SIMPLE ENUCLEATION VERSUS PARTIAL NEPHRECTOMY IN THE CONSERVATIVE TRATMENT OF RENAL TUMOUR T1 N0 M0: ANALYSIS OF SATURN STUDY

Aim of the study: The excision of the renal tumor with a substantial margin of healthy parenchyma is considered the gold standard technique for partial nephrectomy (PN). However, simple enucleation showed excellent results in some retrospective series. The purpose of the study was to compare the oncologic outcomes after standard PN and simple enucleation. Material and methods: We retrospectively analyzed 1519 patients who underwent standard PN or simple enucleation for localized renal cell carcinoma (RCC) in 16 academic centres between 1997 and 2007. Standard PN was performed in 982 (64.7%) patients, while simple enucleation was performed in the remaining 537 (35.3%) cases. Local recurrence and cancer-specific survival (CSS) were the main outcomes of this study. The Kaplan-Meier method was used to calculate survival functions, and differences were assessed with the log-rank statistic. Univariable and multivariable Cox regression models addressed cancer-specific mortality. Results: The median follow-up of the patients undergoing traditional PN and simple enucleation was 51 ± 37.8 mo and 54.4 ± 36 mo, respectively (p = 0.08). The 5- and 10-yr CSS estimates were 93.9% and 91.6% after standard PN and 94.3% and 93.2% after simple enucleation (log rank p value 0.94). In multivariable analysis, the adopted technique for nephron-sparing surgery (NSS) was not an independent predictor of CSS (hazard ratio [HR]: 0.7; p = 0.53) when adjusted for the effect of the other covariates. The retrospective design and lack of central pathologic review were the main limitations of the present study. Conclusion: This is the first multicenter, comparative study showing the oncologic equivalence between the standard PN technique and simple enucleation