Oncologists remind clinicians that for patients with upper abdominal pain, acid regurgitation, belching, nausea, vomiting, upper abdominal fullness, anorexia, weight loss, especially those over 40 years old, there should be a high alert for the possibility of gastric cancer. In gastric cancer screening, people under 40 years old should also be listed as screening candidates, especially those with a family history of gastric cancer, who should be regarded as key targets.