Recombinant leukocyte interferon alpha-2a and medroxyprogesterone in advanced renal cell carcinoma. A randomized trial

The treatment of metastatic renal cell carcinoma by continuous intravenous infusion of recombinant interleukin-2

Between March 1989 and June 1990, 133 patients were treated with interleukin 2 (rIL-2) for metastatic renal cell carcinoma (RCC) in a multicentre open non-randomised study. The results show an objective response rate of 14% (95% confidence interval 8-21) with 4 patients achieving a complete remission. This is in keeping with the data from previous studies using rIL-2 by continuous infusion. It is of interest that 87% of objective responses occurred in hospitals that entered 5 or more patients.

The impact of interleukin-2 on survival in renal cancer: a multivariate analysis

The purpose of this analysis was to compare the survival of patients with advanced renal carcinoma treated with intravenous recombinant interleukin-2 to the survival of matched patients taken from the large and well characterised database of the Eastern Cooperative Oncology Group (ECOG). Recombinant interleukin-2 (rIL-2) given by continuous intravenous infusion was used to treat 387 patients with advanced adenocarcinoma of the kidney in five multi-centre studies and 327 of these patients fulfilled the study eligibility criteria and were evaluable for response, toxicity and survival. The survival of patients treated with rIL-2 was compared in a multi-variate survival analysis taking account of all identified prognostic factors to 390 control patients receiving chemotherapy derived from the database. Thirteen patients treated with rIL-2 achieved a complete remission of their disease and 32 a partial remission giving an overall response rate of 14%. Remissions were durable with a median duration of 357 days for partial remissions and a median duration in excess of 926 days for complete remissions. Most patients experienced fever or mild to moderate hypotension and other toxicities are described. However, only 11 patients required admission to intensive care and in only five cases was this judged to be due to treatment toxicity. There were three deaths judged to be probably due to treatment toxicity. rIL-2 treatment was associated with significantly prolonged survival compared to the ECOG control patients. Patients with good prognostic features appeared to have a greater survival benefit from rIL-2 than those with poor prognostic features. This analysis provides the first evidence that rIL-2 prolongs survival in patients with advanced renal cancer but cannot provide proof which should be sought in randomised prospective trials drawing on the hypotheses generated herein.

Treatment of gastrointestinal and renal adenocarcinomas with interferon-alpha

Treatment of adenocarcinomas with interferon-alpha as a single agent has been disappointing. Recent efforts have focused on the combination of interferon with cytotoxic drugs such as 5-fluorouracil. A number of postulated mechanisms can explain synergistic interactions between 5-fluorouracil and interferon-alpha, including interaction with pyrimidine pathways, and alteration of drug metabolism. Previous studies in colorectal cancer, using 5-fluorouracil and interferon-alpha are reviewed, suggesting that the combination is more active than 5-fluorouracil alone. In renal cell carcinoma, the literature is reviewed, suggesting that daily interferon is the most efficacious schedule; preliminary data suggest that addition of 5-fluorouracil to interferon-alpha can double the expected response rate of 16% achieved by interferon-alpha alone.