Primary Outcome Measures:
- Assessment of accuracy and positive predictive value of OCT for determining tumor stage correlated by histopathology [ Time Frame: Upon receipt of data ] [ Designated as safety issue: No ]
Secondary Outcome Measures:
- Correlate cystoscopic stage and grade,surgeon's interpretation of OCT images with histopathologic stage and grade [ Time Frame: Upon receipt of data ] [ Designated as safety issue: No ]
Bladder cancer is the fourth most common cancer in men and the eighth most common in women with approximately 60,000 new cases diagnosed every year. The highest occurrence of bladder cancer is found in industrialized countries such as the United States, Canada, Denmark, Italy and Spain. The incidence is three to four times higher in men compared with women, and the incidence rises with age. Among white men, the annual incidence after the age of 65 is approximately two per 1000 people and the lifetime chance of developing bladder cancer is over 3%.
The majority of patients have non-muscle invasive bladder cancer (cancer that has not spread into the bladder muscle) which can be controlled, but survival depends upon early detection of the cancer. In the 20 years following diagnosis, there is a recurrence rate (the cancer returns after treatment) of 50 to 75%, a progression rate (cancer recurs and is now invasive) of 10 to 40% and a death rate of 10 to 30%.
Optical coherence tomography (OCT) was first used to image human tissue in 1991 and has been developed for clinical applications since that time. OCT employs light (instead of sound waves) to obtain images in a manner analogous to B-mode ultrasonography performing real-time, 10-20 micron scale imaging, nearing the resolution of histopathology. OCT performs two- and three-dimensional imaging in biological tissues by directing harmless near infrared light onto the tissue and measuring the reflected or backscattered intensity of light as a function of depth. Direct comparisons have been performed between OCT and the current clinical technology with the highest resolution, high frequency ultrasound. OCT demonstrated superior performance both quantitatively and qualitatively. The potential clinical use of OCT in the bladder is closely related to cystoscopic imaging with white light. The complementary use of OCT with standard cystoscopy allows acquisition of real-time images of regions of interest at a depth of up to 2mm and a spatial resolution of ~10-20 um. Furthermore, OCT technology is fiber-optic based, which allows its relatively straightforward integration with small catheters and cystoscopes. OCT imaging is performed in real-time making it an attractive technology for implementation as a single episode point-of-care diagnostic, monitoring and surgical-guiding tool. Finally, as an optical imaging technology, OCT can be combined with other optical modalities such as absorption and polarization spectroscopy.