Serum soluble interleukin-2 receptors in epithelial ovarian cancer patients

The levels of soluble interleukin-2 receptors (sIL-R2) were measured in the serum of 52 patients with epithelial ovarian carcinoma as well as in 25 age and sex-matched normal controls. The mean serum level of sIL-R2 was increased in 37 patients (71.2%). Comparison of these levels to those of normal controls showed a highly statistically significant difference (p < 0.001). Serum sIL-R2 levels were not related to histology, clinical stage or the presence of ascites (p = 0.58, p = 0.32 and p = 0.67, respectively), nor did they follow disease activity or response to chemotherapy. However, patients with higher pretreatment sIL-2R levels (more than 1200 U/ml) were found to have a longer survival (p < 0.02), possibly explained by the presence of activated lymphocytes and a better immune surveillance. We conclude that the serum level of sIL-R2: a) is elevated in ovarian cancer patients, b) has no relationship with histological subtypes, tumor burden or the presence of ascites, c) cannot serve as a valuable tumor marker for the monitoring of patient treatment, and d) has a prognostic value for survival.