Recommendations for Individuals with a Family History of Gastric Cancer
Individuals with a family history of gastric cancer should undergo endoscopic screening starting 10 years before the age of onset in the affected relative or by age 40 at the latest, with surveillance intervals determined by specific risk factors and endoscopic findings. 1
Risk Assessment and Screening Initiation
For First-Degree Relatives of Gastric Cancer Patients:
- Begin screening 10 years before the age of onset in the affected relative 2, 1
- If the relative had early-onset gastric cancer (before age 50), screening is particularly important as individuals with parents diagnosed before 50 develop gastric cancer approximately 10 years earlier than those without family history 3
- Minimum age to start screening: 40 years (if relative's diagnosis was after age 50) 1
- Optimal screening interval: Every 2 years (rather than the standard 3-year interval) if precancerous lesions are present 1, 4
For Hereditary Diffuse Gastric Cancer (HDGC):
- Genetic testing for CDH1 mutations is recommended for families meeting any of these criteria 2:
- Two or more documented cases of gastric cancer in first/second-degree relatives, with at least one confirmed diffuse gastric cancer
- Personal history of diffuse gastric cancer before age 40
- Personal or family history of diffuse gastric cancer and lobular breast cancer, with one diagnosed before age 50
Screening and Surveillance Protocols
For CDH1 Mutation Carriers:
- Annual endoscopic surveillance for individuals under age 20 2
- Prophylactic total gastrectomy recommended between ages 20-30 2
- For those declining gastrectomy: annual endoscopic surveillance with minimum of 30 random biopsies 2, 1
- For female carriers: annual breast MRI starting at age 30 2
For First-Degree Relatives Without Known Genetic Syndrome:
- High-definition white-light endoscopy with image enhancement 1
- Systematic biopsy protocol: minimum 5 total biopsies following the updated Sydney System, with separate labeling of samples from antrum/incisura and corpus 1
- If precancerous lesions found (atrophy, intestinal metaplasia), follow surveillance intervals based on histologic staging 1
- If no precancerous lesions found, continue screening every 2-3 years 1
H. pylori Management
- Test all individuals with family history of gastric cancer for H. pylori 1
- Eradication therapy should be initiated when H. pylori is detected, ideally by age 20, before precancerous lesions develop 1, 4
- H. pylori eradication is particularly important due to the synergistic effect of H. pylori infection and family history on gastric cancer risk 4
Additional Considerations
- Screening has shown high yield: A pilot study found 44% of asymptomatic first-degree relatives had gastric intestinal metaplasia and 7% had low-grade dysplasia 5
- Early detection is critical as endoscopic submucosal dissection can effectively treat early gastric cancer 6
- Consider additional risk factors that may compound family history risk:
Pitfalls to Avoid
- Delaying screening beyond recommended age, especially for those with relatives diagnosed with early-onset gastric cancer
- Inadequate biopsy sampling during endoscopy (minimum 30 random biopsies for CDH1 mutation carriers, minimum 5 biopsies for others)
- Neglecting H. pylori testing and eradication, which is crucial for prevention
- Using standard 3-year surveillance intervals when a 2-year interval is more appropriate for those with family history and precancerous lesions
- Failing to consider genetic testing for hereditary syndromes when multiple family members are affected
The evidence strongly supports that early and regular endoscopic screening can detect precancerous lesions and early gastric cancer in individuals with family history, potentially improving mortality outcomes through early intervention.