Predictive factors of the absence of residual disease at repeated transurethral resection of the bladder. Is there a possibility to avoid it in well-selected patients?

PURPOSE:To evaluate the predictive factors of pT0 at repeated transurethral resection of the bladder (re-TURB) in pT1 high-grade (HG) nonmuscle invasive bladder cancer in order to explore the possibility to avoid it in well-selected patients. METHODS:This multicenter retrospective study included patients with pT1HG nonmuscle invasive bladder cancer from 4 different centers who underwent a complete TURB. Re-TURB was defined as a second resection which involved the site of the first TURB performed within 2-6 weeks from the previous resection. A multivariable logistic-regression model was performed to evaluate the predictors of pT0 at re-TURB. A nomogram was built to calculate the probability of obtaining a negative histology at re-TURB. The performance of the nomogram and its net benefit were tested with the decision curve analysis. RESULTS:Overall, 321 patients were included in the study. On multivariable logistic regression, detrusor muscle in the specimen (HR 1.99, P = 0.02), concomitant carcinoma in situ (HR 0.29, P = 0.005) and resection performed with en-bloc technique (HR 7.71, P = 0.01) were independent predictors of pT0 at re-TURB. Decision curve analysis showed a net benefit for the nomogram for each probability over 0.35 compared to the strategy to perform a re-TURB in all pT1HG tumors. CONCLUSIONS:The presence of detrusor muscle in TURB specimen, the absence of concomitant carcinoma in situ and the en-bloc resection were able to predict a negative histology at re-TURB, opening the door to the possibility to avoid it in an extremely well-selected cohort of patients. External validations and prospective studies are urgently needed.