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Nephron sparing surgery for appropriately selected renal cell carcinoma between 4 and 7 cm results in outcome similar to radical nephrectomy.

PURPOSE
We compared outcomes between patients treated with nephron sparing surgery (NSS) without imperative indications for renal preservation and radical nephrectomy (RN) for 4 to 7 cm renal cell carcinoma (RCC).


MATERIALS AND METHODS
We identified 91 patients treated with NSS and 841 patients treated with RN for 4 to 7 cm RCC between 1970 and 2000. Cancer specific, distant metastases-free and recurrence-free survivals were estimated using the Kaplan-Meier method.


RESULTS
Cancer specific survival rates at 5 years for patients treated with NSS and RN for 4 to 7 cm RCC were 98% and 86%, respectively. On univariate analysis patients treated with RN for 4 to 7 cm RCC were more likely to die of RCC compared to patients treated with NSS. However, after adjusting for features associated with death from RCC including stage, grade, histological tumor necrosis and histological subtype, this difference was no longer statistically significant (risk ratio 1.60, 95% CI 0.50-5.12, p = 0.430). Distant metastases-free survival rates at 5 years for patients treated with NSS and RN were 94% and 83%, respectively. On univariate analysis patients treated with RN were more likely to have tumors that metastasized compared to patients treated with NSS, although this difference was no longer significant after adjusting for the features listed previously (risk ratio 1.76, 95% CI 0.64-4.83, p = 0.273). Recurrence-free survival rates at 5 years for patients treated with NSS and RN were 94% and 98%, respectively. On univariate analysis patients treated with RN were less likely to have recurrence compared to patients treated with NSS (risk ratio 0.32, 95% CI 0.12-0.85, p = 0.022).


CONCLUSIONS
There were no statistically significant differences in cancer specific survival and distant metastases-free survival between patients treated with NSS and RN for 4 to 7 cm RCC after adjusting for important pathological features. NSS for 4 to 7 cm RCC results in excellent outcome in appropriately selected patients.