Purpose: Ta low-grade bladder tumors, accounting for 45% of new bladder cancer cases, have considerable risk of recurrence but low risk of progression. Traditionally, treatment is burdensome and costly. Office-based laser coagulation of Ta low-grade bladder tumors is efficient, tolerable, and safe; however, long-term outcomes need to be determined. The primary objective of this study was to determine whether in-office laser coagulation of recurrent Ta low-grade bladder tumor is noninferior to standard transurethral resection of bladder tumor (TUR-BT) regarding 12-month recurrence-free survival (RFS).
Materials and methods: Prospective, randomized, noninferiority clinical trial, performed in a hospital setting in Denmark between 2016 and 2022. Three hundred consecutive patients with recurrent Ta low-grade bladder tumor participated. Laser (photograph) coagulation of the bladder tumor (PC-BT) was performed with a 980 nm laser under local anesthesia in an office setting and compared with gold standard TUR-BT under general anesthesia. Primary outcome, 12-month RFS, was analyzed with noninferiority criterion of 15% absolute difference. Secondary outcomes included long-term RFS and stage progression.
Results: RFS at 12 months was 43.5% after PC-BT and 43.0% after TUR-BT; difference of -0.5% compared with PC-BT (one-sided 95% CI upper bound 12%), meeting noninferiority requirement. During extended follow-up (median 47.9 months), RFS was not significantly different between groups (P = .25) and only one case of stage progression was observed in each group.
Conclusions: Office-based laser photograph coagulation of bladder tumor is noninferior to TUR-BT regarding 12-month RFS and is a safe, efficient treatment for recurrent Ta low-grade bladder tumors.
Trial registration: ClinicalTrials.gov NCT02886026.
Keywords: 980 nm; NMIBC; bladder cancer; intermediate-risk; laser ablation; outpatient.