Cytosponge for Gastric Intestinal Metaplasia

Overview

Gastric cancer has a very poor prognosis. The disease is often diagnosed at a late stage, when curative treatment options are limited or ineffective. There is a condition that predisposes to gastric cancer, known in medical terms as Gastric intestinal metaplasia (GIM). This pre-cancerous condition can be diagnosed with an endoscopic camera test, but it often very subtle and can be missed at routine endoscopy. There is evidence that about 7% of gastric cancers are missed at previous endoscopy. The Cytosponge-trefoil factor 3 (TFF-3) is a pill on a string combined to a molecular biomarker which could help early diagnosis of gastric cancer and GIM. Cytosponge-TFF3 has been showed in previous research to be useful to diagnose Barrett's oesophagus, a condition of the food pipe similar to GIM. The aim of this study is to investigate the utility of the Cytosponge in combination with molecular biomakers to diagnose GIM

This is a case-control study whose goal is to compare the non-endoscopic test (Cytosponge-TFF3) to standard endoscopy to diagnose gastric intestinal metaplasia (GIM), a precursor lesion for gastric cancer. The main objective of the study is to determine the sensitivity and specificity of the Cytosponge-TFF3 to detect gastric intestinal metaplasia (GIM) affecting the proximal stomach. In parallel to this clinical study, a experimental study will be carried out aimed at evaluating the utility of molecular biomarkers to refine/improve the diagnostic accuracy of the Cytosponge test. The hypothesis is that the non-invasive Cytosponge, in combination with molecular biomarkers, can accurately detect GIM to the same extent as conventional, but more invasive, endoscopic procedures. Patients will be invited to participate in the study if they are due their surveillance endoscopy, because they have the disease of interest (GIM or GC; cases) or have been referred for an upper endoscopy for abdominal complaint (controls). On the day of the endoscopy the patient will swallow the Cytosponge under supervision of a trained research nurse prior to the endoscopic procedure. The participant will also provide information on demographics, clinical exposures (alcohol, tobacco, drugs), have measurements of weight and height taken and they will also complete a validated gastrointestinal symptoms questionnaire. A blood sample will be taken from the cannula used for the sedatives or through venepuncture. The patients will then undergo their planned endoscopy with additional sampling of gastric juice (suctioned through the endoscope) and some additional research biopsies in addition to a standardized clinical protocol to diagnose GIM. The above research procedures will be performed prior and during the endoscopy. No further research procedures will follow afterwards beyond the day of the endoscopy. The aim is to develop a non-invasive test which can be used to screen patients at risk for GIM to allow early detection and treatment of pre-cancerous gastric lesions and ultimately reduce the number of patients dying of gastric cancer.