AUA 2017: What is the Best Imaging and What Will We Be Using in the Future: Cystoscopy and Cross-Sectional Imaging?
In non-muscle invasive bladder cancer, blue light cystoscopy has been shown in a randomized trial to increase time to recurrence from 9 to 16 months. Logistical considerations include awake pre-operative catheterization and instillation of exogenous contrast agent. Narrow band imaging does not require contrast agent instillation, but has comparatively weaker data with recurrence at 12 mos in low risk patients decreased from 25% to 5%. However, this was an unplanned subgroup analysis and when all patients were considered, there was not a difference in recurrence. Dr. Liao next described a few cystoscopy-based improvements "not yet ready for prime time" including fluorescently-labelled CD47 antibody to molecularly target lesions not seen under white light. Also, he showed very nice images of 3d reconstructions of cystoscopic images with the potential to improve record keeping of cystoscopic findings.
For muscle invasive bladder cancer, he reviewed recent investigations into MRI- and PET-based diagnostics. mpMRI of primary tumor can correctly identify organ confinement a high percentage of the time, but whether this affects surgery or outcomes is not yet clear. FDG-based PET MRI has high sensitivity for LN mets, but still cannot replace PLND as a diagnostic tool. Overall, Dr. Liao seemed to think that FDG-based PET approaches could be improved with more specific molecular markers (although these have traditionally been difficult to identify in bladder cancer).
Overall, blue light cystoscopy should be implemented to help reduce recurrence rates, but its use in the post-bcg setting has not been validated yet. TURBT is still the gold standard for staging of the primary tumor, and FDG PET-based staging of the pelvic nodes still requires prospective validation prior to widespread clinical application.
Presented by: Joseph Liao, MD Stanford CA
Contributed by: Jed Ferguson, MD/PhD and Ashish Kamat, MD. MD Anderson Cancer Center, Department of Urology.
at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA