[Narrow band imaging-assisted cystoscopy in bladder tumor follow-up: Can more tumors be identified?]

Narrow band imaging (NBI) is a new technique of urethrocystoscopy, in which only certain wavelengths [415 (blue) and 540 nm (green)] are used to detect urothelial carcinoma. The aim of the investigation was to analyze the potential benefit of NBI in the follow-up of patients with transitional cell carcinoma of the bladder.

Between August 2013 and July 2014, patients with a history of transitional cell carcinoma of the bladder, presenting for follow-up cystoscopy, were either examined via flexible white light endoscopy (WLE) plus second look WLE (n = 251, controls) or second look NBI cystoscopy alone (n = 251) in the same session.

Rates of recurrences were similar in the two groups [NBI 68 (27.1 %); WLE 70 (27.9 %)]. NBI after WLE identified more tumors in 13 patients (5.69 vs. 3.92). In 8 patients NBI showed no vascularization in suspicious areas. In the control arm, in 8 cases more tumors (3.75 vs. 3.13) were identified in the second WLE.

The additional use of NBI in the follow-up cystoscopy of patients after transurethral resection of nonmuscle invasive bladder cancer leads to an increased number of detected tumors; however, a part of the additionally detected tumors can be explained by the double examination. NBI appears to provide information in individual cases whether transurethral resection of bladder tumor is necessary.