Peripheral blood neutrophils as independent immunologic predictor of response and long-term survival upon immunotherapy in metastatic renal-cell carcinoma.

The aim of this study was to evaluate the prognostic impact of pretreatment neutrophils, previously rendered statistically independent, on the response and on long-term survival of metastatic renal carcinoma patients treated with outpatient subcutaneous (s.c.) interleukin-2 (IL-2) and s.c. interferon (IFN)-alpha. We assessed a total of 495 patients receiving s.c. IL-2/s.c. IFN-alpha-based therapy. While 417 patients with neutrophil counts <6500 cells/microL at baseline achieved 30% objective responses and a median survival of 22 months, 78 patients with pretreatment neutrophil counts >or= 6500 cells/microL had 18% objective responses and a median survival of 9 months (p=0.0000). In conclusion, pretreatment peripheral blood neutrophils <6500/microL constitute an immunologic predictor of tumor response and long-term survival in metastatic renal-cell carcinoma patients treated with s.c. IL-2 and s.c. IFN-alpha-based regimens.