A 50-year-old patient with aggressive non-Hodgkin lymphoma receives their first dose of chemotherapy. Within 24 hours, labs show hyperkalemia, hyperphosphatemia, hypocalcemia, and hyperuricemia. What is the most important initial management step for this condition?

✓ Correct Answer: Option C

This patient has tumor lysis syndrome. The cornerstone of management is aggressive intravenous hydration to prevent kidney injury, along with allopurinol or rasburicase to reduce uric acid levels. While individual electrolyte abnormalities are managed, these are the key initial steps.