Betty Wang, MD, BS, University of Alberta, and colleagues reported significant inter-site variation—independent of differences in tumor factors—in recurrence of non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of bladder tumor (TRUBT) in the RESECT study.
Their study won the best poster for the Bladder Cancer: Non-Invasive session at the American Urological Association 2023 meeting.
RESECT is an international, multi-center, observational study that sought to determine if audit and feedback can improve the quality of TURBT surgery and reduce early recurrence rates in NMIBC. A mixed effects logistic regression model with tumor size, number, grade, and stage as fixed effects, as well as site as a random effect, was fitted. Cases with first, presumed NMIBC undergoing TURBT were included, while cases in which first check follow-up had not been completed were excluded.
Researchers noted that local and national approvals or ethical exemptions were obtained prior to study initiation at participating sites. After such exemptions, a total of 186 international sites contributing 4597 cases were included.
Dr. Wang and colleagues reported the median recurrence rate per site was 12% for low-grade tumors and 27% for high-grade tumors. After controlling for tumor size, number, stage, and grade, they found significant residual variation that was attributable to site (P<.0001).
Furthermore, they added that adjustment for sites improved the regression model from an area under the receiver operating characteristic curve of 0.66 to 0.74.
“There is significant variation in the early recurrence rate of NMIBC after TURBT surgery between sites that could not be explained by currently understood tumor features,” Dr. Wang and colleagues concluded, acknowledging that this variation may be related to site-specific surgical technique or perioperative practice.
“Further investigation is warranted to understand the influence of these factors,” they added.