1712 Detection of Sub-Surface High-Grade Dysplasia Following Radiofrequency Ablation (RFA) of Barrett’s Esophagus

Abstract

INTRODUCTION: Barrett's esophagus (BE) occurs when intestinal epithelium replaces squamous epithelium normally lining the distal esophagus. BE is associated with an increased risk of esophageal adenocarcinoma (EAC). While traditionally associated with Caucasian males, prevalence of BE and EAC in Asian populations is projected to rise, associated with increasing prevalence of gastroesophageal reflux disease (GERD), which is associated with obesity and hiatal hernia. Radiofrequency ablation (RFA) is an endoscopic treatment modality shown to be safe and effective in inducing reversion to squamous epithelium, with a treatment depth of 500-1000 microns. We present a case of BE with high-grade dysplasia identified on random forceps biopsy after RFA for BE with low grade dysplasia, after which significant sub-surface disease was detected by volumetric laser endomicroscopy (VLE). CASE DESCRIPTION/METHODS: A 72 yo Chinese male was diagnosed with short-segment BE containing low grade dysplasia, and was treated with 2 sessions of focal RFA 5 months apart. He was lost to follow up and re-established care two years later. At presentation, the patient denied any heartburn, dysphagia or weight loss. Surveillance endoscopy with white light and narrow band imaging (Figure 1) revealed short tongues of salmon-colored mucosa suspicious for residual BE. Forceps biopsy confirmed BE with high grade dysplasia at the 12:00 position. Repeat endoscopy using VLE demonstrated suspicious-appearing glands, primarily sub-surface, which were laser marked and resected with band ligation and snare instead of forceps biopsy (Figure 2). Pathology results confirmed high-grade dysplasia within BE (Figure 3). Due to the presence of dysplasia deeper into the epithelium, in the setting of prior RFA, the patient was referred for liquid nitrogen spray cryotherapy. DISCUSSION: Residual or recurrent BE following RFA is a relatively common finding, but it is uncommon to see disease with a higher dysplasia grade than what was found pre-treatment. In this case, the use of VLE to evaluate these findings identified deeper disease that may not have been amenable to initial RFA treatment, with the lesion becoming “buried” after incomplete ablation. VLE, which visualizes the esophageal wall to a depth of 3 mm, should be considered as part of the evaluation of residual BE, especially when dysplasia is present. Its use may improve patient outcomes by leading to an alternate approach to both tissue sampling and further treatment selection.