Subtle endoscopic manifestations of diffuse signet cell gastric adenocarcinoma in patients with CDH1 mutations

Two patients with CDH1 mutations underwent hereditary diffuse gastric cancer (HDGC) protocol baseline endoscopies. A 52-year-old woman, whose sister had died of lobular breast cancer and whose 29-year-old niece had a diffuse gastric cancer, had a patch of pale mucosa (A, B), with targeted biopsies showing intramucosal signet cell adenocarcinoma. The total gastrectomy specimen had multifocal intramucosal poorly differentiated signet cell...