STOMACH CANCER SCREENING
Screening is looking for cancer before a person has any symptoms. This can help detect cancer at an early stage, making it easier to treat because, by the time symptoms appear, cancer may already have begun to spread.
Stomach cancer is one of the most common cancers in the world. However, there are marked differences in the incidence of stomach cancer between regions. The value of screening for stomach cancer in asymptomatic patients is controversial, even in areas with a high stomach cancer incidence. In Vietnam, stomach cancer has the 3rd highest incidence rate after liver, lung, and breast cancer, and the age is younger and younger. We have operated on patients in their 20s, in cases of advanced disease, so life's prognosis is not good.
Means of screening
The tests are used to screen for different types of cancer. There are currently no standard or routine screening tests for stomach cancer. There are two main screening methods for stomach cancer: upper gastrointestinal endoscopy and a contrast gastric X-ray.
Upper endoscopy: endoscopy allows a direct view of the gastric mucosa and biopsy for definitive diagnosis of cancer as well as precancerous lesions such as atrophic gastritis, intestinal metaplasia, or gastric dysplasia. Although this method is more invasive and more expensive, it provides a more accurate diagnosis of other stomach lesions. Today, using new generations of endoscopes that help detect cancer early and receive radical treatment by endoscopy, we have improved prognosis and quality of life.
Barium-meal gastric photofluorography: Double-contrast can identify malignant stomach ulcers, infiltrative lesions, and some early stomach cancers. However, the false-negative rate is up to 50%, and the sensitivity in detecting early stomach cancer is only 14%. The case where x-rays have a better diagnosis than gastroscopy is linitis plastica cancer.
Other tests:
Blood pepsinogen level. A test that measures the concentration of pepsinogen in the blood. Low levels of pepsinogen are a sign of chronic atrophic gastritis that can lead to stomach cancer.
Serum Trefoil factor 3. Serum trefoil factor 3 (TFF3) is a small stable protein expressed in the goblet cells of the small and large intestine and in gastric intestinal metaplasia. The combination of pepsinogen and TFF3 may result in a higher susceptibility to stomach cancer.
MicroRNS. At least 3 microRNAs, miRNA-421, miRNA 18a, and miR-106a, are highly present in stomach cancer and detected in peripheral blood and gastric aspirate.
Stomach cancer screening strategy
Stomach cancer screening is a controversial issue, and there are different screening recommendations based on the incidence of stomach cancer.
Studies show that screening many people for stomach cancer using these tests has not reduced the risk of dying from stomach cancer.
Population-based screening has been done in some countries with high stomach cancer rates, such as Japan, Korea, Venezuela, and Chile. However, the recommended screening methods and testing timing vary. Example:
In Japan, screening is recommended for ages 50 and older with a double contrast x-ray every year or a gastrointestinal endoscopy every 2-3 years.
In Korea, upper gastrointestinal endoscopy is recommended every two years for people aged 40-75.
In countries like Japan, where stomach cancer is very common, widespread screening has helped detect many early cancer cases that can be cured. This may reduce the number of people dying from the disease, but it has not been proven. Scientists believe that people with certain risk factors may benefit from screening for stomach cancer.
Screening selectively in high-risk groups
Patients at high risk should be screened with an upper GI endoscopy, including:
Gastric adenomas
Pernicious anemia
Gastric intestinal metaplasia
Family adenomatous polyposis (FAP)
Lynch Syndrome
Peutz-Jeghers syndrome
Juvenile polyp syndrome
The Risks of Stomach Cancer Screening
Stomach cancer screening may have the following risks:
Screening may not improve your health or help you live longer if stomach cancer has advanced.
Some cancers never cause symptoms or are life-threatening, but cancer can be treated if found by a screening test. It is not known whether treatment for cancer will help you live longer or if left untreated, and cancer treatments could have serious side effects.
False-negative test results can occur.
Test results may be normal even though stomach cancer is present. A person who receives a false negative can delay treatment even if symptoms appear.
False-positive test results can occur.
The test results may appear abnormal despite the fact that there is no cancer. A false-positive test result can cause anxiety and continues to be searched because many tests and procedures are also risky. The screening tests themselves can cause side effects.
Endoscopy can cause rare but serious complications
Perforation of the esophagus or stomach
Heart problems
Shortness of breath
Pneumonia is caused by inhaling food, fluid, or stomach acid into the lungs
Severe bleeding requires treatment in a hospital
Reactions to drugs used during endoscopy
March 4, 2021
HUNG M. DO, MD, Ph.D