Stomach cancer is a malignant tumor that begins in the stomach. Men are affected more than women.
What is going on in the body?
Stomach cancer usually arises from cells that line the inside of the stomach. A cell will undergo changes that cause it to become malignant. It will begin to grow and multiply uncontrollably. The cancer cells will form a tumor.
The tumor will invade and destroy tissues around it as it grows. Eventually it can penetrate through the wall of the stomach and spread to structures around the stomach. Cancer cells can also break off from the tumor and enter the blood stream. These cells will form new tumors in other parts of the body, a process known as metastasis.
What are the causes and risks of the disease?
No one knows the precise reason why this cancer occurs. People from Japan are at higher risk than people from other areas. Risk decreases when people at risk move to areas of lower risk. This is suspected to due to changes in diet. Cancer of the stomach is higher among people who smoke and consume alcohol than in those who do not.
Risk factors for stomach cancer include:
- family history
- type A blood
- lack of stomach acid
- low socioeconomic status
- low consumption of fruits and vegetables
- consumption of salted, smoked, or poorly preserved food
- cigarette smoking
- increased age
- certain ethnic groups
What can be done to prevent the disease?
Avoiding all tobacco products will decrease the likelihood of developing stomach cancer.
A diet high in fruits and vegetables is thought to be helpful in avoiding this cancer.
Some conditions that may predispose to stomach cancer include:
chronic gastritis, which is inflammation of the stomach
Barrett's esophagus, which is chronic inflammation of the lower end of the esophagus caused by gastroesophageal reflux disease
previous stomach surgery, such as a partial gastrectomy
H. pylori infection, a bacterial infection of the stomach
certain gastric polyps, such as those that are adenomatuous
pernicious anemia, a low red blood cell count caused by vitamin B12 deficiency which in some cases may be due to an autoimmune disorder
- Menetrier's disease (or giant hypertrophic gastritis), a form of gastritis in which the stomach lining has excess folds due to thickening of the stomach wll
How is the disease diagnosed?
Usually, a person sees a healthcare provider because of a symptom such as weight loss and nausea. The provider will take an in-depth history, which includes a nutritional assessment. The first test may be an x-ray of the stomach called an upper gastrointestinal X-ray exam, or upper GI.
Depending on the results of the upper GI, the next part of the evaluation will be a flexible gastroscopy in which a long, slender and flexible tube (an endoscope) with a light on the end is passed into the stomach. This allows the physician to look at the walls of the stomach. If any of the tissue looks unusual, a biopsy will be done to remove a piece to determine if it is cancer.
If cancer is confirmed, other tests will be done to determine the extent of the disease. These tests include CT scans and other specialized x-rays. Tumor markers ( chemicals produced by tumors) are not useful in diagnosing early stage stomach cancer but may be useful to track the cancer after surgery.
Long Term Effects
What are the long-term effects of the disease?
This cancer is usually found late in the course of the disease when treatment is not likely to be effective.
What are the risks to others?
There are no risks to others.
What are the treatments for the disease?
If the disease is found early, surgery to remove all of the cancer and some surrounding tissue can be performed. Sometimes chemotherapy or radiation therapy is given before surgery to shrink the tumor. Chemotherapy and radiation are sometimes offered after surgery to help prevent recurrence. Surgery to bypass advanced cancer can relieve symptoms of nausea. Chemotherapy or radiation therapy may also shrink uncomfortable tumors in people with advanced cancers. Advanced stomach cancer is not curable.
What are the side effects of the treatments?
Removing most of the affected stomach may mean the person will have to permanently modify the diet. Many patients will experience dumping syndrome, with symptoms including sweating and weakness after eating. Small, frequent meals are recommended.
Side effects of chemotherapy are significant but manageable. The specific side effects vary according the medication given. Radiation therapy to the area can cause abdominal pain, diarrhea and increased nausea. This is generally manageable and will resolve when treatment ends.
What happens after treatment for the disease?
The person will be monitored to determine the response of the cancer to treatment. If the cancer was completely removed, the person will be monitored over time to determine if the cancer returns. If the cancer returns or progresses, different therapy can try to improve quality of life. Treatment at this point will not cure the cancer.
How is the disease monitored?
CT scans are used to monitor the spread of the disease to other organs such as the liver, and to evaluate response of the cancer to treatment.
Coia, L.R.; Bonin, S.R.; Diaz-Canton, E.A.;&Ellenhorn, J. D.I. (1996). Gastric cancer in Cancer Management: A Multidisciplinary Approach. PRR: Huntington, NY. Pp. 87-95.
Christine Miaskowski, Patricia Buchsel, 1999 Oncology Nursing: Assessment and Clinical Care. Mosby pg. 1015-1030