Ongoing efforts aim at overcoming the challenges of conventional transurethral resection of bladder tumor (TURBT) such as the high recurrence rate, difficulties in the pathologic interpretation of the specimen and TURBT related complications. We assessed the feasibility, safety and early efficacy of Thulium-fiber en bloc resection of bladder tumor (Tm-fiber-ERBT) and compared it to conventional TURBT.
This prospective non-randomized study included 129 patients with non-muscle-invasive bladder cancer (NMIBC) divided into 58 who underwent conventional TURBT and 71 who underwent Tm-fiber-ERBT. The later was performed using the FiberLaser U1 (NTO IRE-Polus, Russia) through a 26 FR resectoscope. All patients received a single dose of intravesical MMC chemotherapy within the first two hours after surgery. Adjuvant intravesical MMC was given weekly for eight weeks in patients with intermediate-risk disease. The primary endpoint was relapse free survival (RFS), and secondary endpoints included rate of detrusor muscle and complications.
RFS at 3 and 6 months for conventional TURBT were 84.5% and 67.2% compared to 97.2% and 91.6 % for Tm-fiber-ERBT (p=0.011 and p<0.001, respectively). Detrusor muscle was present in 58.6% of cases treated with conventional TURBT vs 91.6% for Tm-fiber-ERBT treated cases (p<0.001). Patients underwent re-TURB in all cases missing detrusor in the specimen. On multivariable analysis, only type of surgery (OR 6.10; CI 95% 1.57-23.79, p=0.009) and presence muscle in the specimen (OR 4.63; CI 95% 1.11-19.36 p=0.036) were associated with RFS; whereas, patient sex, age, MMC installation, tumor location, concomitant CIS, tumor stage and grade were not. Obturator nerve reflex and bleeding were observed in 17.2% and 10.3% of patients treated with conventional TURBT, respectively, compared to none in patients treated with Tm-fiber-ERBT. Limitations of the current study include its small size, single center, and non–randomized nature.
Tm-fiber-ERBT seems to be a safe and efficacious diagnostic and therapeutic approach in patients presenting with NMIBC. Tm-fiber-ERBT had less adverse events, was more likely to secure detrusor muscle in the specimen and resulted in better RFS rates than conventional TURBT. Based on these promising data, we have started a prospective randomized clinical trial comparing en bloc TURB with conventional TURB (ClinicalTrials.gov NCT03718754).