['To compare the oncological outcomes of patients who underwent elective partial nephrectomy (PN) or radical nephrectomy (RN) for clinically organ-confined renal masses ≤7 cm in size (cT1).', 'The records of 3480 patients with cT1N0M0 disease were extracted from a multi-institutional database and analyzed retrospectively.', 'In patients who underwent PN, the risk of clinical understaging was 3.2% in cT1a cases and 10.6% in cT1b cases. With regard to the cT1a patients, the 5- and 10-year cancer-specific survival (CSS) estimates were 94.7% and 90.4%, respectively, after RN and 96.1% and 94.9%, respectively, after PN (log-rank test: P = 0.01). With regard to cT1b patients, the 5-year CSS probabilities were 92.6% after RN and 90% after PN, respectively (log-rank test: P = 0.89). Surgical treatment failed to be an independent predictor of CSS on multivariable analysis, both for cT1a and cT1b patients. Interestingly, PN was oncologically equivalent to RN also in patients with pT3a tumours (log-rank test: P = 0.91).'] Is elective partial nephrectomy equivalent to radical nephrectomy in patients with clinical T1 renal cell carcinoma : results of a retrospective , comparative , multi-institutional study?