Diagnosis of bladder cancer with microelectromechanical systems-based cystoscopic optical coherence tomography

To examine the utility and potential limitations of microelectromechanical systems-based spectral-domain cystoscopic optical coherence tomography (COCT) so as to improve the diagnosis of early bladder cancer.

An optical coherence tomography catheter was integrated into the single instrument channel of a 22F cystoscope to permit white-light-guided COCT over a large field of view (4.6 mm wide and 2.1 mm deep per scan at 8 frames/s) and 10-microm resolution. Intraoperative COCT diagnosis was performed in 56 patients, with a total of 110 lesions examined and compared with biopsied histology.

The overall sensitivity of COCT (94%) was significantly higher than cystoscopy (75%, P = .02) and voided cytology (59%, P = .005); the major enhancement over cystoscopy was for low-grade pTa-1 cancer and carcinoma in situ (P < .018). The overall specificity of COCT (81%) was comparable to voided cytology (88.9%, P = .49), but significantly higher than cystoscopy (62.5%, P = .02).

The microelectromechanical systems-based COCT, owing to its high resolution and detection sensitivity and large field of view, offers great potential for "optical biopsy" to enhance the diagnosis of nonpapillary bladder tumors and their recurrences and to guide bladder tumor resection.