The development of gastric cancer is the result of a combination of factors, and genetic factors are also very likely to be one of the factors that influence the development of gastric cancer. For those who are at risk, a genetic risk assessment for gastric cancer, to know whether they and their relatives carry mutations related to gastric cancer, can help to make targeted lifestyle adjustments to prevent or delay the onset of gastric cancer, or even to take appropriate medical countermeasures under the guidance of a doctor. This article takes a look at the genetic risk assessment for gastric cancer.
Who needs to be evaluated?
According to the National Comprehensive Cancer Network (NCCN) guidelines for gastric cancer, the following people are appropriate to be evaluated for genetic risk of gastric cancer (one or more of the following):
- Gastric cancer before age 40;
- Gastric cancer before age 50 with 1 first- or second-degree relative with gastric cancer;
- Gastric cancer at any age with at least 2 first- or second-degree relatives with gastric cancer;
- Gastric cancer at any age with at least 2 first- or second-degree relatives with gastric cancer;
- Gastric cancer and breast cancer, one of which was diagnosed before age 50;
- Gastric cancer at any age with a family history of breast cancer and a first- or second-degree relative diagnosed with breast cancer before age 50;
- Gastric cancer at any age with a family history of juvenile polyps or gastrointestinal polyps;
- Gastric cancer at any age and a family member with an inherited non-polyposis colorectal cancer (Lynch syndrome)-associated tumor (colorectal, endometrial, small bowel, or urinary tract tumor).
In addition to the above, genetic risk assessment for gastric cancer (meeting one or more of the following) is also generally recommended for those with a family history of:
- The presence of a known gastric cancer susceptibility gene mutation in a close relative;
- 1 first- or second-degree relative with gastric cancer diagnosed before age 40 years;
- 2 first- or second-degree relatives with gastric cancer diagnosed before age 40 years;
- 2 first- or second-degree relatives with gastric cancer, one of whom was diagnosed before age 50 years;
- 3 first- or second-degree relatives with gastric cancer (regardless of age);
- 3 first- or second-degree relatives with gastric cancer (regardless of age);
- 1 first- or second-degree relative with gastric cancer and breast cancer, one of whom was diagnosed before age 50, or 1 next of kin with juvenile polyposis, or 1 next of kin with gastrointestinal polyposis.
To add to this, there are first-, second-, and third-degree relatives, where first-degree relatives are parents, siblings, and children, second-degree relatives are grandparents, maternal grandparents, and siblings of parents, and third-degree relatives are great-grandparents and cousins and siblings.
What does the assessment include?
Because the process of genetic counseling and risk assessment involves genetic testing, psychological status, social status, and other issues that involve the privacy of the person being evaluated, the person being evaluated has the right to know about the entire process and informed consent is required before the assessment can begin. The specific assessment includes the following.
- Get a detailed family history;
- Knowing a detailed history of previous medical disease and surgical treatment;
- Examination for manifestations related to gastric cancer;
- Assessment of psychological situation, social condition;
- Assessment of the assessed person’s risk of developing gastric cancer;
- Education on gastric cancer prevention and treatment;
- Analysis and interpretation of genetic test results.
To be clear, the most effective strategy for identifying oncogenic mutations in families is genetic testing of close relatives who have cancer, but if the relative is unwilling or unable to undergo genetic testing, genetic testing of relatives who do not have cancer is also available.
Those undergoing a genetic risk assessment for gastric cancer should not only clearly understand what the assessment entails and cooperate with the specialist, but also understand that the entire assessment process requires the early involvement of a health professional with experience and expertise in oncogenetics. Since the assessment process involves a lot of education and communication discussions, mutual trust and good communication between the specialist and the person being assessed is especially important.