From the AGA Journals

Study models surveillance interval after ablation of Barrett’s esophagus



Surveillance endoscopy should be spaced at 1 and 3 years after complete eradication of low-grade intestinal metaplasia and at 3 months, 6 months, 1 year, and then annually in cases of high-grade dysplasia, researchers wrote in Gastroenterology.

This “much-attenuated schedule of surveillance endoscopy would provide protection from invasive adenocarcinoma,” wrote Cary C. Cotton, MD, of the department of medicine at the University of North Carolina at Chapel Hill, with his associates. Following this schedule could prevent unnecessary endoscopies while still detecting unresectable cancers at rates under 1 in 1,000 endoscopies, they added.

Barrett’s esophagus recurs in at least one in four cases after successful radiofrequency ablation, the researchers noted. Therefore, surveillance endoscopy is recommended after complete eradication of intestinal metaplasia, but only expert opinion informs the frequency of surveillance. This study modeled and validated rates of neoplastic recurrence by using data from the United States Radiofrequency Ablation Registry during 2004-2013 and from the United Kingdom National Halo Registry during 2007-2015.

In line with prior research, predictors of neoplastic recurrence included baseline histologic grade, age, sex, endoscopic mucosal resection, and baseline length of Barrett’s esophagus, the researchers said. The strongest predictor of recurrence was the most severe histologic grade identified before complete eradication of intestinal metaplasia. After controlling for covariates, a model based only on most-severe baseline histology predicted neoplastic recurrence with a C statistic of 0.892 (95% confidence interval, 0.86-0.92) in the United States Radiofrequency Ablation Registry.

Dysplasia recurred at similar rates regardless of whether patients had nondysplastic Barrett’s esophagus or indeterminate dysplasia. Recurrence rates also were similar between patients with high-grade dysplasia and patients with intramucosal carcinoma. Thus, the researchers identified three risk groups based on most-severe baseline histology: dysplastic Barrett’s esophagus or indefinite for dysplasia, low-grade dysplasia, and high-grade lesions or intramucosal adenocarcinoma.

The annual rate of any-grade neoplastic recurrence was 0.19% in the lowest-risk group, 1.98% in the intermediate-risk group, and 5.93% in the highest-risk group. “In the higher-risk groups, neoplastic recurrence occurred at a higher rate in the first year, but at a constant estimated rate thereafter,” the investigators wrote. Among 114 initial cases of neoplastic recurrence, 1.8% were esophageal adenocarcinoma and another 1.8% of patients developed esophageal adenocarcinoma within 6 months.

The researchers then modeled surveillance intervals by assuming a 2.9% rate of neoplastic recurrence per visit, which yielded a 0.1% rate of invasive adenocarcinoma. “This level of risk tolerance was chosen so that the risk of complications from surveillance endoscopy – approximately one in 1,000 in this patient population – would roughly approximate the risk of invasive carcinoma discovered at the exam,” they wrote. For patients at higher risk of endoscopic complications, they set the rate of neoplastic recurrence at 5.7%, which yielded a 0.2% rate of invasive cancer. “As would be expected, the higher the risk tolerance, the longer the period between endoscopic surveillance intervals.”

Based on the model, the researchers proposed surveillance intervals of 1 year, followed by 3 years, followed by more than 5 years for patients with completely eradicated low-grade dysplasia. For cases of high-grade dysplasia or carcinoma in situ, the proposed surveillance intervals were 3 months, 6 months, 1 year, and then annually. The model also performed well when applied to data from the United Kingdom National Halo Registry, the investigators said, noting that their approach was the first to directly establish an evidence base for surveillance practices in Barrett’s esophagus.

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