Narrow band imaging for detecting residual/recurrent cancerous tissue during second transurethral resection of newly diagnosed non‐muscle‐invasive high‐grade bladder cancer

Abstract

To determine if narrow-band imaging (NBI) can be used to detect high-grade cancerous lesions missed with the white light at the time of a second transurethral resection (TUR) of high-grade non-muscle-invasive bladder cancer (NMIBC). Consecutive patients with newly diagnosed high-grade NMIBC were enrolled in a prospective observational study. Patients with incomplete resection or absence of muscle tissue in the specimen were excluded. About 1 month after the first TUR, NBI cold-cup biopsies were taken from areas suspicious for urothelial cancer at the end of an extensive white-light second TUR protocol including: (i) resection of the scar of the primary tumour; (ii) resection of any overt or suspected urothelial lesions; and (iii) six random cold-cup biopsies of healthy mucosa. In 2008, 47 consecutive patients were recruited after giving written consent (median age 62 years, range 49-83, 39 men and eight women). Nine patients (19%) had macroscopic or microscopic high-grade NMI urothelial cancer, whereas one was reassessed as having muscle-invasive disease at the white-light second TUR plus the six random biopsies. NBI biopsies were taken in 40 of the 47 patients and detected six more patients with high-grade cancerous tissue (13%). In all 16 of the 47 patients (34%) were found to have residual/recurrent cancer using our extensive protocol of second TUR followed by NBI biopsies. Adding NBI biopsies at the end of an extensive second TUR protocol in patients with newly diagnosed high-grade NMIBC can lead to the identification of patients with otherwise missed high-grade residual/recurrent urothelial carcinoma.