This research will eventually lead to the identification of inherited genetic changes that cause Barrett's esophagus and esophageal cancer. It will help the investigators develop better methods for preventing or identifying esophageal cancer at an early curable stage.
The capsule can be swallowed with a few sips water. Once the capsule is advanced to 45-50 cm from the incisors and reaches the stomach the balloon is inflated to a size of 16 mm with 5.5 cc air. It is withdrawn until a tug is felt to locate the gastroesophageal junction (GEJ). The inflated balloon is then pulled back 3 to 5 cm to sample the distal esophagus, then completely deflated to cause inversion of the biospecimen into its protective capsule, and then withdrawn. The balloon is re-inflated outside the patient and the obtained sample is clipped with scissors into a vial and frozen. The collected biospecimen will be stored frozen for later DNA extraction and assay. The vials will be labeled with a coded sample number. In a pilot study of 120 subjects this capsule esophageal sampling was performed with no adverse events reported. Similar esophageal sampling devices have been reported on over 1600 patients with no adverse events.
All patients will also undergo standard EGD. Patients with BE or EAC will have standard of care surveillance and diagnostic biopsies. All cases and controls will have research esophageal brushings from the BE/EAC and distal esophagus/gastric cardia, respectively. Cases and controls will also obtain research brushings from the proximal normal squamous esophagus. Research mucosal biopsies will also be obtained from the BE and EAC epithelium as well as normal stomach and duodenum in cases and from the gastric cardia and the distal squamous esophagus as well as normal stomach and duodenum in controls. Biopsies from BE and EAC will be directed by using high definition narrow band imaging. Biospecimens, brushings and biopsies, will be snap frozen at bedside and stored for future research assays. Although we do not anticipate any problems with our non-endoscopic balloon screening, these archived pathology samples and snap frozen samples will be available for assay in case we fail to detect our markers in patients with BE diagnosed at EGD or experience a high false positive rate. Subjects who undergo non-endoscopic sampling of the distal esophagus will be asked questions that rate their discomfort on a Likert scale and also asked questions comparing the non-endoscopic sampling study with an EGD.
