Transurethral en bloc resection with monopolar current for non-muscle invasive bladder cancer based on TNM system

BACKGROUND: To evaluate the surgical safety and quality of transurethral en bloc resection with monopolar current for non-muscle invasive bladder cancer (NMIBC) based on the tumour, node, metastasis (TNM) classification system, and report the midterm oncological outcome. METHODS: From October 2015 to June 2017, en bloc resection of bladder tumor (ERBT) and transurethral resection of bladder tumor (TURBT) were performed in 96 and 87 patients clinically diagnosed with NMIBC in the prospective case-control trial, respectively. Operative details, intraoperative and postoperative complications regarded as safety outcomes were documented. The quality of ERBT was judged by the histopathological examination of tumor specimens from initial resection and second TURBT, random bladder biopsy and follow-up recurrence rate. RESULTS: Operative time, obturator nerve reflex, irrigation and catheterization time were similar in the two groups. Bladder perforation was occurred in 2 patients during ERBT and 9 patients during TURBT (2/96 vs. 9/87, P=0.019). Compared with TURBT group, the ratio of detrusor muscle (DM) identified in pathologic T1 tumor specimens was higher (P=0.024), but lower in pathologic Ta tumor specimens in ERBT group (P<0.001). The residual tumor identified in ERBT group was lower than that in TURBT group during second TURBT (2/28 vs. 10/32, P=0.020). The recurrence-free survival rate did not differ significantly between the two groups after 24 months follow-up. CONCLUSIONS: ERBT based on TNM system is a safe and feasible technique to treat patients with NMIBC. Besides, ERBT may reduce the proportion of bladder perforation and residual tumor during initial resection.