Tumor lysis syndrome is a life-threatening complication in cancers where rapid cell loss is caused when treatment is initiated.
In tumor lysis syndrome, there is a rapid decrease of cells in a matter of hours/days causing depletion of intracellular substances into extracellular space. This causes an increased serum concentration of calcium, phosphate, magnesium, urine substances, and uric acid.
Uric acid can lead to precipitation of uric acid crystals in the renal tubules and lead to reduction of renal function. Renal failure is worsened by the binding of phosphate ions with calcium ions creating calcium phosphate crystals which also precipitate in the tubules. When calcium phosphate is > 8-10 mmol/l, the risk of precipitation of crystals in the kidneys and other tissue, increases.
Hyperkalemia from release of intracellular potassium is the greatest acute threat to the patient. Levels > 7 mmol/l increases the risk for cardiac arrhythmia and cardiac arrest.
Tumor lysis syndrome is observed in association with the first course of chemotherapy, start of radiation therapy, or steroid treatment.
Patients who are disposed for developing tymor lysis syndrome have:
- a relatively large tumor mass with high cell proliferation
- elevated leukocyte count (leukemized blood profile)
- elevated LDH
- elevated uric acid
- reduced renal function
The patient`s well being is often already influenced by the disease. Therefore, the degree of electrolyte disturbance contributes to complicating the patient's progress.
The prognosis is good with adequate prophylaxis and timely treatment.
- Acute leukemia, lymphoblastic lymphoma, Burkitt's lymphoma (often observed)
- Other aggressive B- and T-cell lymphomas and indolent lymphomas with massive leukemization treated with monoclonal antibodies (less frequent)
- Solid tumors such as small cell lung cancer, medulloblastoma, testical cancer, and advanced breast cancer (rare)
- Prevention of tumor lysis syndrome