Variables Associated with the Use of Blue Light Cystoscopy Journal Club - Christopher Wallis & Zachary Klaassen

December 2, 2021

In this UroToday journal club, Christopher Wallis and Zachary Klaassen highlight a European Urology Focus publication entitled Underutilization of Blue Light Cystoscopy for Bladder Cancer in the United States. Blue light cystoscopy (BLC) for the management of nonmuscle invasive bladder cancer (NMIBC) is an evidence- and guideline-supported intervention that has been shown to increase cancer detection and decrease recurrence. The extent to which BLC is used has not been established. Drs. Wallis and Klaassen discuss this work which aimed to identify variables associated with the underuse of BLC in clinical practice.  


Christopher J.D. Wallis, MD, Ph.D., Assistant Professor in the Division of Urology at the University of Toronto.

Zachary Klaassen, MD, MSc, Urologic Oncologist, Assistant Professor Surgery/Urology at the Medical College of Georgia at Augusta University, Georgia Cancer Center

Read the Full Video Transcript

Christopher Wallis: Hello, and thank you for joining us for this UroToday Journal Club presentation. Today we are discussing a recent publication titled, Underutilization of Blue Light Cystoscopy for Bladder Cancer in the United States. I'm Chris Wallis, Assistant Professor in the Division of Urology at the University of Toronto. With me today is Zach Klaassen, Assistant Professor in the Division of Urology at the Medical College of Georgia. Here is the citation for this recent publication in European Urology Focus which is led by Dr. Lewicki and Dr. Shoag.

As many will know, blue light cystoscopy has been shown to improve the detection of non-muscle-invasive bladder cancer and decrease disease recurrence when employed at the time of transurethral resection of the bladder tumor. As a result of this, it is guideline-recommended, and additionally, the cost-effectiveness analysis supports the utilization of this approach.  However, there are some barriers to its use and these include availability, concerns regarding cost, as well as potential inconvenience or delays in the perioperative workflow.

As a result of these barriers, the authors postulated that there may be suboptimal uptake of the use of blue light cystoscopy. And so they sought to assess its utilization in patients undergoing bladder cancer care, using a large US-based data set, which captured medication administration. This was the Premier Healthcare Dataset, which is a large, hospital-based, all-payer sample. The authors identified patients undergoing what they termed index TURBTs, which is the first TURBT during the study period, and that was performed between the beginning of 2011 and March 2020. In total, this encompassed just over 158,000 procedures. The authors further utilized billing data to identify whether a blue light approach was used. They further extracted a number of covariates, including patient demographic details, tumor size, which were captured as a proxy via the use of CPT codes, the presence of concomitant CIS, insurance status, and US census region.

They then assessed the adoption of blue light cystoscopy on a monthly basis as the proportion of TURBTs performed with blue light cystoscopy among all TURBTs performed. They assessed this both overall, as well as a hospital and provider-level analysis. They further utilized segmented linear regression to estimate rates and time points of change in temporal trends. Beyond these temporal trend-based analyses, they further used logistic regression to identify the provider and hospital characteristics that were associated with blue light cystoscopy use. In particular, they used two proxies to assess the quality and volume of bladder cancer care. First, at the provider level, they assessed the use of a postoperative mitomycin C as a guideline-recommended bladder cancer behavior and included this in their regression models. They further examined both hospital and provider-level radical cystectomy volumes to account for the centralization of bladder cancer care.

At this point in time, I'm going to pass it over to Zach to walk us through the results.

Zachary Klaassen: Thanks, Chris. This figure is the results looking at blue light cystoscopy use over time, and we will focus on the inset figure here because it gives us some more detail in terms of the month being on the x-axis from January 2011 to January 2020, and on the y-axis is the percentage of TURBTs performed with blue light cystoscopy. So focusing on the smooth line, which is sort of an average of the TURBTs performed with BLC, you can see that the utilization was relatively low leading up to about 2016, and the dashed line represents the publication of the AUA non-muscle invasive bladder cancer guideline in October of that year, which highlighted that blue light cystoscopy should be used for detection of bladder tumors. Interestingly, we see an uptick at this point. And then in 2018, specifically in August, the authors note that there is no significant change in the rate of blue light cystoscopy use.

This figure looks at the percentage of hospitals with blue light cystoscopy availability. And you can see, again, a similar axis on the y- and x-axis here. And over time, a continued increase of availability of the procedure through 2020.  This figure looks at the percentage of providers using blue light cystoscopy at hospitals over time. And so we see that the providers were using it up until about mid-2018 when the provider-level use of blue light cystoscopy peaked, and then subsequently has decreased over the course of the last several years, up until the end of the time period of March 2020.

These are the results of the multivariable logistic regression model for patient receipt of blue light cystoscopy at the time of TURBT. We can see here that in terms of significant variables, males had a 1.2 odds ratio for receiving blue light cystoscopy, which was statistically significant. Looking here, compared to non-Hispanic white men, Hispanic and others were significantly increased odds of receiving blue light cystoscopy at the time of TURBT. In terms of decreased odds of receiving blue light cystoscopy, Medicare and self-pay patients, those with the higher Charlson comorbidity index, are less likely to receive blue light cystoscopy, an odds ratio of 0.85. And as expected carcinoma in situ, compared to those without CIS, an odds ratio of 2.18, as well as large and medium TURBT size versus small were more likely to receive blue light cystoscopy.  Again, several other variables which are of interest and quite statistically significant, academic hospitals versus nonacademic, a significant odds ratio of 1.88, hospital TURBT volume, a high volume greater than the 75th percentile, an odds ratio of 9.11, and hospitals that perform radical cystectomies in terms of the greater than 90th percentile versus less than the 90th percentile, the odds ratio of 2.44.

There is also another model looking at predictors of surgeons never using blue light cystoscopy. And not too surprising here, lower surgeon TURBT volume, less than the 75th percentile, which represents about 1 case a month or 12 cases per year, an odds ratio of 0.25. Low surgeon radical cystectomy volume, less than 75th percentile or 2 cases per year, an odds ratio of 0.29. And surgeons that did not use mitomycin C, the odds ratio of 0.61.

This is an interesting study and several important discussion points from this study. And based on this data, blue light cystoscopy is remarkably underutilized in the US, despite evidence supporting its benefits. As we saw, hospital-level acquisition of this technology has subsequently outpaced provider utilization, particularly after 2018. Lower surgeon volumes are less likely to use blue light cystoscopy, even in centers where blue light cystoscopy is available, and this suggests clustering of quality TURBT care among bladder cancer experts or high-volume surgeons. The authors did note several potential ways to increase the use of blue light cystoscopy pending the results of the PHOTO superiority trial, which may provide some additional evidence to increase engagement of providers as well as expansion of the technology into the flexible cystoscopy space, which may facilitate easier use.

So in conclusion, these findings demonstrate concerning underutilization and stagnation in the adoption of evidence and guideline-supported intervention, and ultimately, these data highlight a ready opportunity to improve population-level bladder cancer outcomes.

Thank you very much for your attention. We hope you enjoyed this UroToday Journal Club discussion.