In HDGC with exclusive DGC manifestation, endoscopic surveillance seems insufficient to detect early gastric lesions associated with CDH1 mutations, because the tumor is often multifocal, tumor cells infiltrate the mucosa, the epithelium presents a normal surface, and each focus is usually less than 1 mm in diameter at most.28 The gene discussed is CDH1; the disease is CDH1-related diffuse gastric and lobular breast cancer syndrome.