Similar to radiofrequency ablation, cryoballoon ablation (CBA) is a durable approach that can eradicate Barrett’s esophagus (BE) in treatment-naive patients with dysplastic BE, according to a single-center cohort study.
Endoscopic mucosal resection (EMR), radiofrequency ablation (RFA), and cryotherapy are established techniques used in endoscopic eradication therapy of BE, wrote study authors led by Mohamad Dbouk, MD, of Johns Hopkins Medical Institutions in Baltimore in Techniques and Innovations in Gastrointestinal Endoscopy. Unlike RFA which uses heat to induce tissue necrosis and reepithelialization of normal tissue, cryotherapy applies extreme cold in the treatment of BE. While cryotherapy as an endoscopic ablative technique has been studied over the past decade as an alternative treatment modality, Dr. Dbouk and researchers noted that long-term data on durability of and outcomes with this approach are lacking.
To gauge the durability of CBA for dysplastic BE, the researchers examined outcomes of 59 consecutive patients with BE and confirmed low-grade dysplasia (n = 22), high-grade dysplasia (n = 33), or intramucosal cancer (n = 4), all of whom were treated with CBA for the purposes of BE eradication. The single-center cohort comprised only treatment-naive patients who had a mean age of 66.8 (91.5% male). In the overall cohort, the mean length of the BE was 5 cm, although 23.7% of patients had BE ≥8 cm in length.
Following confirmation of dysplastic BE in biopsies and/or EMR specimens at baseline, patients underwent CBA applied to the gastric cardia as well as all visible BE with the cryoballoon focal ablation system and focal or pear-shaped cryoballoon. The investigators performed surveillance esophagogastroduodenoscopy (EGD) to assess the CBA response. Patients with high-grade dysplasia underwent EGD and biopsy every 3 months for the first year after completing CBA, every 6 months for the second year, and once per year thereafter. However, those with biopsies at baseline that showed low-grade dysplasia (LGD) underwent EGD and biopsy every 6 months during the first year after CBA and annually thereafter. Retreatment with ablation was allowed if recurrent dysplasia or intestinal metaplasia was found.
The study’s primary endpoints included short-term efficacy – defined as the rate of complete eradication of dysplasia (CE-D) and intestinal metaplasia (CE-IM) at 1-year follow-up – and durability – characterized by the proportion of patients with CE-D and CE-IM within 18 months and maintained at 2- and 3-year follow-up.
The median follow-up period for the patient cohort was 54.3 months. Approximately 95% of the 56 patients who were evaluable at 1 year achieved CE-D, while 75% achieved CE-IM. In an analysis that stratified patients by their baseline dysplasia grade, the rates of CE-D were each 96% in the LGD and HGD groups. At 1 year, the median number of CBA sessions used to achieve CE-IM was 3.
Throughout treatment and the follow-up period, none of the patients progressed beyond their dysplasia grade at baseline or developed esophageal cancer. All patients had maintained CE-D for years 2, 3, and 4. In addition, 98% of patients had CE-IM at 2 years, 98% had CE-IM at 3 years, and 97% of patients had CE-IM at 4 years. After stratification of patients by baseline grade of dysplasia, the researchers found no significant difference between groups in the rates of CE-D and CE-IM at each follow-up year.
In 48 patients who initially achieved CE-IM, 14.6% developed recurrent intestinal metaplasia (IM), including six in the esophagus and one in the GEJ, after a median of 20.7 months. Approximately 57% of patients who developed recurrent IM had baseline LGD, while 43% had HGD at baseline. The length of BE was not significantly associated with the risk of IM recurrence, according to a Cox proportional hazard analysis (hazard ratio, 1.02; 95% confidence interval, 0.86-1.2; P = .8).
Approximately 8.5% of patients had post-CBA strictures that required dilation during the study period. According to bivariate analysis, individuals with a BE length of ≥8 cm were significantly more likely to develop strictures, compared with patients without ultra-long BE (28.6% vs. 2.2%, respectively; P = .009). Strictures occurred during the first 4 months after the initial CBA. The median period from the first CBA treatment to stricture detection on follow-up EGD was 2 months. Around 1.7% of patients experienced postprocedural bleeding that required clipping for closure. These patients were on clopidogrel for atrial fibrillation during the first year of active treatment.
Limitations of the study included the small sample size as well as the inclusion of patients from a single center, which the researchers suggest may limit the generalizability of the results.
“More research is needed to confirm the long-term durability of CBA,” the authors concluded. “Randomized controlled trials comparing CBA with RFA are needed to assess the role of CBA as a first-line and rescue EET.”
Several of the researchers reported conflicts of interest with industry. The study received no industry funding.
