NBI cystoscopy increases in a population of smokers the likelihood of detecting bladder tumors? Preliminary experience
Recent reports have suggested that NBI cystoscopy is more effective than standard WLI cystoscopy for the detection of bladder tumors. Cigarette smoking is the primary risk factor for bladder cancer. The aim of this study was to evaluate, in the same patient, smokers ot not-smokers, the probability to increase our ability to detect bladder cancer comparing the predictive power NBI visible lesions cystoscopy versus white light visible lesions cystoscopy.
The secondary objective was to evaluate how the preoperative use
of NBI cystoscopy can increase the ability to detect bladder lesions in higher smokers (> 20 cigarette/die) vs fewer (< 20 cigarette/die) vs no-smokers
Materials and Methods
From June 2010 to April 2012, 797 consecutive patients, 423 male and 374 female, affected by suspected bladder cancer lesions, on the basis of the EAU Guideline 2010, were underwent to WL plus NBI cystoscopy. The mean age was 67.7 yrs. (range 46-88).
In our experience , 520 pts ( 65,2%) were smokers and 153 pts no-smokers . In the smokers group, 337 pts ( 64,8%) were higher (> 20 cigarette/die) than 183 pts (35,2%) fewer (< 20 cigarette/die) smokers.
The statistical analysis was oriented toward the evaluation of the efficacy of NBI vs WL cystoscopy. The two-proportion z-test for matched pairs has been conducted to determine whether the difference between the two proportions of positive results achieved by WL and by NBI is significant. The related confidence intervals have been calculated. In order to quantify how strong is the difference, OR and RR have been built up.
In our experience, in 797 patients, WL cystoscopy was used to identify 602 patients (75,5%) with suspicious lesions, while the use of NBI following WL allowed identifying a total of 785 patients (98.49%). The use of NBI cystoscopy, significantly increases by approximately 30% our predictive power to identify lesions not visible with WL cystoscopy.
In smokers, the use of NBI Cystoscopy increases by approximately 30% (p <0,000, IC-95% 0,19-0,26) the ability to detect lesions not otherwise visible with the only WL cystoscopy (OR 25.9 and RR 1.28).
In higher smokers group the use of NBI Cystoscopy increases by approximately 25% (OR 21,8 and RR 1,24 ) than 35% in fewer smokers group (OR 34,8 and RR 1,34) the ability to detect lesions not otherwise visible with the only WL cystoscopy. In no smokers group we observed, following NBI cystoscopy, a relative risk approximately 30% (OR 15.9 and RR 1.29) to detect lesions not otherwise visible with the only WL cystoscopy.
This is the first study in the literature in a large patient’s cohort, in which the ability of NBI cystoscopy to increase the ability to detect suspicious bladder lesions was compared with the use of WL cystoscopy alone in the same smokers or no-smokers patients. In smokers patients, the use of NBI cystoscopy, significantly increases by approximately 30% our predictive power to identify lesions not visible with WL cystoscopy . In the others subgroups, fewer, no smokers and higher smokers groups, we observed , following NBI cystoscopy, a significantly increased relative risk, approximately 35%, 30% and 25%, respectively, to detect lesions not otherwise visible with the only WL cystoscopy.Argomenti: