalance of electrolytes:
- Hyperuricemia – High level of uric acid. Uric acid is a chemical created when the body breaks down purine. Purine is found in food and drinks such as liver, anchovies, dried beans and beer. Uric acid is dissolved in the blood, travels to the kidneys, and then leaves the body through urine. You may have no signs or symptoms of hyperuricemia. However, symptoms may include gout (inflammation of a joint) and kidney stones.
- Hyperkalemia – High level of potassium. Potassium is needed for cells to work normally which enables nerves and muscles to communicate. Most people get all the potassium their body needs through eating foods such as bananas, oranges, and green leafy vegetables. Potassium leaves the body through urine. You may have no symptoms, but possible symptoms are muscle weakness, chest pain, and heart palpitations.
- Hyperphosphatemia – High level of phosphate. Phosphate makes energy in the body. It also helps muscle and nerves work, helps with bone growth, and maintains the acid-base balance in the body. It enters your body through food. It leaves the body through urine. There are no symptoms of hyperphosphatemia.
- Hypocalcemia – Low level of calcium. Calcium is a mineral that is used for cell signaling, muscle function, nerve function and heart function. It also is needed for blood clotting, bone maintenance and formation. Calcium leaves the body through the kidneys. Signs and symptoms of hypocalcemia are muscle twitching, numbness and tingling of fingers and toes, and confusion.
When the minerals and electrolytes leave the dying cells too quickly, your body cannot keep up. TLS can cause renal failure, seizures, cardiac dysrhythmias, and if not quickly managed, death.
How is TLS treated?
Patients at high risk for TLS will receive treatment to try to prevent TLS. They will be closely monitored during treatment, including frequent blood tests and measuring of urine output. Patients at high risk are those with a large tumor volume. Large tumor volume happens mostly with lymphomas or leukemias when white blood cell counts are high. If a patient is at high risk, their chemotherapy will be given in the hospital so they can be closely monitored. To prevent TLS a patient may receive:
- Intravenous Hydration – The administration of fluid through an IV. The goal of IV hydration is to improve renal perfusion (the movement of fluid through the kidneys). The more a patient urinates, the less uric acid and calcium phosphate can build up in the kidneys. However, you don’t want to give a patient so much fluid that their kidneys cannot handle it. The fluid then builds up in the body causing edema (swelling) and in extreme cases heart failure.
- Hypouricemic Medication – These medications cause your body to make less uric acid, which then prevents hyperuricemia. Allopurinol and Rasburicase are the two most commonly used medications.
Even with these steps to prevent it, some patients still develop TLS. Treatment of TLS includes: heart and lab value monitoring, treating electrolyte changes with medications, allopurinol or rasburicase, and kidney dialysis if needed. Dialysis is a treatment where blood is filtered through a machine and returned to the body, performing the filtering action of the kidneys.
Despite preventative measures, some patients still develop TLS. Management of TLS includes: cardiac and lab value monitoring, treating specific electrolyte abnormalities with medications to either lower or increase the value, rasburicase and kidney dialysis if needed. Dialysis is a treatment in which blood is filtered through a machine and returned to the body, performing the filtering action of the kidneys.
When to contact your care team
If you are having signs and symptoms of hyperuricemia, hyperkalemia, hyperphosphatemia or hypocalcemia as described above, you must contact your care provider right away.