OPTICAL COHERENCE TOMOGRAPHY (OCT) FOR THE DIAGNOSIS OF UROTHELIAL BLADDER CANCER: SENSITIVITY AND SPECIFICITY COMPARED TO WHITE LIGHT CYSTOSCOPY

Background/Aims: Emerging novel optical imaging techniques with cancer-specific molecular imaging agents offer a powerful and promising platform for cancer detection and resection. White-light cystoscopy and random bladder biopsies remain the most appropriate but nonetheless suboptimal diagnostic technique for bladder cancer, which is associated with high morbidity and recurrence. However, white-light cystoscopy has intrinsic shortcomings. Although current optical imaging technologies hold great potential for improved diagnostic accuracy, there are few imaging agents for specific molecular targeting. Carbonic anhydrase IX (CAIX) plays a pivotal role in tumorigenesis and tumor progression with potential value as an imaging target. Here, we investigated the feasibility of CAIX as a target and validated the diagnostic performance and significance of CAIX as an imaging agent. Methods: We first analyzed the data from The Cancer Genome Atlas (TCGA). Pairs of samples comprising bladder cancer and adjacent normal tissue were collected. All tissue samples were used for real-time PCR and immunohistochemistry to compare CAIX expression in normal and cancer tissue. Using blue-light cystoscopy, we observed the optical distribution of fluorescently labeled CAIX antibody in freshly excised human bladders and obtained random bladder biopsies to assess sensitivity and specificity. Results: The TCGA data revealed that CAIX expression was significantly higher in bladder cancer specimens than in normal tissue. The outcome was similar in quantitative real-time PCR analysis. In immunohistochemical analysis, bladder cancer specimens classified in four pathological subtypes presented a variety of positive staining intensities, whereas no benign specimens showed CAIX staining. Using blue-light cystoscopy, we distinguished bladder cancers that were mainly papillary, some variants of urothelial carcinoma, and less carcinoma in situ, from benign tissue, despite the presence of suspicious-appearing mucosa. The sensitivity and specificity for CAIX-targeted imaging were 88.00% and 93.75%, respectively. Conclusions: CAIX-targeted molecular imaging could be a feasible and adaptive alternative approach for the accurate diagnosis and complete resection of bladder cancer.

Download Full-text

Can urologists accurately stage and grade urothelial bladder cancer by assessing endoscopic photographs?

Journal of Telemedicine and Telecare ◽

10.1177/1357633x17727773 ◽

2017 ◽

Vol 24 (9) ◽

pp. 603-607 ◽

Cited By ~ 5

Author(s):

Snir Dekalo ◽

Haim Matzkin ◽

Nicola J Mabjeesh

Keyword(s):

Bladder Cancer ◽

Sensitivity And Specificity ◽

Transurethral Resection ◽

Bladder Tumour ◽

Intravesical Therapy ◽

Low Grade ◽

Tumour Stage ◽

Urothelial Bladder Cancer ◽

Urothelial Bladder ◽

Muscle Invasive

Introduction Assessment of urothelial bladder cancer during cystoscopy or transurethral resection of bladder tumour has a significant impact on the urologist's decision-making: treatment with simple outpatient fulguration, required depth of resection, and need of immediate post-surgical intravesical therapy. These choices depend heavily on the urologist's ability to accurately assess pre-biopsy tumour stage and grade. The aim of the study was to determine whether evaluation of photographs taken during transurethral resection of bladder tumour can reliably characterize a tumour’s stage and grade. Methods Smartphone photographs of 50 urothelial bladder cancer cases were taken at the beginning of transurethral resection of bladder tumour and individually presented to seven senior urologists. All urologists were blinded to the final pathological report and to any other urological evaluation. Each one was asked to rate the tumour as low vs high grade and noninvasive Ta vs noninvasive T1 or muscle invasive. Results were compared with final pathology. Individual appraisal and the majority's opinion were evaluated. Results Urologists have correctly predicted tumour stage and grade in 63.5% of cases (222 of 350, average of 32 out of 50 accurate assessments). The final majority assessment was correct in 40 of 50 cases (80%). Sensitivity and specificity of the final results for the diagnosis of T1 or higher were 80% and 88.6%, respectively. Sensitivity and specificity for Ta low grade were 83.3% and 80%, respectively. Conclusions To the best of our knowledge, this is the first documented attempt to evaluate urologists' ability to assess urothelial bladder cancer stage and grade using endoscopic photographs. Urologists can usually identify stage and grade of urothelial bladder cancer but accuracy increases when multiple senior urologists examine the same photographs and achieve majority consensus. Presenting photographs of urothelial bladder cancer to a team of urologists may lead to an excellent decision regarding type and extent of surgical treatment and substantiate appropriate post-surgical management.

Download Full-text