The Prevalence, Risk Factors and Optimal Biopsy Protocol of BE

Barrett's esophagus (BE) is premalignant lesion for esophageal adenocarcinoma (EAC) and defined as the distal esophageal squamous epithelium replaced by columnar epithelium with histologic confirmation of intestinal metaplasia (IM). The accurate prevalence of BE is difficult to assess because part of people with BE are asymptomatic. However, the prevalence of gastroesophageal reflux disease (GERD) which is the main factor associated with BE has increased almost 50% during the last 20 years. Meanwhile, the general population prevalence of BE is estimated to increase to 3-10% in Western countries. The systematic review and meta-analysis also reported an upward trend in prevalence of BE in Asian countries. BE is an important heathy issue to investigate in either Western or Asian countries.

The annual rate of developing esophageal adenocarcinoma is around 0.2% to 0.5% in patients with BE. However, the annual adenocarcinoma progression risk is different between the non-dysplastic Barrett's esophagus (NDBE), BE with low-grade dysplasia (LGD) and high-grade dysplasia (HGD). The annual incidence of esophageal adenocarcinoma is 0.33%, 0.54% and 6.58% in patients with NDBE, BE with LGD and HGD, respectively. Among patients with NDBE, patients with short segment BE (SSBE) have the lower rate of progression to EAC than those who with long segment BE (LSBE) (0.07% vs 0.25%). Therefore, endoscopic surveillance of patients with BE is recommended by clinical practice guideline.

Detections of goblet cells and dysplasia are crucial for diagnosis and determining the surveillance program of BE. According to the Seattle protocol which has been widely recommended by clinical practice guidelines, biopsy specimens should be obtained every one cm to two cm interval across the four quadrants of the columnar epithelium of esophagus. Fewer endoscopists adhered to this protocol in clinical practice because of its laboriousness and time consumption. Most of patients with BE were categorized as SSBE and SSBE seems to be more prevalent in Asian populations. As the report of previous study which reviewed the general prevalence of BE in Western and Asian general populations, the ratio of SSBE to LSBE was ranging from 1.8 to 17.4 in the Western countries and 1.7 to 103 in the Asian countries. It's more difficult to adhere to the protocol in patients with SSBE.

However, the optimal biopsy numbers and their yield rates of IM and dysplasia are still uncertain, especially in Asia. The investigators aimed to assess the biopsy numbers and yield rates of IM and dysplasia in patients with columnar-lined esophagus (CLE) to determine the optimal biopsy protocol.