tumor lysis syndrome

Full Definition

Tumor lysis syndrome (TLS) is an oncologic emergency that occurs when cancer cells break down rapidly during treatment, releasing their contents into the bloodstream. This leads to dangerous electrolyte imbalances including hyperkalemia, hyperphosphatemia, hypocalcemia, and hyperuricemia, which can cause kidney failure, cardiac arrhythmias, and seizures. TLS is most commonly seen with rapidly proliferating hematologic malignancies and requires immediate intervention with hydration, electrolyte management, and medications to reduce uric acid levels.

Usage

Usage note: Always consider as potential emergency requiring immediate intervention.

In Context

• "The patient developed tumor lysis syndrome within hours of starting chemotherapy." — Emergency department note
• "Prophylactic allopurinol was given to prevent tumor lysis syndrome in this high-risk patient." — Pre-treatment assessment