Hyperkalemia complicating splenic irradiation of chronic lymphocytic leukemia

Hyperkalemia is an infrequent complication of the therapy of malignant disease. In previously reported cases, hyperkalemia following the institution of chemotherapy has been associated with acute renal failure. In this report, we present a patient with chronic lymphocytic leukemia who developed hyperkalemia following splenic irradiation. Necrosis of tumor cells, either as direct or an abscopal effect appears to be implicated as a cause of hyperkalemia. It seems appropriate to monitor potassium levels when therapy of a responsive tumor is instituted.