A series of 474 patients with renal cell carcinoma (RCC), who had radical nephrectomy during a period of 15 years, was studied to assess the prognostic significance of various pathologic parameters (tumor stage [pT], lymph node status, metastasis, tumor grade, venous involvement) and value of preoperative embolization of renal artery. There were: 20 (4%) pT1, 204 (43%) pT2, 245 (52%) pT3, and 5 (1%) pT4 patients. All 474 patients underwent nephrectomy including a group of 118 (25%) patients (24 pT2, 90 pT3, and 4 pT4) who underwent preoperative embolization of the renal artery. To compare treatment outcomes in embolized patients with RCC, a group of 116 (24%) nonembolized patients with RCC was selected. This group was matched for sex, age, stage, tumor size, and tumor grade, with the embolized patients (p<0.01). All important prognostic factors were studied as to their influence on survival by the treatment group. The overall 5- and 10-year survival was 62% and 47%, respectively. The 5- and 10-year survival rates were significantly better (p<0.01) for patients with pT2 than for those with pT3 tumors (79% vs. 50% and 59% vs. 35%, respectively). Involvement of regional lymph nodes (N+) was an important prognostic factor for survival in patients with pT3 tumors. The 5-year survival for pT3 N+ was 39%, compared with 66% in those with pT3N0 (p<0.01). Preoperative embolization was also an important factor influencing survival. The overall 5- and 10-year survival for 118 patients embolized before nephrectomy was 62% and 47%, respectively, and it was 35% and 23%, respectively, for the matched group of 116 patients treated with surgery alone (p = 0.01). The most important finding of this study was an apparent importance of preoperative embolization in improving patients' survival. This finding needs to be interpreted with caution and confirmed in a prospective randomized trial.