Objectives: A retrospective clinical analysis was performed over a time period of 10 months while aiming to establish the impact of narrow band imaging (NBI) cystoscopy and transurethral resection of bladder tumors (TURBT) in cases of carcinoma in situ (CIS).
Materials and methods: CIS tumor cells are characterized by a high cytological grade, a certain degree of cyto-nuclear pleomorphism, large, irregular, hyperchromatic nuclei, high nuclear/cytoplasmatic ratio and mitotic figures. One hundred thirty-nine patients were consecutively diagnosed with non-muscle invasive bladder cancer (NMIBC) based on standard white light cystoscopy (WLC) and NBI vision. Urinary cytology was performed in cases of flat lesions suspected by either type of cystoscopy before the TURBT staging. Conventional endoscopic resection was performed for all white light (WL) visible lesions and NBI-guided TURBT exclusively for the observed tumors.
Results: At subsequent pathological analysis, 13 CIS patients were confirmed. NBI cystoscopy emphasized a superior diagnostic accuracy as compared to WLC concerning the cases' (92.3% versus 69.2%) as well as lesions' (93.75% versus 71.9%) detection rates. NBI-TURBT provided a higher proportion of additional tumors' cases (53.8% versus 15.4%) when compared to classical resection but was marked by an increased frequency of false-positive results (18.9% versus 11.5%). Urinary cytology displayed an 84.6% sensitivity rate.
Conclusions: NBI cystoscopy and resection substantially ameliorated the CIS-related diagnostic accuracy within a parallel to the standard endoscopic approach at the cost of a reduced specificity. NBI-TURBT was able to find more CIS patients as well as lesions, thus improving the sensitivity of standard resection and urinary cytology.