The direct anti-cancer effect of a single instillation of epirubicin after transurethral resection of bladder tumor for non-muscle-invasive bladder cancer

Purpose: To evaluate the direct anti-cancer effect of a single instillation of epirubicin (SIE) after transurethral resection of bladder tumor (TURBT) for non-muscle-invasive bladder cancer (NMIBC) by analysis of immediate urine cytology (IUC). Materials and Methods: We reviewed the records of 158 patients who had IUC after TURBT for NMIBC. Fifty-six patients were treated with SIE after TURBT and 102 patients were not treated with SIE. The direct anti-cancer effect of SIE was compared in the two groups according to the result of IUC. The relationship between SIE and IUC in NMIBC was analyzed by use of multivariate Cox proportional hazards regression models. Results: The IUC-positive rate was 33.9% in the SIE group and 42.1% in the non-SIE group (p=0.005). The IUC-positive rate was lower in the SIE group than in the non-SIE group for each factor, including tumor stage, tumor grade, tumor size, tumor multiplicity, and preoperative urine cytology. Multivariate Cox proportional hazards regression analysis revealed that SIE was significantly associated with a negative IUC result in patients with NMIBC (HR, 0.163) (p<0.001). Conclusions: These results indicate the direct anti-cancer effect of SIE in patients who undergo TURBT for NMIBC.