Similar to PDD, NBI does not distinguish bladder cancer grade. The detection of CIS was significantly improved by NBI over WLC (100% vs 83% sensitivity) in a study of 427 patients. Another multicenter, prospective study reported a significantly increased sensitivity for the detection of CIS from 50% for WLC to 90% for NBI in 104 patients. In a recent, single-center, randomized, controlled trial to assess whether NBI improved TUR of bladder tumors in 254 patients with 2-year follow-up, a reduced recurrence rate (22% vs 33%; P=.05) and improved recurrence-free survival (22 vs 19 months; P =.02) were reported by NBI compared with WLC.