Advanced Oncology Certified Nurse Practitioner (AOCNP) Certification Practice Test

Which laboratory findings are indicative of tumor lysis syndrome (TLS)?

1. Hypokalemia and hypocalcemia

2. Hyperkalemia and hyperphosphatemia

3. Normocalcemia and hyperuricemia

4. Dehydration and anion gap metabolic acidosis

The correct answer is: Hyperkalemia and hyperphosphatemia

The laboratory findings indicative of tumor lysis syndrome (TLS) include hyperkalemia and hyperphosphatemia. TLS occurs when large quantities of tumor cells die in a short period, causing the contents of the cells to be released into the bloodstream. This rapid release can lead to several metabolic imbalances. Hyperkalemia is a critical finding in TLS because the breakdown of cells releases potassium into the circulation, which can lead to potentially dangerous cardiac arrhythmias. Similarly, hyperphosphatemia occurs due to the release of phosphate from lysed tumor cells, which can result in acute secondary complications such as acute kidney injury if the phosphate binds with calcium, causing hypocalcemia in severe cases. While other options present various metabolic conditions, they do not accurately reflect the biochemical profile commonly seen in TLS. Understanding these specific changes is crucial for nurses and healthcare professionals to identify and manage TLS effectively, preventing serious complications in patients undergoing treatment for malignancies.