['To compare the outcomes of patients treated for upper tract urothelial carcinoma with either immediate nephroureterectomy (NU) or initial endoscopic management.', "The treatments of 108 patients (120 renal units) at the authors' institution were retrospectively reviewed and divided into two groups, i.e. those who received immediate NU and those who had conservative initial therapy, which included renal units solely treated with endoscopy with or without delayed NU. Overall and disease-specific survival (DSS) were compared between the treatment groups.", 'There were 48 low-grade tumours, of which 27 (56%) were managed conservatively and 21 (44%) by immediate NU. Seven patients treated conservatively had stage or grade progression and had delayed NU. The mean (sd) DSS at 5 years in patients with low-grade disease was equally good for conservative treatment and immediate NU, at 86.2 (9.1)% vs 87.4 (8.4)% (P = 0.909). There were 68 high-grade tumours, of which 12 (18%) patients had conservative management and 56 (82%) had immediate NU. Among the former, seven of 12 had a solitary kidney and three had bilateral disease. In patients managed endoscopically, four of 30 (13%) required delayed NU. The DSS for the conservative and immediate NU groups were 68.6 (18.6)% vs 75.0 (8.1)% (P = 0.528).'] Does conservative management in selected patients with upper tract urothelial carcinoma compare favourably with early radical surgery?