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

• To characterize reflux symptomatology before and after radiofrequency ablation in subjects with dysplastic Barrett's Esophagus (BE). [ Time Frame: Enrollment ] [ Designated as safety issue: No ]
  To characterize reflux symptomatology before and after radiofrequency ablation in subjects with dysplastic BE. We will compare before and after gastroesophageal reflux disease (GERD) symptom assessment scale (GSAS) symptom scores using paired Student's t tests. As an exploratory analysis, we will further stratify the data by PPI use (once- vs. twice-daily.
  
  

• 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.
  
  

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.