Gastric In Vivo Study

Overview

The overall objective of this pilot study is to determine whether multispectral imaging increases the diagnostic accuracy of the current standard of high-definition white-light endoscopy for the detection of gastric neoplasia (high grade dysplasia or cancer). As part of an NCI-funded RO1, the investigators goal is to develop a multispectral endoscopic platform that can be used to survey a large surface area and, potentially, serve as a "red flag" for microendoscopic imaging of small areas. In prior ex vivo evaluations of surgical and endoscopic specimens, the investigators have identified the optical settings and illumination wavelengths that are complementary to white-light imaging and enhance superficial mucosal and vascular changes associated with neoplasia. Based on this initial testing, vital-dye enhanced fluorescence imaging (VFI) and imaging with High Resolution Microendoscope (HRME) have been identified as modalities that may be complementary to white-light imaging. The goal of this pilot study is to preliminarily determine the accuracy of these modalities during the endoscopic surveillance and detection of gastric neoplasia.

Consent will be obtained the day of the subject's scheduled endoscopy in a clinical room or at a routine office visit prior to the endoscopy. The study investigator will explain the study including the reasons why subject may be eligible, risks, and benefits. The subject will be given a chance to address any questions or concerns they may have. If the patient agrees to participate in this study all of the procedures listed below will be performed the day of the scheduled endoscopy exam. The procedures listed are part of the routine standard of care for an endoscopy exam, except for the images that are being taken and the additional 2-6 biopsies taken from any abnormal areas that are seen with the new imaging technique. The use of the imaging technique described in this research study will not change the standard of care procedures. The endoscopic procedure is outlined below: 1. White Light Examination: Examination will initially be performed in the standard white-light endoscopic mode as is routinely done. Abnormal gastric mucosa areas and nodularities will be recorded. Any "Suspicious" areas (visible abnormalities, etc.) will be photographed and the location recorded (distance from incisors and endoscopic quadrant, eq. 34 cm; greater curvature, lesser curvature, etc). 2. Vital-Dye Enhanced Fluorescence Examination: Following this, the stomach will be sprayed with 1-10 ml of 0.01% proflavine using a standard endoscopic spray-catheter. Using the fluorescent imaging, the location of any VFI-"Suspicious' areas will be recorded. Additionally, VFI examination of any suspicious areas seen on WLE will be performed. The endoscopist will label the surface-appearance of each WLE abnormal area based on its VFI appearance. Thus, each area will be labeled as: "Not Suspicious," or "Suspicious for Neoplasia." 3. HRME examination: WLE and VFI suspicious appearing areas will be further imaged with HRME. HRME will be inserted through the biopsy channel of the endoscope, gently placed against the mucosa, and images of suspicious areas will be obtained. The endoscopist will label the surface-appearance of each WLE abnormal area and VFI abnormal area, based on the HRME appearance. Thus, each area will be labeled as: "Not Suspicious," or "Suspicious for Neoplasia." 4. Biopsy Protocol: Biopsies will be obtained of any area suspicious on any of the imaging modalities (WLE, VFI or HRME). Additionally, two 'control' areas (normal on imaging) will also be biopsied. Lastly, routine, biopsies will be performed per clinical care to determine areas of intestinal metaplasia and H pylori infection as per routine standard of care. 5. Pathologic Interpretation: All samples will be evaluated by a single expert gastrointestinal pathologist who will be blinded to the endoscopic findings