The role of adjuvant immunotherapy after radical nephrectomy and prognostic factors in pT3N0M0 renal cell carcinoma

Abstract

Five-year overall survival after radical nephrectomy in pT3N0M0 renal cell carcinoma is 35-50%. In light of immunotherapy, which has shown some activity in advanced diseases with increasing efficacy in limited metastatic invasion, we decided to explore the theoretical advantage of adjuvant immunotherapy in radically resected stage pT3N0M0 renal cell carcinoma. We studied several factors including tumor size, nuclear grade, mean nuclear area and expression of p53 protein to find out which factor is concerned with disease progression. A total of 10 patients with pT3N0M0 RCC who received radical nephrectomy from February 1992 to April 1999 were randomly assigned to receive treatment with either interferon-alpha alone or interferon-alpha plus vinblastine. Eight patients with pT3N0M0 RCC who received only radical nephrectomy from January 1984 to February 1993 were analyzed and the results were compared with the first group. Six out of 10 (60%) patients in the adjuvant immunotherapy group are alive with no evidence of disease. Metastases were documented in 4 patients (40%) with a median interval to progression of 17.5 months. All of them died of tumor. In the surgery only group, 5 out of 8 patients (62.5%) are still alive with no evidence of disease. Two patients (25%) developed distant metastases and both of them died of tumor. The median progression interval was 11 months. There were no statistical differences in time to progression and survival rate between the two groups. In the univariate analysis using a log-rank test, the expression of p53 protein seemed to be associated with shorter survival (p = 0.0591). However, in the multivariate analysis using Cox's proportional hazard model, no parameter had significant independent prognostic value. We concluded that adjuvant immunotherapy did not improve the survival of patients with pT3N0M0 RCC. Furthermore, we failed to find significant prognostic factors in patients with pT3N0M0 RCC.