Inclusion Criteria:  All adults 18 years of age of older undergoing upper or lower endoscopy for routine medical care.  Exclusion Criteria:  Persons with current malignancy Persons with history of malignancy and treatment within last 5 years of enrollment, excluding non-melanoma skin cancer or cervical in-situ. Persons who are unable or unwilling to provide repeat blood samples and complete follow-up questionnaires Persons who lack the capacity to provide consent Persons who do not speak English Persons who are visually or hearing impaired.