"En Bloc" Resection of Nonmuscle Invasive Bladder Cancer: A Prospective Single-center Study.

<bold>Objective: </bold>To describe our "en bloc" technique for nonmuscle invasive bladder cancer (NMIBC), assess the quality of resection, and report the midterm oncological outcome.<bold>Materials and Methods: </bold>This is an observational prospective longitudinal study, from June 2010 to February 2014, enrolling patients with clinically NMIBC, having tumors of ≤3 cm and ≤4 lesions who underwent electrical en bloc bladder resection. The primary study end point was recurrence-free survival. Secondary outcomes were feasibility, safety, the presence of detrusor muscle, and the recurrence rate at the first follow-up cystoscopy (3 months). Statistical analysis was complemented with multivariable analysis.<bold>Results: </bold>Of 87 enrolled patients, 2 showed a nonurothelial carcinoma and 11 showed muscle invasive bladder carcinoma at the definitive pathology. The study cohort consisted of 74 transitional cell carcinoma NMIBC cases, mean age 71 years ± 8, presenting with a mean tumor diameter of 1.98 ± 0.59 cm and a median number of resected tumors per patients of 1 (range 1-4). The 2-year recurrence-free survival was 85.59%. All the en bloc resection of bladder tumor samples showed the presence of detrusor muscle and the recurrence rate at the first follow-up cystoscopy (3 months) was 5.4% (4/74). An extraperitoneal bladder perforation occurred in only one patient. At multivariable analysis, only gender and the presence of carcinoma in situ were independent predictors of recurrence. The midterm follow-up and the absence of a control group are the main limitations.<bold>Conclusion: </bold>Our findings confirmed the feasibility and safety of en bloc resection of bladder tumor, with a recurrence-free survival of 85% after 2 years. [ABSTRACT FROM AUTHOR]