Gastric cancer (GC) is the fourth cause of cancer-related death and the fifth most common diagnosed cancer worldwide with 1 million new cases per year. GC is mainly associated with a poor prognosis, highlighting the importance of its early detection. GC results from a multistep process starting from a gastric chronic inflammation preceding atrophic gastritis (AG), the development of preneoplasia (intestinal metaplasia (IM), dysplasia (Dys) and then cancer lesions. Presently, GC can only be diagnosed by endoscopy, which is an invasive, and costly method with its limits. Indeed, preneoplasia as Dys can escape endoscopic detection. Therefore, the discovery of blood-based biomarkers to identify the presence of gastric preneoplasia and/or cancer lesions at the earliest, at an asymptomatic stage, is of paramount interest. It is crucial not only for the early detection/prevention of individuals at risk of GC but also useful for patient follow-up to predict disease recurrence/outcome and to monitor treatment. Using plasma samples from patients at various stages of the GC cascade, we previously identified two signatures of 6 protein candidates to predict the presence of preneoplasia and GC lesions. Based on these data, the goal of this study is to further test and validate these different signatures, and to improve their predictive ability at the earliest stages of the GC cascade, taking into account the different types of gastric preneoplasia, IM and Dys, and their grade of severity. To achieve this goal, a large multicentric cohort of patients will be established including different groups of plasma samples covering the most complete panel of the type/grades of gastric preneoplasia as well as at early stages of GC. These plasma samples will be then used to measure the level of the different signature components using various method of analysis as immuno-based assays.
The goal of this study is to characterize and validate a signature of circulating biomarkers in plasma, associated with the presence of gastric preneoplasia in patients with preexisting gastric lesion compared with a control group.~For this purpose:~Patients with pre-existing gastric lesions will be invited to participate to this study. If they are willing to participate an additional blood sample (10mL) will be collected at the time of the blood collection performed during their routine care~Healthy subjects will be invited to participate to constitute the control group. If they are willing to participate a blood sample (10 ml) will be drawn specifically for this study