Is low-intensity surveillance feasible for patients with high-risk NMIBC?

Low-intensity cystoscopic surveillance of patients with high-risk, non–muscle invasive bladder cancer (NMIBC) was associated with similar bladder cancer outcomes compared with American Urological Association (AUA)-recommended, high-intensity surveillance.

This is according to study findings presented at the 2020 American Urological Association Virtual Experience and published in PLOS One.^1,2

“Less intensive surveillance may be reasonable for high-risk NMIBC patients,” said Michael E. Rezaee, MD, MPH, the study’s lead author and a urology resident at Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire, in an interview with Urology Times®. “Our findings suggest that the optimal surveillance strategy for high-risk NMIBC needs to be determined.”

The AUA guideline, which Rezaee pointed out is primarily based on expert opinion, calls for patients with high-risk NMIBC to undergo cystoscopy every 3 to 4 months for 2 years after diagnosis. Not all patients are treated according to this guideline; some undergo lower-intensity surveillance, creating an opportunity to study the impact of such surveillance, explained Rezaee.

The study was comprised of 1542 VA patients diagnosed with high-risk NMIBC between 2005 and 2011, with follow-up taking place through 2014. The minority (n = 520) underwent low-intensity surveillance (1-5 cystoscopies over 2 years) and the majority (n = 1022) underwent high-intensity surveillance (≥ 6 cystoscopies over 2 years).

Risk of death did not differ significantly between groups

Investigators sought to assess if there was any difference in the risk of bladder cancer death between the 2 groups. They found that the risk of bladder cancer death did not differ significantly between the low-intensity (8.1%) and high-intensity (9.1%) surveillance groups at five years (P = 0.61).

Investigators also observed that high-risk patients who were surveilled less often underwent fewer transurethral resections (37 vs 99 per 100 person-years, P < 0.001).

“If they underwent fewer cystoscopies, they were taken to the operating room for a resection less often,” Rezaee said. “Fewer cystoscopies and resections did not translate into worse mortality risk in the low-intensity surveillance group.”

Florian R. Schroeck, MD, senior author of the paper and chief of urology at the White River Junction VA Medical Center in Vermont, is in the beginning stages of designing a randomized trial to determine if less frequent cystoscopy is safe in patients with high-risk NMIBC. The present study is limited by its retrospective design and unmeasured confounders, restricting the implications of its results, explained Rezaee.

A randomized trial may serve to demonstrate which patients need more surveillance and which need less.

“It is totally plausible to think that there are subgroups of high-risk patients who may need less surveillance while some patients may warrant even more surveillance,” he said. “We will be able to get more granular data from a prospective trial.

“We have been doing this [high-intensity surveillance] because it is habit, not because we know it’s the best thing to do,” said Rezaee. “There is no level I evidence to support the [AUA] guideline. We need to determine what the best surveillance strategy is.”

He pointed out that cystoscopies and subsequent resections are not benign procedures.

“The need for less frequent cystoscopy is also a wish of a lot of patients because it is not comfortable [to undergo],” he said.

References

1. Rezaee ME, Lynch KE, Li Z et al. The impact of low- versus high-intensity surveillance cystoscopy on surgical care and cancer outcomes in patients with high-risk non-muscle-invasive bladder cancer (NMIBC). Presented at: 2020 AUA Virtual Experience. Abstract PD50-08.

2. Rezaee ME, Lynch KE, Li Z et al. The impact of low- versus high-intensity surveillance cystoscopy on surgical care and cancer outcomes in patients with high-risk non-muscle-invasive bladder cancer (NMIBC). PLoS One 15(3): e0230417. https://doi.org/10.1371/journal.pone.0230417.