Improvements in Endoscopic Urothelial Tumor Visualization

Mission

Through worldwide collaboration, CROES seeks to assess, using evidence based scientific methodology, the various aspects of clinical endourology.

Vision

By applying rigorous scientific evaluation to the field of clinical endourology, CROES will enable all urologic surgeons to bring to their patients the most effective and efficient care possible.

Projects

Contact

For more information please contact Sonja van Rees Vellinga (info@croesoffice.org).

Improvements in Endoscopic Urothelial Tumor Visualization

Guido Kamphuis, Theo de Reijke, and Jean de la Rosette

The Clinical Research Office of the Endourological Society (CROES) is proud that, in partnership with Storz, two new exciting projects will be launched. The new projects will focus on a new technique for better detection for the lower and upper urinary tract (UUT) tumors.

Bladder cancer had, in 2012, an estimated incidence of 151.2 new cases per 100,000 persons, the fifth cancer in Europe. The male to female ratio is about 4:1. Mortality is 52.4 per 100,000. ¹

In the United States, it has been estimated that in 2013, 72,570 persons will receive a diagnosis of bladder cancer with a male to female ratio of about 3:1. ² The majority of all urinary tract cancers are of the urothelial carcinoma (UC) subtype. Of all primary UCs, approximately 70% to 80% is first seen as a nonmuscle-invasive bladder cancer (NMIBC) and the remainder as muscle-invasive disease. Among the NMIBC, 70% are T_a lesions, 20% are T₁, and 10% are carcinoma in situ (CIS), according to the 2002 Tumor Node Metastasis classification proposed by the Union International Contre le Cancer. ³

Eighty to 90% of patients present with painless hematuria, either microscopic or macroscopic. Also, irritative lower urinary tract symptoms can be a sign of CIS or bladder tumor. Sometimes, patients present with symptoms of progressive disease such as a palpable mass in the lower abdomen, weight loss, or bone pain.

White light (WL) cystoscopy is the reference standard for the detection of bladder tumor(s) in combination with urine cytology. The standard initial treatment for bladder cancer is transurethral resection of all visible lesions in the bladder (TURB). Although patients with NMIBC have a relatively good prognosis in terms of cancer-specific survival, there is a chance of approximately 75% that the cancer will recur. ⁴ Remarkably, in up to 45% of patients, the recurrence presents already at the first follow-up cystoscopy at 3 months after TURB. ⁵ One possible explanation is that these recurrences are partly persisting tumors or overlooked tumors at TURB.

If cystoscopic visualization of bladder tumors can be improved, a better TURB and more complete TURB can be performed resulting in a lower recurrence rate. To achieve a better TURB, new developments in addition to the traditional WL cystoscopy have and are being introduced.

Photodynamic diagnosis (PDD) after intravesical instillation of 5-aminolevulinic acid or hexaminolevulinic acid (HAL) has been studied most extensively. A systematic review and meta-analysis demonstrated a higher sensitivity for PDD compared with WL cystoscopy. ⁶ A large, multicenter, prospective randomized trial comparing HAL fluorescence-guided TURB with standard TURB reported an absolute recurrence rate reduction of 9% within 9 months. ⁷ The drawback of this technique is the intravesical instillation before cystoscopy and extra equipment necessary, which leads to increased costs.

Narrow band imaging (NBI) is an optical imaging enhancement technique designed for endoscopy to enhance the contrast between mucosal surfaces and microvascular structures without the use of intravesical dyes. One prospective study demonstrated an improvement in the detection rate with NBI compared with WL cystoscopy. ⁸ At this moment, the CROES is conducting a randomized controlled trial (RCT) comparing WL and NBI supported TURB that should define the role of NBI in preventing recurrences. The study is close to the anticipated number of randomized patients.

Very recently, Karl Storz has presented their SPIES system. SPIES is an acronym for Storz Professional Image Enhancement System. The digital cystoscopy signal is processed offering a virtual chromoendoscopy. By changing the spectrum, better color contrast can be identified on the video screen. Changing the spectrum, the contrast differences can be adjusted to the clinical situation. A multicenter, international study to compare use of Storz SPIES vs WL imaging during TURB to assess recurrence of bladder cancer in terms of safety and efficacy will be conducted in 10 European centers. Also, SPIES will be included in the upcoming CROES UUT tumors registry study. The treatment of this rare condition is receiving increased interest, especially since renal-sparing surgery has also become available here. Retrograde intrarenal surgery (RIRS) is very successful using digital technology for diagnosis and laser technology for tumor treatment. A major limitation to perform this safely is a proper diagnosis as well as adequate tools for follow-up. With the application of SPIES, we estimate that we will be able to visualize UUT tumors more completely and use SPIES also during follow-up to better visualize possible recurrences.

The Storz Company supports this registry that will position the use of RIRS for UUT tumors. This registry will also evaluate the different treatment options for UUT tumors and will assess patient characteristics and outcomes. With this wealth of information, we will have access to prospective data collected throughout the world and may as such provide new insights in diagnostics, treatment, and follow-up. CROES is most happy that we have been able to launch this important registration with the kind support from the Storz Company.

CROES is leading the way to investigate which are the best imaging modalities for the diagnosis and treatment of nonmuscle-invasive cancer in the urinary tract by initiating the RCT and registry to solve these questions, and this could be the optimal platform to be involved in this area of research. All centers are invited to join the CROES UUT tumors registry study, which will be launched at the end of 2013. Please sign up through info@croesoffice.org