Hereditary Diffuse Gastric Cancer testing criteria has been established and is considered in families who meet any of the following criteria.
In addition, families in whom testing could be considered are those who meet any of the following criteria.
Affected patients from families meeting the criteria are referred for genetic counseling and testing for a CDH1 gene mutation. The genetic testing is performed in two stages, diagnostic testing and predictive testing. Diagnostic testing is done using a blood sample from a patient affected with gastric cancer, to identify if a mutation in the CDH1 gene exists to cause the cancer. If a mutation is identified, healthy family members who are at risk for inheriting the same mutation may choose to undergo predictive testing for the same mutation.
People from HDGC families are at an increased risk of developing diffuse-type gastric cancer and lobular breast cancer. It is estimated that the risk of developing gastric cancer by age 80 is 70% in men and 56% in women. Additionally, female carriers are at an increased risk (42% by age 80) for lobular breast cancer.
Caldas C, Carneiro F, Lynch HT, Yokota J, Wiesner GL, et al. Familial gastric cancer: overview and guidelines for management. Journal of Medical Genetics. 1999;36:873-880.
Vogelaar IP, van der Post RS, Carneiro F, Guilford P, Huntsman D, et al. Hereditary diffuse gastric cancer: updated clinical guidelines with an emphasis on germline CDH1 mutation carriers. J Med Genet. 2015;00:1-14.