The stomach is a muscular bag with a capacity of about 1 liter or quart. It lies along the digestive tract between the esophagus and the small intestine.
The stomach serves as a reservoir for food eaten during meals and begins the process of digestion. Its inner walls are composed of glands that secrete acid and digestive enzymes.
The most common form of cancer that affects the stomach is adenocarcinoma, which arises in the glands of the innermost layer of the stomach. This tumor tends to spread through the wall of the stomach and from there into the adjoining organs (pancreas and spleen) and lymph nodes. It can spread through the bloodstream and lymph system to distant organs (metastasize).
The incidence and death rates for stomach cancer have decreased markedly during the past 60 years. In 1930, stomach cancer was the leading cause of cancer-related deaths among American men. Since then, the death rate in men from stomach cancer in the United States has dropped from 28 to 5 per 100,000 people.
In 1996, about 22,800 new cases of stomach cancer were diagnosed in the United States, and 14,000 Americans died of the disease. This form of cancer is 1.5-2.5 times more common in African American, Hispanic, and Native American people than in whites.
Early symptoms of stomach cancer tend to be vague and nonspecific.
Seek medical attention if you have any of the following symptoms:
- Mild upper abdominal discomfort associated with nausea and loss of appetite.
- Difficulty swallowing because of a tumor involving the upper part of your stomach, near the esophagus.
- Feeling of fullness after taking only a small amount of food.
- The following symptoms may indicate advanced disease:
- Weight loss.
- Iron deficiency anemia.
- Overt blood loss.
- Vomiting blood or a material that looks like coffee grounds or passing black stools.
Severe nausea and vomiting - A late symptom caused by blockage of the stomach drainage by the enlarging cancer.
Doctors aren't sure what causes stomach cancer. There is a strong correlation between a diet high in smoked, salted and pickled foods and stomach cancer. As the use of refrigeration for preserving foods has increased around the world, the rates of stomach cancer have declined.
In general, cancer begins when an error (mutation) occurs in a cell's DNA. The mutation causes the cell to grow and divide at a rapid rate and to continue living when normal cells would die. The accumulating cancerous cells form a tumor that can invade nearby structures. And cancer cells can break off from the tumor to spread throughout the body.
Types of stomach cancer
The cells that form the tumor determine the type of stomach cancer. The type of cells in your stomach cancer helps determine your treatment options.
Types of stomach cancer include:
- Cancer that begins in the glandular cells (adenocarcinoma). The glandular cells that line the inside of the stomach secrete a protective layer of mucus to shield the lining of the stomach from the acidic digestive juices. Adenocarcinoma accounts for the great majority of all stomach cancers.
- Cancer that begins in immune system cells (lymphoma). The walls of the stomach contain a small number of immune system cells that can develop cancer. Lymphoma in the stomach is rare.
- Cancer that begins in hormone-producing cells (carcinoid cancer). Hormone-producing cells can develop carcinoid cancer. Carcinoid cancer in the stomach is rare.
- Cancer that begins in nervous system tissues. A gastrointestinal stromal tumor (GIST) begins in specific nervous system cells found in your stomach. GIST is a rare form of stomach cancer.
Because the other types of stomach cancer are rare, when people use the term "stomach cancer" they generally are referring to adenocarcinoma.
The treatment of stomach cancer depends on the results of tests and your overall health.
- People with advanced heart and lung disease may not tolerate aggressivetherapy.
- In many cases, the stomach cancer may have advanced too far for any available treatment to work.
- You will require surgery to be cured. Your stomach is removed entirely, and your esophagus is attached to your smallintestine.
- Surgery may relieve symptoms of obstruction. The upper end of your stomach is connected to your small bowel, bypassing the area of obstruction.
- Companion treatment with either chemotherapy or radiation may improve your survival following surgery.
- After your stomach has been removed, your doctor will monitor your disease with repeat CT scans of your abdomen and gastrointestinal endoscopy to make sure the cancer does not return.