Implications of Guideline-based, Risk-stratified Restaging Transurethral Resection of High-grade Ta Urothelial Carcinoma on Bacillus Calmette-Guérin Therapy Outcomes

Background Guideline indications for restaging transurethral resection (reTUR) for high-grade (HG) Ta bladder tumors vary due to a paucity of data. Objective To investigate guideline-based, risk-adapted approaches to reTUR for HG Ta lesions. Design, setting, and participants An institutional review of HG Ta patients who received adequate bacillus Calmette-Guerin (BCG) from 2000 to 2019 was conducted. Outcome measurements and statistical analysis Guideline criteria for reTUR were used to stratify patients. Kaplan-Meier product limits estimated survival. Cox regression and log-rank tests identified association of variables with survival. Results and limitations Of the 209 patients with HG Ta bladder cancer, 104 (50%) underwent reTUR, which identified residual disease in 39 patients (38%). Only one patient (1%) was upstaged to pT1 on reTUR. In all unstratified HG Ta patients, reTUR was associated with improved progression-free survival (p = 0.050) and recurrence-free survival (RFS; p = 0.003). The 5-yr RFS for patients who underwent versus those who did not undergo reTUR based on AUA guidelines was 73% (95% confidence interval 63–81%) versus 52% (40–62%), and for those who underwent versus those who did not undergo reTUR based on EAU guidelines was 76% (61–86%) versus 22% (4–49%). In 45 patients meeting both AUA high-risk criteria (large, multifocal tumors) and EAU criteria (lack of detrusor muscle) for reTUR, lack of restaging was associated with over a two-fold increase in recurrence (67% vs 15%, p = 0.002) and progression (25% vs 6%, p = 0.109). Data were limited by selection bias unaccounted for in selecting candidates for reTUR. Conclusions Restaging TUR in all HG Ta patients, regardless of risk stratification, was associated with improved outcomes. The benefit of reTUR was most notable in high-risk patients without muscle in the index specimen, consistent with components of both AUA and EAU guidelines. These data support a non–risk-adapted approach to reTUR for all HG Ta lesions. Patient summary Restaging bladder tumor resection improves outcomes in patients with high-grade Ta tumors treated with bacillus Calmette-Guerin (BCG).