Safety and efficacy of partial nephrectomy for all T1 tumors based on an international multicenter experience

Purpose: We compared cancer specific survival of patients undergoing partial and radical nephrectomies for T1N0M0 renal tumors according to tumor size in a large multicenter series. Materials and Methods: A retrospective analysis of 1,454 patients undergoing partial or radical nephrectomy for T1N0M0 renal tumors from 7 international academic centers was performed. Data were obtained for each patient including TNM stage (determined according to the 2002 TNM criteria), tumor size, type of surgery (partial versus radical nephrectomy) and cancer specific survival. Recurrence events were recorded when available. Results: Partial and radical nephrectomies were performed in 379 (26.1%) and 1,075 (73.9%) cases, respectively. Mean followup +/- SD was 62.5 +/- 51.8 months. Recurrence data were available on 544 patients. There were no significant differences in local or distant recurrence rates between patients undergoing partial or radical nephrectomy for either T1a (p = 0.6) or T1b tumors (p = 0.5). For patients with T1a tumors, there was no significant difference in the rate of cancer specific deaths between the partial (314) and radical (499) nephrectomy groups (2.2% versus 2.6%, respectively, p = 0.8). For patients with T1b tumors there was also no significant difference in the rate of cancer specific deaths between patients undergoing partial (65) and patients undergoing radical (576) nephrectomy (6.2% versus 9%, respectively, p = 0.6). Conclusions: Partial nephrectomy is becoming the gold standard for renal tumors less than 4 cm but this treatment is much more controversial for larger T1 tumors. This large multicenter study suggests that it is safe to expand the indications of partial nephrectomy to include patients with T1N0M0 tumors up to 7 cm. However, careful patient selection remains necessary.