Serum-soluble interleukin-2 receptor (sIL-2R) level determines clinical outcome in patients with aggressive non-Hodgkin's lymphoma: in combination with the International Prognostic Index

Purpose: The aim of the present study was to assess the prognostic significance of serum soluble interleukin-2 receptor (sIL-2R) in aggressive non-Hodgkin's lymphoma (NHL). Methods: One hundred and thirteen consecutive patients with previously untreated aggressive NHL (diffuse large B-cell lymphoma, 96; peripheral T-cell lymphoma, 17) prospectively participated in this study between 1995 and 2001. The patients were treated with 6-8 cycles of a CHOP or THP (pirarubicin)-COP regimen. Results: A high serum sIL-2R level (2,000 U/ml and over) at onset was associated with a low complete remission rate. Patients with high sIL-2R had significantly lower survival rates (5-year, 24%) than those with low sIL-2R (under 2,000 U/ml) (74%) (P < 0.01). Multivariate analysis employing sIL-2R levels and conventional prognostic factors demonstrated that high sIL-2R, presence of B-symptoms, and advanced age (60 years and older) were significantly unfavorable variables for overall survival. In addition, we attempted to use sIL-2R in combination with the International Prognostic Index (IPI). The patients in the high (H) risk group and those with high sIL-2R in the low-intermediate (LI)/high-intermediate (HI) risk group had significantly lower survival rates than the patients in the low (L) risk group and those with low sIL-2R in the LI/HI risk group (P < 0.001). Conclusion: The results suggest that a high serum sIL-2R level predicts a poor prognosis in aggressive NHL and may be a useful biomarker for selecting appropriate treatment when used in combination with the IPI.