Aims:
Cryoballoon ablation is endoscopic cryotherapy for Barrett's esophagus (BE), which offers potential advantages over heat-based ablation. Focal CBA has been promising for limited BE, whereas the novel 90 °-swipe CBA (CbSAS90) ablates larger areas (90 ° over 3 cm) in a single-step. The controller software allows for dose adjustment (rate at which the diffuser traverses the 3 cm long catheter axis while emitting cryogen). CbSAS90 has been feasible and safe in animal and pre-esophagectomy studies. This is the first clinical study to assess feasibility, safety and efficacy of CbSAS90 for dysplastic BE.
Methods:
Patients with flat BE (≤3 cm) and low/high-grade dysplasia (LGD/HGD) or residual BE after endoscopic resection (ER) were enrolled. We started dose-finding with semi-circumferential treatment at dose 1 (0.8 mm/s). This was escalated with 0.1 mm/s (N = 6 per dose) until the dose resulted in BE regression≥80% without dose-related SAEs (DR-SAEs). This effective dose (ED) was confirmed with circumferential treatment (N = 12). DR-SAEs included severe pain ≥7days or stenosis. Pain (VAS 0 – 10) and dysphagia (0 – 4) were evaluated at days 0,1,7&30. Outcomes were technical success, DR-SAEs and efficacy (BE regression at 8-weeks follow-up).
Results:
Twenty-five patients were included (median Prague C0M3, 20% prior ER). Technical success was 92% (23/25pts). Device malfunctions occurred in 8%, all resolved with replacement. BE regression was 78% (IQR 68 – 86) for dose 1 (0.8 mm/s) and 85% (IQR 75 – 95) for dose 2 (0.7 mm/s), which was in turn defined as ED. Circumferential treatment with the ED resulted in 94% (IQR 89 – 97) BE regression. However, 2 patients (17%) developed a stenosis after circumferential treatment (1&3 dilatations). Median pain scores were 3 (IQR 1 – 5), 1 (0 – 2), 0 (0 – 0) and 0 (0 – 0) at days 0,1,7&30 respectively. Median dysphagia scores were 0 at all days.
Conclusions:
CbSAS90 is feasible and a promising tool for ablating larger areas of dysplastic BE. However, because of concerns with respect to strictures, the dose that optimally balances efficacy and safety needs further evaluation in larger studies with direct circumferential treatment.
