Bladder tumor ablation with 980-nm and 980-/1470-nm diode lasers: a retrospective study

This study evaluated the safety and feasibility of ablation of both non-muscle invasive and muscle invasive bladder tumors using single- and dual-wavelength diode lasers (980 nm and 980/1470 nm). We retrospectively examined 151 patients with bladder tumors of any type from 2009 to 2021 who underwent V-LABT (visual laser ablation of bladder tumor) with both single- and dual-wavelength diode lasers at Shalamar Hospital Lahore, Pakistan. All procedures were performed by the same surgeon. Shalamar Medical and Dental College review board approved this retrospective cohort study (IRB No. -623-2023). The collected clinical data were consolidated into a single group, encompassing various variables such as the patients’ age, tumor size, number of tumors, tumor location, tumor grade, ablation duration, postoperative catheterization time, bladder discomfort, obturator nerve reflex, intraoperative and postoperative complications, and recurrence of tumors at the ablation sites. The patients were monitored for a minimum of 12 months to observe recurrence at the ablation sites through cystoscopy performed postoperatively every three months. The data were analyzed using Chi-square test, and p value < 0.05 was considered significant. The average age of the 151 patients was found to be 64.72 ± 13.85 years. The size of the tumors was 4.88 ± 2.16 cm, with 48/151 (31.7%) patients having tumors larger than 3 cm. Among the cases studied, 117/151 (77.4%) patients had a single tumor, while the remaining patients had multiple tumors ranging in size from 5 to 7 cm in aggregate. Ablation took 1.57 ± 0.73 h to complete on average. None of the patients required a conversion to TURBT in 151 patients. No obturator reflexes or bladder perforations were observed in any case. Postoperatively, histopathology results showed 53/151 (35%) and 92/151 (60.9%) high- and low-grade tumors. The average catheterization duration was 6.58 ± 1.47 days. Tumors located on difficult sites, such as the anterior wall, lateral wall, and bladder neck, were ablated with ease. There was no recurrence seen on previously tumor ablated sites till 12-month follow-up. Ablation of bladder tumors of any type using single- or dual-wavelength diode laser (980 nm and 980/1470 nm) is safe and feasible. These lasers possess the capability to effectively ablate/coagulate bladder tumors in challenging anatomical locations including diverticular tumors with minimal difficulty.