Soluble interleukin-2 receptors (sIL-2R) in Hodgkin's disease: outcome and clinical implications

The aim of this study was to assess the prognostic role of soluble interleukin-2 receptors (slL-2R) in Hodgkin's disease (HD) both in the achievement of complete remission (CR) and in predicting disease relapse. Between August 1938 and June 1993 slL-2R serum levels were measured in 174 untreated patients; in 137 of them evaluation was repeated at the end of treatment and in 132 also during the followup. Baseline slL-2R levels (mean +/- standard error) were significantly higher in patients than in 65 healthy control subjects (1842 +/- 129 U ml(-1) vs 420 +/- 10 U ml(-1), P < 0.0001). At the end of treatment 135 out of 137 evaluated patients achieved complete response (CR) and their mean slL-2R serum levels were significantly lower than those at diagnosis (635 +/- 19 U ml(-1) vs 1795 +/- 122 U ml(-1), P = 0.0001). After a median follow-up of 5 years, slL-2R remained low in 114 patients in continuous CR, while they increased in 9 out of 12 patients (75%) who relapsed. However, a temporary increase was also observed in six patients (5%) still in CR. Treatment outcome in terms of freedom from progression was linearly related to sIL-2R levels. Our study confirms that patients with untreated HD have increased baseline levels of slL-2R compared with healthy subjects and that their pretreatment values may be an indication of disease outcome similar to other conventional prognostic factors, such as number of involved sites, presence of B symptoms and extranodal extent.