Changes in laboratory results for cancer patients treated with interleukin-2

The systemic administration of interleukin-2 (IL-2) can lead to significant antitumor responses in some patients with metastatic cancer in whom standard therapy has failed. A limitation of this immunotherapy is the toxicity associated with IL-2 infusion. To assess toxicity, we determined aspartate aminotransferase (AST; EC 2.6.1.1), alanine aminotransferase (ALT; EC 2.6.1.2), gamma-glutamyltransferase (GGT; EC 2.3.2.2), lactate dehydrogenase (LD; EC 1.1.1.27), alkaline phosphatase (ALP; EC 3.1.3.1), creatine kinase (CK; EC 2.7.3.2), total bilirubin (TBI), direct bilirubin (DBI), creatinine, urea nitrogen, and C-reactive protein in serum from 21 patients before and during five consecutive days of IL-2 treatment. Ten patients were followed for an additional five days after the end of IL-2 therapy. The IL-2 infusion caused liver toxicity and prerenal azotemia, as evidenced by significant increases (P <0.05) of all analytes except CK by day 1. There was a progressive increase in the results (except CK) for these tests until IL-2 treatment was stopped. Seven tests related to liver function (AST, ALT, GGT, LD, ALP, DBI, and TBI) showed increases, but the test results indicated significant improvement and moved toward the baseline value five days after the end of IL-2 therapy. Concentrations of creatinine and urea nitrogen in serum were normal three days after the cessation of IL-2 therapy.