Is the Neosquamous Epithelium "Normal" Following Endoscopic Ablation of Dysplastic Barrett's Esophagus?

• To characterize the physiological and morphological properties of the neosquamous epithelium (NSE) [ Time Frame: Enrollment ] [ Designated as safety issue: No ]
  To characterize the physiological and morphological properties of the NSE, compared to native esophageal squamous epithelium in healthy controls and subjects with non-Barrett's Esophagus (BE) gastroesophageal reflux disease (GERD). We will compare the physiologic measures of NSE (intercellular space, total electrical resistance (RT), and fluorescein flux) to positive and negative controls using χ2 and Student's t tests.
• Correlate the physiologic and morphologic changes in the neosquamous epithelium (NSE) after ablation with the frequency and type of refluxate seen on pH-Impedance. [ Time Frame: Enrollment ] [ Designated as safety issue: No ]
  We will initially plot esophageal acid exposure (total time with esophageal pH<4) against intercellular space, total electrical resistance (RT), fluorescein flux and gastroesophageal reflux disease (GERD) sysmptom assessment scale (GSAS) scores. R values will be generated. Regression models using each of the 3 physiologic measures (RT, fluorescein, and intercellular space) as the response variable, and acid exposure and number of non-acid reflux events as predictor variables will be generated to define the relationship between reflux type and findings.

The investigators propose a study comparing the morphological and functional aspects of the neosquamous epithelium (NSE) after ablative therapy for dysplastic Barrett's esophagus (BE) to that of native squamous epithelium in normal controls as well as gastroesophageal reflux disease (GERD), non-Barrett's Esophagus (BE) subjects.

Purpose: We propose a study comparing the morphological and functional aspects of the neosquamous epithelium (NSE) after ablative therapy for dysplastic Barrett's esophagus (BE) to that of native squamous epithelium in normal controls as well as gastroesophageal reflux disease (GERD), non-BE subjects.

Participants: Eligible subjects will be women and men between the ages of 18-80, with one of the following:

1. Two or greater cm of dysplastic BE, who will undergo or have undergone radiofrequency ablation for BE at UNC, or
2. Diagnosed with GERD per a gastrointestinal (GI) physician undergoing upper endoscopy for other indications at UNC, or
3. Non-GERD controls per a GI physician with normal esophageal mucosa undergoing upper endoscopy for other indications at UNC.

Procedures (methods): Esophageal biopsies will be obtained specifically for research purposes before ablation therapy or, in subjects not receiving ablative therapy, after completion of the clinically indicated procedure and before withdrawal of the endoscope. Information from the medical record or from patient interview will be obtained regarding diagnosis (Barrett's esophagus, GERD, etc), and a questionnaire administered regarding the duration and frequency of reflux symptoms and complications of reflux disease. Subjects who are enrolled in the pre-ablation group will have additional biopsies and questionnaires administered during scheduled follow-up visits. On the last follow-up visit, this group will also undergo impedance-pH testing using standard methods, to assess for degree of control of esophageal acid exposure, and for number, duration and symptom correlation of non-acid reflux events.

Potential subjects will be identified by their gastrointestinal (GI) physician and approached by a study coordinator, nurse, or their GI physician regarding this study on the day of their scheduled procedure at UNC hospitals/GI clinic.

• Barrett's Esophagus
• Intestinal Metaplasia
• Gastroesophageal Reflux Disease (GERD)

• Radiofrequency Ablation (RFA)
  Participants in this group are greater than or equal to 12 months status post radiofrequency ablation (RFA).
• Radiofrequency Ablation Longitudinal (RFAL)
  Participants in this group are part of a longitudinal portion of the study and are enrolled prior to their first radiofrequency ablation procedure and followed at 6 and 12 months after completion of RFA.
• Gastroesophageal Reflux Disease (GERD)
  Participants in this group have been diagnosed with gastroesophageal reflux disease.
• Asymptomatic Controls (AC)
  Participants in this group are asymptomatic controls and enrolled as part of the comparison group.

Inclusion:

Eligible subjects will be mentally competent women and men between the ages of 18-80, able to speak and read English and who meet one of the following criteria:

• Two or greater cm of dysplastic Barrett's Esophagus (BE), who will undergo or have undergone radiofrequency ablation (RFA) for BE at the University of North Carolina, Chapel Hill (UNC), or
• Diagnosed with gastroesophageal reflux disease (GERD) per a GI physician undergoing upper endoscopy (EGD) for other indications at UNC, or
• Non-GERD controls per a GI physician with normal esophageal mucosa undergoing upper endoscopy for other indications at UNC.

Exclusion:

• Subjects with a bleeding diathesis or other contraindication of endoscopic biopsy.
• Current use of warfarin, heparin, and/or low molecular weight heparin (requires discontinuation of medication 5 days prior to and 7 days after EGD).
• Pregnant women