Screening for Familial Gastric Cancer in First Degree Relatives

Inclusion Criteria: * adult (≥ 18 yrs), female and male relatives * fully legal competent (to simplify the common consent agreement for blood withdrawal, DNA analysis and serial endoscopies.) * individuals that signed the common consent agreement * first degree relative of an individual with diffuse gastric cancer from a FDGC-family, without proven mutation, * OR: 2 or more individuals with gastric carcinoma, at least one \< 50 yrs * OR: 3 or more individuals with (diffuse/intestinal/other type) gastric carcinoma, any age * OR 1 individual with any type gastric carcinoma \< 40 yrs Exclusion Criteria: * immature individuals * actual gastric ulcer or gastric bleeding * previous diagnosis of gastric cancer * hypersensitivity to Indigocarmine * individuals with co-morbidity which might increase the sedation and/or endoscopy risk: COPD Gold III/IV Cardiac failure Increased bleeding tendency or use of medication which increases bleeding tendency