Definition: Stomach cancer is cancer that starts in the stomach.
Several types of cancer can occur in the stomach. The most common type is called adenocarcinoma. It starts from one of the cell types found in the lining of the stomach.
Adenocarcinoma is a common cancer of the digestive tract. It is not very common. It is diagnosed much more often in people in eastern Asia, parts of South America, and eastern and central Europe. It occurs most often in men over age 40.
The number of people who develop this cancer has decreased over the years. Experts think this decrease may be in part because people are eating less salted, cured, and smoked foods.
You are more likely to be diagnosed with gastric cancer if you:
- Have a diet low in fruits and vegetables
- Have a family history of gastric cancer
- Have an infection of the stomach by a bacteria called Helicobacter pylori (H pylori)
- Had a polyp (abnormal growth) larger than 2 centimeters in your stomach
- Have inflammation and swelling of the stomach for a long time (chronic atrophic gastritis)
- Have pernicious anemia (low number of red blood cells from intestines not properly absorbing vitamin B12)
Symptoms of stomach cancer may include any of the following:
- Abdominal fullness or pain, which may occur after a small meal
- Dark stools
- Difficulty swallowing, which becomes worse over time
- Excessive belching
- General decline in health
- Loss of appetite
- Vomiting blood
- Weakness or fatigue
- Weight loss
Diagnosis is often delayed because symptoms may not occur in the early stages of the disease. And many of the symptoms do not specifically point to stomach cancer. So, people often self-treat symptoms that gastric cancer has in common with other, less serious, disorders (bloating, gas, heartburn, and fullness).
Tests that can help diagnose gastric cancer include:
- Complete blood count (CBC) to check for anemia.
- Esophagogastroduodenoscopy (EGD) with biopsy to examine the stomach tissue. EGD involves putting a tiny camera down the esophagus (food tube) to look at the inside of the stomach.
- Stool test to check for blood in the stools.
Surgery to remove the stomach (gastrectomy) is the standard treatment that can cure adenocarcinoma of the stomach. Radiation therapy and chemotherapy may help. Chemotherapy and radiation therapy after surgery may improve the chance of a cure.
For people who cannot have surgery, chemotherapy or radiation may improve symptoms and may prolong survival, but may not cure the cancer. For some people, a surgical bypass procedure may relieve symptoms.
You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.
Outlook varies based on how much the cancer has spread by the time of diagnosis. Tumours in the lower stomach are cured more often than those in the higher stomach. Chance of a cure also depends on how far the tumour has invaded the stomach wall and whether lymph nodes are involved.
When the tumour has spread outside the stomach, a cure is less likely. When a cure is not possible, the goal of treatment is to improve symptoms and prolong life.
Call your health care provider if symptoms of gastric cancer develop.
Screening programs are successful in detecting disease in the early stages in parts of the world where the risk of stomach cancer is much higher than in Canada or the United States. The value of screening in Canada, the United States and other countries with much lower rates of stomach cancer is not clear.
The following may help reduce your risk of stomach cancer:
- DO NOT smoke.
- Keep a healthy diet rich in fruits and vegetables.
- Take medicines to treat reflux disease (heartburn), if you have it.
- Take antibiotics if you are diagnosed with H pylori infection.
Gunderson LL, Donohue JH, Alberts SR, Ashman JB, Jaroszewski DE. Cancer of the stomach and gastroesophageal junction. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 75.
National Cancer Institute website. Gastric cancer treatment (PDQ) – health professional version. www.cancer.gov/types/stomach/hp/stomach-treatment-pdq. Updated August 17, 2018. Accessed November 12, 2018.