Immediate second resection versus restage transurethral resection of bladder tumor: A prospective randomized clinical trial (IMMERSE trial).

Background: The role of repeat transurethral resection of bladder tumor (TURBT) for the management of nonmuscle invasive bladder carcinoma is debated, especially when initial resections include detrusor muscle. This study compares immediate second resection (additional deep biopsies in the same session) with standard restage TURBT performed 2-6 weeks post-initial TURBT to determine adequacy in detrusor muscle sampling and compare the disease rate at restage TURBT in both groups.

Material And Methods: A randomized trial was conducted at a tertiary care hospital, including patients aged ≥18 years undergoing TURBT with complete primary tumor resection. Cases were randomized into two groups i.e., 'standard TURBT' (complete tumor resection with a deep biopsy) and "immediate second resection" (complete tumor resection, deep biopsy and additional deep biopsies). The primary endpoint was the presence of detrusor muscle in biopsy specimens, analyzed by a single pathologist. Secondary endpoints included perioperative complications, residual/ recurrent tumors, and factors affecting these recurrences.

Result: The study included 83 patients: 44 in the 'standard TURBT' group and 39 in the 'immediate second resection' group. The detrusor muscle was present in 66% of standard TURBT cases and 97% of immediate second resection cases, showing a statistically significant improvement (P = 0.000). Residual disease was found in 41% of restage TURBT patients in the standard group and 15% in the immediate second resection group, the majority being high-grade and T1 tumors (P = 0.028). There were no significant differences in tumor grade or perioperative complications between the groups. However, immediate second resection showed 18% higher detrusor muscle sampling rates than standard re-stage TURBT done at 2-6 weeks (P = 0.021).

Conclusion: Immediate second resection at the time of initial TURBT significantly improves detrusor muscle sampling rates and decreases residual tumors at restage. Despite higher muscle sampling, a considerable proportion of patients still exhibited residual or recurrent tumors in both groups, emphasizing the need for improved detection and biopsy techniques during primary TURBT.