Recent guidelines from the international gastric cancer linkage consortium (IGCLC) have revised the definition of HDGC to the presence of a CDH1 or CTNNA1 GPV in either an individual with DGC, or unaffected individual with a family pedigree featuring one or more DGC cases in first-degree or second-degree relatives, with or without a personal or family history of lobular breast cancer [27]. This evidence concerns the gene CDH1 and gastric cancer.