The ultimate goal of the Barrett's Esophagus Patient Registry is to help develop more effective targeted screening strategies and treatment options for Barrett's esophagus and esophageal adenocarcinoma (EAC). We plan to do by developing a registry that will serve as a platform. Examples of analyses could include identifying genetic determinants and biomarkers that predict BE, progression of BE to EAC, as well as the response to therapies.

Inclusion Criteria:

• Barrett's (BE): Patients who have Barrett's esophagus (all stages: Barrett's metaplasia, low-grade dysplasia, high-grade dysplasia) based upon standard endoscopic and histologic criteria.
• Adenocarcinoma (EAC): Patients who have esophageal adenocarcinoma.
• The control cohort will include patients ages 18 and older with no prior history of BE and EAC. These may include patients who are being seen or have been previously seen at MGH GI Associates for conditions including gastroesophageal reflux disease, peptic esophagitis, eosinophilic esophagitis, esophageal motility disorders such as achalasia and nutcracker esophagus.

Exclusion Criteria:

• Inability or unwillingness to provide blood samples.
• History of known bleeding disorders.
• Currently awaiting organ transplantation.
• Having an acute or severe chronic illness such as congestive heart failure or any other condition that would prohibit performing the endoscopy.

Patients who have been seen at Massachusetts General Hospital.