Gastric Cancer: Causes, Symptoms, Diagnosis, Treatment, and Prevention
Known also as stomach cancer, gastric cancer develops in the stomach lining. Among the most common cancers in the world, it is the third leading cause of death from cancer. Although stomach cancer can affect any part of the stomach, it usually occurs near the small intestine opening.
Causes of Gastric Cancer
The exact cause of gastric cancer is not known, but some factors may increase the risk of developing it. These include:
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Helicobacter pylori (H. pylori) infection: This is a common bacterial infection that can cause inflammation and ulcers in the stomach. H. pylori infection is associated with about 60% of gastric cancer cases.
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A diet high in smoked, salted, or pickled foods, or foods containing nitrites or nitrates (such as cured meats) may increase the risk of gastric cancer.
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Smoking: Smoking tobacco can damage the cells that line the stomach and increase the risk of gastric cancer. The risk is higher for heavy smokers and those who started smoking at a young age.
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Heavy smokers and those who started smoking at a young age are more likely to develop gastric cancer if they smoke tobacco shared environmental factors.
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A close relative with gastric cancer (such as a parent, sibling, or child) may increase your risk. It may be caused byk of gastric cancer. Also, having a history of stomach surgery or radiation therapy to the abdomen may increase the risk.
Symptoms of Gastric Cancer
Gastric cancer may not cause any symptoms in the early stages, or the symptoms may be vague and easily mistaken for other conditions. Some of the possible symptoms of gastric cancer are:
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Indigestion, heartburn, or stomach pain
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Nausea, vomiting, or loss of appetite
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Bloating, fullness, or discomfort after eating
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Weight loss or weakness
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Difficulty swallowing or feeling of food stuck in the throat
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Blood in the stool or vomit
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Anemia or low red blood cell count
Diagnosis of Gastric Cancer
If gastric cancer is suspected, the doctor may perform several tests to confirm the diagnosis and determine the stage of the cancer. These tests may include:
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Physical exam and medical history: The doctor will ask about the symptoms, risk factors, and family history of the patient, and examine the abdomen for any signs of swelling, tenderness, or fluid buildup.
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Blood tests: The doctor may order blood tests to check for anemia, infection, or other abnormalities that may indicate gastric cancer.
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A doctor may order blood tests to check for anemia, infection, or other abnormalities that couldoscope) to examine the inside of the esophagus, stomach, and duodenum (the first part of the small intestine). The doctor may also take a biopsy (a small sample of tissue) from the stomach for further analysis.
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Imaging tests: The docprocedure involves using an endoscope (a thin, flexible tube with a light and camera) to examine the inside of the esophagus, stomach, and duodenum (the first part of the small intestine). As part of the analysis, the doctor may also take a small sample of stomach tissue (a biopsy).pread of the cancer.
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Depending on the results of the tests, the doctor will assign a stage to the cancer, ranging from stage 0 (the earliest stage) to stage IV (the most advanced stage).
Treatment of Gastric Cancer
The treatment of gastric cancer depends on several factors, such as the stage of the cancer, the location and size of the tumor, the patient’s age, health, and preferences, and the availability of resources. The main types of treatment for gastric cancer are:
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An early-stage gastric cancer is treated most commonly with surgery. The goal of surgery is to remove the tumor, some healthy tissue, and lymph nodes near the tumor. Depending on the extent of the cancer, the surgeon may perform a partial gastrectomy (removal of part of the stomach), a total gastrectomy (removal of the entire stomach), or a subtotal gastrectomy (removal of the lower part of the stomach). It is also possible for the surgeon to reconnect the remaining stomach or esophagus to the small intestine, or to create a new stomach pouch from the small intestine.
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As the name suggests, chemotherapy involves using drugs to kill or stop cancer cells from growing. The goal of chemotherapy is to shrink the tumor before surgery (called neoadjuvant chemotherapy) or to destroy any remaining cancer cells after surgery (called adjuvant chemotherapy) to prevent recurrence. Advanced or metastatic gastric cancer that cannot be removed by surgery can also be treated by chemotherapy alone or in combination with other treatments.
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In radiation therapy, high-energy rays or particles are used to destroy or damage cancer cells. For advanced or metastatic gastric cancer, radiation therapy can be given before or after surgery, or in combination with chemotherapy, to reduce the risk of recurrence. A radioactive source placed inside the body near the tumor can provide radiation therapy externally (from a machine outside of the body).
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It involves the use of drugs that target specific molecules or pathways involved in the growth and survival of cancer cells. Advanced or metastatic gastric cancer with certain genetic or molecular characteristics, such as overexpression of human epidermal growth factor receptor 2 (HER2) or mutations of epidermal growth factor receptors (EGFR) or vascular endothelial growth factors (VEGF), can be treated with targeted therapy alone or in combination with chemotherapy or radiation therapy.
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As part of immunotherapy, drugs are used to stimulate or enhance the body's immune system to fight cancer cells. When advanced or metastatic gastric cancer has certain characteristics, such as high levels of programmed death-ligand 1 (PD-L1) or microsatellite instability (MSI), immunotherapy can be used alone or in combination with chemotherapy or targeted therapy.
Prevention of Gastric Cancer
There is no sure way to prevent gastric cancer, but some lifestyle changes may help reduce the risk. These include:
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It is possible to detect H. pylori infection by blood tests, breath tests, stool tests, or biopsy. In order to eradicate the bacteria and heal the stomach lining, a combination of antibiotics and acid-suppressing drugs may be prescribed if the infection is confirmed.
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You may help reduce your risk of gastric cancer by eating more fruits and vegetables, especially those rich in vitamin C, and less smoked, salted, pickled, or nitrite- or nitrate-containing foods. The stomach can also be protected if you drink enough water and limit alcohol consumption.
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Tobacco smoke damages the cells lining the stomach and increases the risk of gastric cancer. Quitting tobacco can reduce the risk and improve overall health.
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The doctor may recommend regular screening tests, such as upper endoscopy, to detect any precancerous or cancerous changes in the stomach for people who have a high risk of gastric cancer, such as those who have a family history of the disease. It is possible to improve survival and recovery chances when gastric cancer is detected and treated early.
