Can bladder MRI avoid systematic second TURBT for patients with high-risk NMIBC?

BACKGROUND AND OBJECTIVES: Repeat transurethral resection of bladder tumor (2nd -TURBT) is recommended for high-risk non-muscle invasive bladder cancer (HR-NMIBC) to reduce the risk of understaging and residual tumors. Despite its proven benefits, 2nd -TURBT remains an invasive and costly procedure. This study aimed to evaluate if bladder MRI, performed before initial TURBT (i-TURBT), could be in selected patient, a non-invasive alternative to 2nd -TURBT. METHODS: Data from 34 single-center patients who had MRI performed prior to i-TURBT and underwent 2nd -TURBT for HR-NMIBC between March 2020 and July 2024 were retrospectively collected. RESULTS: MpMRI demonstrated high accuracy in detecting muscle-invasive bladder cancer, with sensitivity, specificity, positive predictive value, and negative predictive value of 100% (95% CI 0.61-1), 96% (95% CI 0.82–0.99), 86% (95% CI 0.49–0.97), and 100% (95% CI 0.87-1), respectively. Among patients with mpMRI findings suggestive of NMIBC (n = 27), the residual tumor rate was 12% (n = 3). No residual tumor was found on 2nd-TURBT in patients with pTa tumor (n = 6) on i-TURBT and VIRADS ≤ 3, neither with pT1 tumor and detrusor muscle sampled on i-TURBT (n = 28), with unifocal VIRADS ≤ 3. CONCLUSION: Bladder MRI appears to be a valuable tool in HR-NMIBC management and could avoid 2nd -TURBT in selected patients, with a unifocal VIRADS ≤ 3 lesion and detrusor muscle sampled in i-TURBT.