Outcomes Following Partial Nephrectomy by Tumor Size

Purpose: Pathological evaluation of renal tumors treated with ablative and observational therapy is often limited and renal tumor size may be the only prognostic index available. We established long-term survival in patients following partial nephrectomy according to tumor size. Materials and Methods: A retrospective review of our nephrectomy registry was performed to identify patients who underwent partial nephrectomy for localized (NX/N0/cM0) solid renal tumors 7 cm or less at our institution between 1970 and 2004. Overall, cancer specific, distant metastasis-free and local recurrence-free survival was estimated using the Kaplan-Meier method and stratified according to tumor size in all tumors treated and in patients with pathologically confirmed renal cell carcinoma. Results: We identified 798 patients who underwent partial nephrectomy for a 7 cm or less renal tumor. Median patient age was 63.5 years and median tumor size was 3.0 cm. Renal cell carcinoma was present in 637 tumors (80%). Overall, cancer specific, metastasis-free and local recurrence-free survival significantly decreased with each 1 cm increase in size in all tumors treated and in those with pathologically confirmed renal cell carcinoma (each p <0.05). Conclusions: Partial nephrectomy is associated with durable cancer control in patients with renal tumors 7 cm or less, of which most represent renal cell carcinoma. Tumor size represents a valuable prognostic index in the absence of pathological evaluation of the entire tumor specimen. These results may be used for comparison against outcomes following ablative and observational therapy, for which tumor size is the only prognostic index available.