MP08-10: Global Variation in Early Recurrence After Transurethral Resection of Bladder Tumor in the RESECT study (NCT05154084): There is Significant Inter-site Variation that is Independent of Differences in Tumour Factors
Introduction: To determine if there is significant variation in early recurrence (first check cystoscopy) after transurethral resection of bladder tumor (TURBT) surgery between sites taking part in the RESECT study (NCT05154084) after accounting for tumour characteristics. Methods: RESECT is an international, multi-centre, observational study. A mixed effects logistic regression model with tumour size, tumour number, tumour grade, tumour stage as fixed effects and site as a random effect was fitted. Cases with first, presumed non-muscle invasive bladder cancer (NMIBC) undergoing TURBT were included. Cases were excluded if first check follow up had not been completed. Sites were excluded if they did not have at least 10 cases with first check follow up. Local and/or national approvals or ethical exemptions were obtained prior to commencing the study at participating sites. Results: After exclusions, 186 sites (UK: 80; Europe: 59; North America: 18; Asia: 17; Africa 7; South America: 3; Oceania: 2), contributing a total 4597 cases (average 25 cases) were included. Median recurrence rate per site was 12% (IQR 0-22) for low grade tumours and 27% (IQR 13-42) for high grade tumours (figure 1). After controlling for tumour size, number, stage and grade (all significantly and independently associated with early recurrence) (Table 1) there was significant residual variation attributable to site (p < 0.0001, intra-class correlation, 0.1). Adjustment for sites improved the regression model from an area under the receiver operating characteristic curve of 0.66 to 0.74. Conclusions: There is significant variation in the early recurrence rate of NMIBC after TURBT surgery between sites that could not be explained by currently understood tumour features. This may be related to site-specific surgical technique or perioperative practice. Further investigation is warranted to understand the influence of these factors. SOURCE OF Funding: Rosetrees Trust, The Urology Foundation, Action Bladder Cancer UK, BJUI International, Karl Storz, Photocure, Medac Pharma
