[Serum soluble interleukin-2 receptor levels in patients with renal cell carcinoma: a comparison of values before and after surgery].

This study was carried out in order to find out whether soluble interleukin II receptor (sIL-2R) levels were useful as a treatment biomarker in patients with renal cell carcinoma (RCC). The subjects consisted of 17 patients with RCC who had been scheduled for radical or partial nephrectomy. Serum levels of sIL-2R were measured before surgery and 1 and 3 months after surgery. We also analyzed the relationship of preoperative sIL-2R to pathologic TNM-stage, grading and presumptive tumor volume. The mean value of pre-operative sIL-2R in patients with RCC was 496.5 U/ml as compared with 302.7 U/ml in the control group (p = 0.056). Pre-operative sIL-2R values were 411.1 U/ml in stage I (n = 6), 481.4 U/ml in stage III (n = 11) and 1,330 U/ml in stage IV (n = 1). There was no significant difference between stage I and stage III. As compared with pathologic grading, pre-operative sIL-2R levels in patients with grade 2 were significantly higher than those with grade 1 (609.8 U/ml versus 288.7 U/ml, p = 0.016). There existed a significant correlation between preoperative sIL-2R and presumptive tumor volume (r = 0.61, p = 0.008). Three months after surgery, sIL-2R values were significantly higher than before surgery. Serum sIL-2R levels seemed to bear some relationship to the extent of disease in patients with RCC. Values of sIL-2R were significantly higher after than before surgery at least for a three-month postoperative period, suggesting a response to trauma of surgery. Further long term studies were required to clarify if sIL-2R could predict the progression of disease.