Oncological and functional efficacy of nephron-sparing surgery versus radical nephrectomy in renal cell carcinoma stages ≥cT1b: a single institution, matched analysis.

Introduction: The purpose of this paper is to compare oncological outcomes of partial nephrectomy (PN) versus radical nephrectomy (RN) in renal cell carcinoma (RCC) clinical stages ≥T1b, in a retrospective propensity-score matched cohort of a high-volume, tertiary referral center. This paper also aims to compare renal function and complication rates between groups.

Material and methods: Our single-institution RCC database was queried to select patients with clinical stages defined by tumor size (T), lymph nodes(N), and metastasis (M) scores of T1b-4 N0 M0, that underwent PN or RN between 2000 and 2014. All images of patients that underwent RN were reviewed, and only patients deemed eligible for PN were included. Medical records were reviewed to obtain data on tumor characteristics, comorbidities, renal function, and complications. After propensity score matching, 152 patients (76 per group) were included in the final analysis. Primary outcomes were cancer specific survival (CSS), overall survival (OS), and clinical progression-free survival (CPFS). Secondary outcomes were renal function preservation and post-operative complication rates.

Results: Groups were propensity-score matched. The only parameters that were significantly different between groups were the median follow-up time (RN: 79 months, range 24.1-100.5 vs. PN: 38.5 months, range 20.5-72.1) and a better performance status in the RN group (p = 0.002). The five-year CPFS, CSS, and OS rates were 77.2%, 90.5%, and 86.4%, respectively, in the RN group, and 83.6%, 91.1%, and 82.0%, respectively, in the PN group (p = 0.33, p = 0.55, and p = 0.33, respectively). In the multivariate Cox model, the surgical method was not an independent predictor of CPFS, CSS, or OS. The RN group showed a significantly greater reduction in estimated glomerular filtration rate (RN: 14.1 vs. PN: 5.4 ml/min per 1.73 m²; p <0.03). There was no significant difference in complication rates between the two groups (p = 0.3). The main limitations of this study were its retrospective design and the medium-term follow-up.

Conclusions: Our results demonstrated the efficacy and safety of PN in patients with RCC in clinical stages ≥T1b. We observed no significant difference in oncological outcomes between the PN and RN groups at medium-term follow ups. The surgical method did not influence these outcomes. Renal function was preserved significantly more frequently in the PN than in the RN group, but the groups had similar complication rates.These findings suggested that PN could be considered an oncologically safe procedure for treating large RCC tumors; thus, PN should always be considered, when technically feasible, regardless of tumor stage.