Comparison of nephron-sparing surgery in central versus peripheral renal tumors

To determine the feasibility of nephron-sparing surgery (NSS) in patients with centrally located tumors.

A retrospective cohort study of 118 patients who underwent NSS between 1993 and 2002 (35 patients with centrally located tumors and 83 with peripherally located tumors) was performed. Kaplan-Meier curves were constructed to evaluate freedom from local recurrence and disease-specific survival in patients with conventional histologic subtype tumors. The Wilcoxon test was used to compare the curves (two-tailed P < or =0.05 was considered to be statistically significant).

Intraoperatively, in patients with centrally located tumors, the need to close the collecting system (P = 0.035) and for blood transfusions (P = 0.033) was greater. Two perioperative deaths occurred in patients with peripherally located tumors. Two patients with centrally located tumors subsequently underwent nephrectomy. Of the patients with centrally located tumors, 1 patient had a positive margin, 2 patients had local recurrence, and 1 patient developed metastasis. No positive surgical margins or local recurrence was found in patients with peripherally located tumors, although 4 patients developed distant metastasis. Kaplan-Meier curves for patients with conventional histologic subtype tumors demonstrated a statistically significant difference for local recurrence (P = 0.04), but not for survival (P = 0.71). The mean follow-up time was 38.8 and 43.8 months for patients with centrally located and peripherally located tumors, respectively.

NSS can be used to postpone, or eliminate the need for, nephrectomy in 94.3% of patients with centrally located tumors and can achieve oncologic disease control similar to that for exophytic lesions. These data indicate that NSS should be considered even for patients with centrally located tumors, taking into account that performing such surgery is a challenging task.