DETECTION OF SOLUBLE INTERLEUKIN-2 RECEPTOR AND INTERLEUKIN-10 IN THE SERUM OF PATIENTS WITH AGGRESSIVE NON-HODGKINS-LYMPHOMA - IDENTIFICATION OF A SUBSET AT HIGH-RISK OF TREATMENT FAILURE

Background. This study explores the ability of the combined detection of soluble IL-2 receptor (sIL-2r) and interleukin-10 (IL-10) to predict treatment failure in patients with aggressive non-Hodgkin's lymphoma (NHL) and to evaluate the modifications in cytokine measurements induced by the therapeutic administration of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). Methods. Serum levels of sIL-2r and IL-10 were measured serially in 93 patients with newly diagnosed aggressive NHL treated with four courses of a multiagent chemotherapy regimen. GM-CSF was administered subcutaneously in 39 of these patients from day +5 to day +18 after each chemotherapy course. Results. Pretreatment levels of sIL-2r were greatly elevated in patients with NHL compared with control subjects (P < 0.001), significantly correlating with the Ann Arbor stage (P < 0.001) and beta(2)-microglobulin (beta(2)-m) concentrations (r = 0.552, P = 0.004). IL-10 was detected in 37 patients at diagnosis, with no correlation with clinico-hematologic parameters, and was not detected in the control sample (P < 0.001). Cytokine and receptor levels progressively declined to normal ranges in responding patients, whereas they remained elevated in nonresponders. During administration of GM-CSF, the authors observed an increase of sIL-2r, whereas lower elevations were recorded for IL-10. However, on completion of the induction treatment, cytokine/receptor levels were comparable in patients with the same type of response, whether or not they had received GM-CSF. In the five patients who were investigated at relapse, the levels of sIL-2r, beta(2)-m, and lactic dehydrogenase were found to be elevated. IL-10 concentrations were high in three of these patients: two already had detectable levels at presentation, whereas one tested positive only on recurrence. No single parameter was associated with response to therapy, but the combination of elevated IL-10 and sIL-2r concentrations greater than 3000 U/ml resulted in a subset of eight patients who failed induction chemotherapy (P < 0.001). In addition, six of eight patients with high IL-10 and beta(2)-m concentrations greater than 3.3 mg/l had an unfavorable outcome (P = 0.003). A multivariate regression model was used to identify sIL-2r (P = 0.004) and beta(2)-m (P = 0.043) as the covariates that amplified the prognostic ability of IL-10. Conclusions. sIL-2r and IL-10 measurements provide valuable information for better management of patients with NHL as markers to monitor disease activity and as prognostic indicators.