Study Type – Diagnostic (exploratory cohort) Level of Evidence 2b
To evaluate whether narrow-band imaging cystoscopy (NBIC) can identify bladder tumour suspected on follow-up white-light cystoscopy (WLC) after intravesical bacille Calmette-Guérin (BCG) therapy, as BCG causes an intense reaction in the bladder, appearing as red lesions on WLC, which might be residual tumour or BCG-induced inflammation.
PATIENTS AND METHODS
Sixty-one patients with high-risk non-muscle-invasive bladder tumours were evaluated 3 months after starting induction BCG therapy. All patients had abnormal erythematous lesions on WLC, suspected to be residual carcinoma in situ. After WLC, they were evaluated by NBIC, urine cytology and biopsy, followed by transurethral resection of all visible lesions.
Of the 61 patients, 22 (36%) had residual tumour. NBIC correctly identified tumour in 21 patients, but another 10 had unnecessary biopsy (NBIC positive, negative biopsy). Only one of 30 patients who had negative NBIC findings had tumour. NBIC outperformed urine cytology in detecting residual tumour after BCG therapy.
NBIC appears to better identify patients who have suspected residual tumour on follow-up WLC at 3 months after BCG therapy.