Predictive Factors for Residual Cancer in Second Transurethral Resection for Non-muscle-invasive Bladder Cancer.

Abstract

The significance of second transurethral resection (TUR), and identification of predictive factors for residual cancer remain unrevealed. This study aimed to find residual cancer and up-staging rates, as well as predictive factors for residual cancer, in patients who undergo second TUR for non-muscle-invasive bladder cancer (NMIBC). Patients who underwent second TURs for NMIBC between 2015 and 2017, were included in the study and their clinicopathological characteristics were analyzed for predictors of residual cancer. Among 143 Japanese patients whose tumors were initially diagnosed as high-risk NMIBC, residual cancers detected at second TURs were, Tis: n=22 (15.4%), Ta: n=15 (10.5%) and T1: n=29 (20.3%). No patients showed up-staging from NMIBC to MIBC. The presence of carcinoma-in situ at initial TUR was an independent risk factor for any residual cancer (Tis, Ta and T1), non-flat residual cancer (Ta and T1), and flat residual cancer (Tis). The presence of carcinoma-in situ is suggested to be an independent predictor of residual cancer. This may help guide decisions to perform second TUR.