Prospective multicenter trial of the cryoballoon ablation system for superficial esophageal squamous cell carcinoma on post-endoscopic resection scars: a CRYO-SCAR study (EPOC1902).

ABSTRACT

BACKGROUND AND AIMS: Endoscopic resection is a minimally invasive treatment for superficial esophageal squamous cell carcinoma (SESCC). Post-endoscopic resection scars complicate en-bloc resection, even with advanced techniques, such as endoscopic submucosal dissection. The cryoballoon ablation system (CBAS) effectively manages Barrett's esophagus but has limited evidence in SESCC treatment, particularly on post-endoscopic resection scars. This study aimed to evaluate the efficacy and safety of the CBAS for treating SESCC on post-endoscopic resection scars. METHODS: This prospective study was conducted at 2 tertiary referral centers in Japan in patients endoscopically diagnosed with T1a SESCC on the post-endoscopic resection scar. Focal CBAS was used for cryoablation, with specific criteria for lesion selection and treatment method. The primary endpoint was the rate of local complete response (L-CR) of the primary lesion 48 weeks after the first cryoablation as evaluated by an independent central evaluation committee. RESULTS: From October 2020 to October 2021, 15 patients with 17 lesions underwent cryoablation, with 2 requiring repeat cryoablation. The L-CR rate for primary and all lesions evaluated by the central evaluation committee was 100%. The endoscopist's evaluation was consistent with these results. The median procedure time was 9 minutes. Eight patients experienced no pain, and the highest pain score reported on a numeric rating scale from 1 to 10 was 3. The technical success rate was 94.7% (18/19). Throughout the median follow-up period of 14.3 months, recurrences, deaths, or severe treatment-related adverse events were not reported. CONCLUSIONS: CBAS is a potentially safe and effective approach for SESCC on post-endoscopic resection scars and represents an encouraging alternative to traditional endoscopic treatments. (Clinical trial registration numbers NCT03097666 and jRCT1080225331.).