Interleukin-2-based immunotherapy for the treatment of metastatic renal cell carcinoma: an analysis of 203 consecutively treated patients

Abstract

Purpose: This article analyzes the long-term results of 203 consecutive patients with metastatic renal cell carcinoma who were treated with various recombinant interleukin-2 (rIL-2) -based immunotherapy regimens, and describes factors that may influence response to therapy and long-term survival.

Patients and methods: The response and survival of 203 patients with metastatic renal cell carcinoma treated consecutively between July 1987 and October 1995 at the UCLA Medical Center Kidney Cancer Program with rIL-2-based immunotherapy were analyzed. Patients were divided into four groups: (1) no prior nephrectomy (n = 24), (2) nephrectomy > 6 months prior to rIL-2 therapy (n = 76), (3) nephrectomy < or = 6 months prior to rIL-2 therapy (n = 47), and (4) nephrectomy followed by treatment with rIL-2 and tumor-infiltrating lymphocytes +/- interferon-alpha (n = 56). Response and survival for each of these patient groups and survival per response to therapy were compared.

Results: The overall median survival for all patients was 18 months, and survival at 1, 2, and 3 years after therapy was 61%, 40%, and 31% percent, respectively. A total of 12 patients (6%) achieved a complete response, and all were alive at 3 years. Of 36 patients (18%) who achieved a partial response and 41 patients (20%) with stable disease, 3-year survival was 37% and 50%, respectively. The survival of patients with a partial response or stable disease was significantly better than that of patients who exhibited progressive disease. Patients with nephrectomy > 6 months prior to rIL-2 therapy had a 46% 3-year survival rate, compared with a 9% 3-year survival rate for patients with nephrectomy < or = 6 months prior to rIL-2 therapy and a 4% 3-year survival rate for patients with no nephrectomy. Patients treated with tumor-infiltrating lymphocytes had a 38% 3-year survival rate, which was also significantly better than patients treated with nephrectomy < or = 6 months prior to rIL-2 therapy or with no nephrectomy.

Conclusion: This analysis demonstrated that rIL-2-based therapy offers a significant survival benefit to patients with advanced metastatic renal cell carcinoma, compared with historical controls. Furthermore, we have shown that nephrectomy > 6 months prior to rIL-2 therapy and nephrectomy followed by treatment with tumor-infiltrating lymphocytes/rIL-2 +/- interferon-alpha was associated with the greatest survival benefit. Tumor response to rIL-2-based therapy and time from nephrectomy to treatment were the most important predictors of survival. Randomized studies in a large group of patients are needed to confirm these observations.