PLASMA SOLUBLE INTERLEUKIN-2 RECEPTOR LEVEL IN PATIENTS WITH PRIMARY MYELODYSPLASTIC SYNDROMES - A RELATIONSHIP WITH DISEASE SUBTYPE AND CLINICAL OUTCOME

To assess the hypothesis that the plasma soluble interleukin-2 recepto r (sIL-2R) level may have predictive value for morbidity/mortality in patients with myelodysplastic syndromes (MDS), we determined the plasm a sIL-2R level of 80 MDS patients and examined their subsequent clinic al course. Compared with low-risk MDS (refractory anaemia (RA) and RA with ringed sideroblasts) patients and normal subjects, the plasma sIL -2R level was significantly elevated in high-risk MDS (three other MDS subtypes and acute leukaemia following MDS) patients (high-risk MDS v ersus low-risk MDS, P < 0 . 01; high-risk MDS versus normal subjects, P < 0 . 01). 14/40 low-risk MDS patients developed at least one of the following during the follow-up period: erythrocyte transfusion depend ence, infections requiring hospitalization, disease progression or MDS -related death. The plasma sIL-2R level was higher in these eventful s ubjects than in event-free low-risk subjects (P < 0 . 0001), and all o f 10 low-risk subjects with a plasma sIL-2R level >540 U/ml experience d at least one event. By logistic regression analysis of various param eters in these 40 low-risk subjects, the plasma sIL-2R level was ident ified as the strongest independent parameter for predicting eventful s ubjects (P < 0 . 0047). The plasma sIL-2R level did not show a predict ive value in high-risk MDS. This study revealed that the plasma sIL-2R level is significantly elevated in high-risk MDS and suggested that t he plasma sIL-2R level is a valuable predictive factor for the clinica l outcome in low-risk MDS.