Adjuvant Endoscopic Balloon Cryoablation Demonstrates Safety, Efficacy in Non–Muscle-Invasive Bladder Cancer

According to results of a phase 2 trial, endoscopic balloon cryoablation was found to be a safe and effective therapy, following transurethral resection, for patients with non–muscle-invasive bladder cancer (NMIBC).

Cryotherapy is a known percutaneous ablative therapy for patients with solid tumors and is currently being explored for bladder tumors. This is the first randomized trial to evaluate “a novel device using liquid nitrogen for endoscopic cryotherapy of bladder cancer,” as lead author Chenyang Xu, MD, Huashan Hospital, Shanghai, China, and colleagues explained.

This multicenter, parallel-controlled trial enrolled 205 patients with NMIBC between November 2017 and September 2020. Patients were randomized on a 1:1 basis to receive either endoscopic balloon cryoablation, or a single installation of pirarubicin. In the endoscopic balloon cryoablation group, cryoablation was applied immediately following transurethral resection, with 2 or 3 cycles of cryotherapy delivered to fully cover the lesion. Residual tumor was evaluated at 4 to 6 weeks after primary treatment via either repeat transurethral resection or tissue biopsy. The primary end point was local control rate. The secondary end points included tumor upgrading/upstaging, catheter indwelling duration, and safety.

At the data cutoff date, the median follow-up duration was 31 months, and 163 patients had completed all required interventions (endoscopic balloon cryoablation, n = 82; single installation, n = 81). Per-protocol, the endoscopic balloon cryoablation group had a local control rate of 91.5% compared with 76.5% in the single installation group (risk difference: 15%; 95% confidence interval [CI], 0.03 to 0.27; P < .001). With these control rates, endoscopic balloon cryoablation met the criteria for noninferiority. In the modified intention-to-treat analysis, the results were similar.

In the single installation group, there were 5 patients with tumor upgrading/upstaging. The catheter indwelling durations were similar in both groups (5.1 days for the endoscopic balloon cryoablation group vs 5.2 days for the single installation group; P = .76), as were the adverse event rates (3% vs 3.9%; P = .52). Study authors also noted that patients who were treated with endoscopic balloon cryoablation had better recurrence-free survival and progression-free survival.

“Results report that [endoscopic balloon cryoablation] is not inferior to a single installation of intravesical chemotherapy in eliminating residual bladder tumor,” Dr Xu et al, concluded.

Source:

Xu C, Jiang S, Zou L, et al. Endoscopic balloon cryoablation plus transurethral resection for bladder cancer: A phase 2, multicenter, randomized, controlled trial. Cancer. Published online December 7, 2022. doi:10.1002/cncr.34563

Jiang H. A multi-center, randomized, parallel controlled study of applying transurethral resection of bladder tumor with adjuvant cryoablation to treat bladder cancer. ClinicalTrials.gov identified: NCT02760953. Updated October 19, 2017. Accessed December 14, 2022. https://clinicaltrials.gov/ct2/show/NCT02760953