Esophageal adenocarcinoma (EAC) is a deadly cancer that is preceded by a metaplastic change called Barrett's esophagus (BE). It has long been thought that endoscopic screening for BE followed by endoscopic surveillance can significantly decrease the mortality of EAC. This unfortunately has not borne out as the cost and inconvenience of conscious sedation prohibits endoscopy from being used as a population-based screening tool. BE screening may become possible in the future, owing to innovative swallowable tethered capsule endomicroscopes or cell sampling devices that can detect BE without requiring sedation. Yet, even if these capsules were to identify the large number of people in the US who have BE (~15M), endoscopic surveillance of this group would be prohibitively expensive. If we could use tissue biomarkers to identify the 5% of those with BE who will develop EAC in their lifetimes, then endoscopic intervention could be given to those who really need it, and those with low-risk BE would not require further follow up. Recognition of this need has motivated the field to identify BE progression biomarkers derived from esophageal tissue samples obtained by autofluorescence/reflectance-targeted endoscopy. This research has identified biomarkers such as aneuploidy and aberrant p53/cyclin A expression as strong predictors of BE progression. Unfortunately, the only way to target and obtain these tissues today is through sedated endoscopy. With the modifications proposed here, a new BE screening technology that we have developed called optical coherence tomography (OCT) tethered capsule endomicroscopy (TCE), could enable targeted biopsy without sedation. OCT-TCE obtains 3D microscopic images of the entire esophagus in unsedated subjects, accurately identifies BE, and has been successfully used by nurses and technicians in primary care settings. Here, we propose to advance OCT-TCE for targeted biopsy by adding autofluorescence and reflectance spectral imaging technology that can help identify tissue enriched in molecular alterations associated with BE progression risk. The new capsule will also have a cryobiopsy mechanism for acquiring targeted tissue samples under real time image guidance. In Aim 1 of this proposal, we will develop this multimodality TCE with biopsy (MM-TCEB) device and show that it works as intended in a study of 20 BE patients. Then, we will conduct a clinical study in 100 unsedated BE patients to demonstrate that MM-TCEB collects tissue and identifies BE progression biomarkers as well as sedated endoscopy. In Aim 3, we will develop image analysis and deep learning algorithms to mine the Aim 2 data, uncovering new relationships between OCT, autofluorescence, and reflectance spectroscopy and tissue-derived BE progression biomarkers. By acquiring targeted biopsies using a swallowable tethered capsule in unsedated subjects, MM-TCEB can become a powerful technique for obtaining esophageal tissue samples for BE progression biomarker dis...