Blue light cystoscopy shows utility for post-BCG bladder cancer surveillance

Blue light cystoscopy identified patients with bladder cancer recurrence post-BCG that would have been missed with standard white light cystoscopy alone.

Blue light cystoscopy (BLC) with hexaminolevulinate hydrochloride (Cysview) showed promising clinical utility as a surveillance tool in patients with bladder cancer who recently received BCG, according to findings presented during the 2020 Society of Urologic Oncology Annual Meeting.1

Specifically, BLC identified patients with bladder cancer recurrence post-BCG that would have been missed with standard white light cystoscopy (WLC) alone.

“Providers should consider using BLC for surveillance of high-risk NMIBC patients undergoing BCG as it could change clinical management by identifying patients who are BCG unresponsive and eligible for alternative therapy and clinical trials,” first study author Meera Chappidi, MD, UC San Francisco, and coauthors wrote.

Research from previous trials showed enhanced detection of initial and recurrent cancers in patients with non-muscle invasive bladder cancer when using BLC compared with WLC. The value of BLC surveillance in patients receiving BCG, however, has yet to be determined. “Identifying early recurrences in patients receiving BCG can result in them being enrolled into clinical trials for BCG unresponsive disease,” wrote Chappidi et al.

Data for the analysis were obtained from the Cysview registry, a prospectively collected, multi-institutional database. The researchers identified 258 patients treated between 2014 and 2019 who had received BCG treatment within 2010 days before BLC. Six patients had received multiple cystoscopy procedures. Patients were excluded from the study if pathology data were not available and if data were not available regarding whether lesions were visible on WLC, BLC, or both.

Overall, 120 (46.5%) patients had recurrence and 138 (53.5%) did not. Among the patients without recurrence, the median age was 69 years, 86.2% were white, and 79% were male. The time since BCG was <6 weeks (7.2%), 6-12 weeks (38.4%), or >12 weeks (54.3%).

In the group of 120 patient who had recurrence, the median age was 72.9 years, 84.2% were white, and 88.3% were male. The time since BCG was <6 weeks (6.7%), 6-12 weeks (32.5%), or >12 weeks (60.8%). Recurrence stages included HGTa (14.2%), CIS (30%), LGTa + CIS (0.8%), HGTa+ CIS (17.5%), T1 (16.7%), T1 + CIS (6.7%), ≥T2 (7.5%), and ≥T2 + CIS (1.7%).

The researchers determined that 16 (13%) of the 120 recurrences would not have been detected if WLC alone had been used. These 16 recurrences had a normal WLC, but had high-grade recurrence identified by BLC. Among these 16 patients, 14 (88%) had CIS. The false-positive biopsy rate was 4% (11 of 258 patients) for BLC. Twenty-seven (10.5%) of the 258 patients in the overall population received intravesical chemotherapy.

“Future research is warranted to better clarify how BLC should be used both for entry into clinical trials and for surveillance while on trials, in order to maintain consistency of patient outcomes within a given trial and to allow for comparison of response rates across different trials,” concluded Chappidi et al.

Reference

1. Chappidi MR, Yang H, Meng MV, et al. Utility of surveillance blue light cystoscopy for bladder cancer after BCG: implications for clinical trial recruitment and study analysis. 2020 Society of Urologic Oncology Annual Meeting (virtual). December 3-5, 2020. Poster 28.