DOI: 10.1158/1940-6207.capr-26-0102 ISSN: 1940-6207

Long-term Endoscopic Surveillance in Hereditary Diffuse Gastric Cancer Syndrome

Muhan Li, Danielle Lynch, Tanushka Dewan, Kajal Patel, Devanshi Patel, Daniel C. Chung

Abstract

Hereditary Diffuse Gastric Cancer (HDGC) syndrome arises from a germline variant in CDH1 and is characterized by a high risk of gastric signet-ring cell carcinoma. Total gastrectomy is the most definitive strategy for cancer risk reduction but carries high morbidity. Endoscopic surveillance is an alternative, but there are limited data on long-term outcomes with this approach. We sought to define the outcomes of long-term endoscopic surveillance in a HDGC cohort. We retrospectively analyzed the demographic, clinical, endoscopic, and histopathological records of 102 patients with pathogenic or likely pathogenic (P/LP) CDH1 variants at Massachusetts General Hospital. We defined short-term endoscopic surveillance as less than 3 years and long-term surveillance as 3 years or longer. The HDGC cohort included 68 female and 34 male patients, with a mean age at diagnosis of 42.1 years. Thirty-four patients opted for immediate risk-reducing gastrectomy and 40 pursued endoscopic surveillance. 20 individuals comprised the short-term surveillance group (median follow-up 1.4 years) and there were 20 individuals in the long-term surveillance group (median follow-up 5.1 years). There were two cases of advanced gastric cancer (>T1a) identified, and both occurred in the long-term surveillance group. Both were managed with gastrectomy and remain cancer-free. There were no gastric cancer-related deaths. In this series, long-term endoscopic surveillance identified advanced gastric cancers in HDGC at treatable stages without any gastric cancer-related mortality. These findings suggest endoscopic surveillance may be a reasonable long-term strategy in HDGC for select individuals.