[Does a tumor size higher than 7cm impact partial nephrectomy outcomes for the treatment of renal cancer?]. / Une taille tumorale supérieure à 7cm influence-t-elle les résultats de la néphrectomie partielle pour tumeur du rein ?

ABSTRACT

OBJECTIVE: To assess the impact of a tumor size higher than 7cm on partial nephrectomy (PN) outcomes compared to a tumor size ranging between 4 and 7cm and to compare this impact to one of the RENAL score. PATIENTS AND METHODS: Data from patients who underwent PN between 2006 and 2013 were retrospectively analysed. Patients with cT1b tumors and cT2 were included. Functional and oncological outcomes were compared. Analysis of the achievement of Trifecta (defined as a combination of warm ischemia time<25min, negative surgical margins and no perioperative complications) was performed according to the tumor size and the RENAL score. RESULTS: Among 334 PN, 57 patients were included, (41 cT1b and 16 cT2), with a median follow-up of 23.5 months (6-88). There was no difference between the groups regarding intraoperative parameters except for the conversion rate, which was higher in the cT2 group (30% vs. 4.3%; P=0.02). The cT2 group also presented higher renal function impairment at postoperative day 4 (P=0.04) which did not persist at 6 months. There was no significant difference in oncologic outcomes between the 2 groups. The rate of achievement of the Trifecta did not differ between cT1b and cT2 groups. Conversely, Trifecta rate was higher in case of low complexity renal masses (RENAL score 4-6) compared to complex renal tumors (RENAL score 7-9 and 10-12). CONCLUSION: Our results showed that a tumor size higher than 7cm had no impact on PN outcomes in selected tumors according to complexity scores such as the RENAL score. Furthermore, a lower RENAL score appeared to be significantly associated with the Trifecta achievement. LEVEL OF EVIDENCE 5.