When performing TURBT there are many details we need to be aware of. These include the configuration of the tumor (flat, sessile, or papillary), its location, size, the number of tumors, and the pathologic assessment must be elaborate and provide information about the stage, grade, lymphovascular invasion, variant histology, and tissue biomarkers.
NMIBC is a highly heterogenous disease with varying rates of recurrence and progression. Low grade Ta disease has a recurrence rate of 55% with stage progression of 5%, while high grade T1 disease has a recurrence rate of 50%, and 20% of them progress to muscle invasive disease (MIBC). Risk stratification enables us to personalize treatment decisions. Unfortunately, the current predictive models are based on the pathologic features of the tumor, but they underperform.
Proper staging is essential in NMIBC. Restaging TURBT 4-6 weeks after diagnosis for high risk NMIBC, or for cases where no muscle was present in the pathology is critical. Approximately 30-50% residual tumor is found at restaging TURBT, leading to a risk of 20-49% for upstaging. This information is obviously important before commencing intravesical therapy. Restaging TURBT can significantly change management decision, and affect whether we give BCG, and whether we perform radical cystectomy. Restaging TURBT was found to be the only significant predictor of five-years status of no evidence of disease.1 Re-TURBT has also been shown to have a positive impact on recurrence, progression, cancer specific survival, and overall survival in patients who did not have muscle in the pathology of the first TURBT. 2
The next topic discussed was the role of enhanced cystoscopy. According to the American Urologic Association (AUA) guidelines blue light cystoscopy should be offered to patients with NMIBC at the time of TURBT to increase the detection rate and decrease recurrence rates (Grade B). The AUA guidelines also recommend narrow band imaging (NBI) to increase the detection and decrease recurrence (Grade C). 3 The rationale for enhanced cystoscopy is that optical enhancement at the time of resection, as well as repeat resection of high risk tumors have highlighted the importance of seeing and identifying all the tumors, in the initial resection and on the tumor recurrence rate. Optimization of tumor resections carries significant implications for oncological care – early cystectomy, intravesical therapy, and clinical trials.
NBI works by filtering white light into specific light wavelengths that are absorbed by hemoglobin providing enhanced visualization of capillary networks and mucosal morphology. In a trial comparing white light cystoscopy and NBI, no significant difference in the recurrence rate at 12 months was seen (27.1% for white light cystoscopy vs. 25.4%for NBI, p=0.585). However, in the low risk patients, the recurrence rates for white light cystoscopy at one year was 27.3% vs. 5.6% for NBI, p=0.002). 4
Blue light cystoscopy (Cysview) has been extensively studied to investigate improvement in detection of bladder tumors vs. white light cystoscopy. There have been six multi-center phase 3 trials in the US, Canada, and Europe analyzing its role. In a large study by Stenzl A. 5 in patients with Ta or T1 disease, 16% of Ta tumors, 13% of T1 tumors and 46% of carcinoma in-situ (CIS) was diagnosed with the use of blue light cystoscopy only! In another meta-analysis by Burger et al.6 24.9% of patients with more than one tumor were detected with blue light cystoscopy only, and 27% of patients with CIS were detected with Cysview only. In a study assessing time to recurrence, Cysview demonstrated a longer time to recurrence (16.4 months) when compared to white light cystoscopy (9.4 months), p=0.04. 7 Another meta-analysis demonstrated that Cysview reduces the rate of progression (6.8%) compared to white light cystoscopy (10.7%), p=0.01. 8
Cysview is an FDA approved optical imaging agent indicated for the use in the cystoscopic detection of NMIBC in patients suspected or known to have a lesion on the basis of a prior cystoscopy. It is used with the KARL STORZ-D light C Photodynamic Diagnosis (PDD) system to perform cystoscopy with the blue light setting as an adjunct to the white light setting. It must be instilled in the bladder one hour prior to the cystoscopy or TURBT, and it cannot be used for upper tract disease.
Next, Dr. Bivalacqua discussed on the differences between monopolar and bipolar TURBT. In a single center, parallel arm, randomized controlled trial comparing these two techniques, the only difference found was the rate of severe cautery artifacts, which were higher in the monopolar arm. No differences were seen in the incidence of obturator jerk, bladder perforations, resection time, and rates of transfusion. 9
Lastly, the comparison between conventional and en-block resection TURBT as discussed by Dr. Bivalacqua. Conventional TURBT has been widely used over decades, but it has multiple drawbacks. These include tumor implantation through fragmentation, high rates of missing detrusor muscle, and incomplete resections, as well as thermal damage. En-block resection theoretically offers three goals: improvement of resection quality (higher rates of incorporating detrusor muscle in the specimen), lowering perioperative complications, and possibly decreasing recurrence rates. To date, there is no randomized controlled trial to demonstrate the superiority of en-block resection over conventional TURBT. The retrospective data on perioperative complications are the same in both techniques and data on freedom of recurrence is lacking.
In summary, enhanced cystoscopy has significantly reduced recurrence rates in NMIBC following TURBT. En-block resection and various surgical approaches (monopolar, bipolar) are non-inferior to conventional TURBT, and prospective trials are needed to learn if any advantage exists.
Presented by: Trinity Bivalacqua, John Hopkins, United States
- Sfakianos and Herr et al. J Urol 2013
- Gontero and Paou et al. BJU 2015
- Chang S et al. AUA NMIBC GUIDELINES 2016
- Naito S et al. Eur Urol 2016
- Stenzl A. et al. J Urol 2010
- Burger et al. Eur Urol 2013
- Grossman et al. J Urol 2012
- Kamat et al. Bladder Cancer 2016
- Venkatramani V et al. J Urol 2014