Pilot Study for OCT Guided In Vivo Laser Capture Microdissection for Assessing the Prognosis of Barrett's Esophagus

Overview

The investigators have developed a new technology, termed in-vivo laser capture microdissection (IVLCM), that addresses the limitations of endoscopic biopsy for screening for BE and provides targeted genomic profiling of aberrant tissue for more precise prediction of EAC risk. The device is a tethered capsule endomicroscope (TCE) that implements optical coherence tomography (OCT) to grab 10-mm-resolution, cross-sectional microscopic images of the entire esophagus after the capsule is swallowed. This OCT-based TCE technology is used in unsedated patients to visualize images of BE and dysplastic BE. During the IVLCM procedure, TCE images of abnormal BE tissue are identified in real time and selectively adhered onto the device. When the capsule is removed from the patient, these tissues, targeted based on their abnormal OCT morphology, are sent for genomic analysis. By enabling the precise isolation of aberrant esophageal tissues using a swallowable capsule, this technology has the potential to solve the major problems that currently prohibit adequate BE screening and prevention of Esophageal Adenocarcinoma EAC.

In Vivo Laser Capture Microdissection (IVLCM). The IVLCM tethered capsule is identical to those used in current approved OCT TCE studies.The capsule is swallowed by the patient and then, in real time, a region for tissue capture, is identified on the images. When a targeted site is identified, a capture laser (1450 nm, 0.8 W, 1 second exposure; within the range of the previously approved OCT-TCE tissue marking study) irradiates this area in the patient, heating the water in the tissue and transforming it to steam. The accumulated water steam overcomes the tissue matrix's adhesion force, ejecting a small amount of tissue and integrating it with the capsule's external shell. This process may then be repeated to collect multiple samples. After the device is pulled out from the patient, the captured tissues can be extracted for genomic analysis. Ex vivo animal tissue studies have shown that capture laser does not damage DNA/RNA; high quality whole genome information can be obtained. In this IVLCM study, the investigators are using a 1450 nm laser to capture tissue that was previously approved to make cautery "marks" in the esophagus. The IVLCM capture laser's specifications are the same as those of the marking laser and the power will be within the IRB approved power range (0.82 W 1s). Prior to testing laser marking in humans, the investigators first demonstrated the safety of laser marking in animals in vivo. Histological assessment showed that the cautery marks did not penetrate through the submucosa and the vast majority of the effects were limited to the epithelium, lamina propria, and muscularis mucosa layers. The extent of thermal damage was comparable to conventional biopsies in standard of care endoscopic biopsy procedures. After this animal study, the investigators conducted a pilot study in humans in which over 30 marks were made in 22 enrolled subjects without any adverse events or safety concerns. In addition to these balloon studies, the investigators are currently conducting a TCE marking study. So far, the investigators have imaged and marked 13 subjects through a capsule without any adverse effects or safety concerns. Thirty (N=30) subjects will be enrolled in this study.