Stomach Cancer

According to the American Cancer Society, an estimated 24,590 new cases of stomach cancer were diagnosed in this country in 2015. Most cases are in people over age 65.

Stomach cancer, also called gastric cancer, has become much less common in the United States and Europe over the past 60 years. While the rates of stomach cancer in general are declining, cancers in the area of the stomach near where it joins the esophagus are increasing.

While stomach cancer is becoming less common in this country, it is the second leading cause of cancer death in much of the rest of the world, especially Japan, Eastern Europe, South America and parts of the Middle East. This may be due to differences in diet, the rate of infection with Helicobacter pylori (a type of bacteria) and the environment.

Stomach Cancer Anatomy

Many times, people refer to the abdomen, the area between the hips and chest, as the stomach. But in medical terms, the word stomach refers only to the organ.

The stomach, a J-shaped organ, is in the upper abdomen. After you chew and swallow food, it moves through a hollow tube called the esophagus into the stomach. The stomach mixes the food with gastric juices and begins digestion of the food.

The lining of the stomach has three main layers:

• Mucosal (inner)
• Muscularis (middle)
• Serosal (outer)

Generally, stomach cancer starts when cells in the mucosal layer change. Sometimes these changes develop into cancer, but most times they do not. Stomach cancer usually grows slowly and may not show symptoms for many years.

Types of Stomach Cancer

Most stomach cancers are adenocarcinomas, which develop in the cells of the mucosa. However, stomach cancer can develop anywhere in the organ and spread to other parts of the body by growing beyond the stomach wall, entering the bloodstream or reaching the lymphatic system.

The other types of cancer found in the stomach are considered rare. They include:

• Lymphoma, which affects a body’s immune system
• Gastrointestinal stromal tumors, often called GIST or gastric sarcomas
• Carcinoid tumors, which affect the hormone-producing cells of the stomach
  

Stomach Cancer Risk Factors

Although the exact cause of stomach cancer is not known, certain factors seem to increase your risk of developing the disease. These include:

• Eating foods preserved through pickling, salting and drying or that contain nitrates
• Eating foods that have not been stored or prepared correctly
• Obesity: Men who are obese have a higher risk of cancer in the part of the stomach nearest the esophagus.
• Infection with Helicobacter pylori: This type of bacteria, or germ, is a common cause of ulcers and may cause chronic inflammation in the stomach lining. This sometimes develops into pre-cancerous changes and cancer.
• Tobacco and alcohol abuse: Smoking and drinking excessive amounts of alcohol appear to increase the likelihood of cancer in the upper part of the stomach. Some studies have shown that smoking doubles the risk of stomach cancer.

Family history. If close relatives have any of the following conditions, you may be at a higher risk of stomach cancer:

• Stomach cancer
• Hereditary non-polyposis colon cancer (HNPCC)
• Li-Fraumeni syndrome

Having any of the following medical conditions: 

• Pernicious anemia
• Chronic stomach inflammation and intestinal polyps
• Menetrier disease
• Epstein-Barr virus
• Acid reflux or chronic indigestion
• Stomach lymphoma
• Type A blood
• Prior stomach surgery

Other factors include:

• Gender: The majority of stomach cancer patients are male.
• Age: Most individuals who develop stomach cancer are older than 55.
• Ethnicity: In the United States, stomach cancer occurs more often in Hispanic Americans and African Americans than in non-Hispanic whites. It is found most in Asian/Pacific Islanders.
• Working in the rubber, metal, coal and timber industries, as well as those who have been exposed to asbestos fibers, have a higher risk for stomach cancer
• Geography: More people in Japan, China, Southern and Eastern Europe, and Central and South America develop stomach cancer than those in Northern and Western Africa, South Central Asia and North America.

Not everyone with risk factors gets stomach cancer. However, if you have risk factors, you should discuss them with your doctor.

Behavioral and lifestyle changes can help prevent stomach cancer. Visit our prevention and screening section to learn how to manage your risk.

In rare cases, stomach cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Visit our genetic testing page to learn more.

Stomach cancer often does not have symptoms in the early stages. When signs do appear, they may be mistaken for less serious problems such as indigestion or heartburn. This means stomach cancer often is not found until it spreads.

Stomach cancer symptoms may include:

• Abdominal pain or discomfort
• Loss of appetite
• Heartburn, indigestion or ulcer-type symptoms
• Nausea and vomiting
• Bloating or swelling in the abdomen
• Diarrhea or constipation
• Feeling of fullness after eating small amounts of food
• Bloody or black stools
• Fatigue
• Unintentional weight loss

These symptoms do not always mean you have stomach cancer. However, if you notice any of them for more than two weeks, talk to your doctor. Even if they are not signs of cancer, they may signal other health problems.

Behavioral and lifestyle changes can help prevent stomach cancer. Visit our prevention and screening section to learn how to manage your risk.

In rare cases, stomach cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Visit our genetic testing page to learn more.

Because stomach cancer often does not have symptoms until it has spread to other parts of the body or has symptoms that are mistaken for other conditions, it can be challenging to diagnose.

However, it is important for stomach cancer to be diagnosed as soon and as accurately as possible. This helps increase your odds for successful treatment and lowers the chance of side effects.

The experts at MD Anderson are among the most skilled and experienced in diagnosing and staging stomach cancer. They use specialized advanced technology with pinpoint focus and reliable outcomes.

Precise Diagnostic Tools

In addition to standard diagnostic procedures, MD Anderson offers endoscopic ultrasound, which gives specially trained doctors the ability to look inside the stomach and examine its walls for stomach cancer or pre-cancerous changes. This test, which is not available at many cancer centers, also allows physicians to view and biopsy the lymph nodes around the stomach.

Because stomach cancer can spread inside the abdomen and often is not detectable by any other means, specialists at MD Anderson often perform staging laparoscopies, which are minimally invasive procedures to see if tumors have spread in abdomen.

Researchers at MD Anderson were involved in recent studies to differentiate between gastrointestinal stromal tumor (GIST) and leiomyosarcoma (LMS) with near perfect accuracy. This will have wider application in more individualized diagnosis and treatment of stomach cancer and other types of cancer.

Stomach Cancer Diagnostic Tests

If you have symptoms that may signal stomach cancer, your doctor will examine you and ask you questions about your health, your lifestyle, including smoking and drinking habits, and your family medical history.

If stomach cancer is suspected, early tests may include:

• X-rays of the gastrointestinal tract
• Testing a stool sample for traces of blood

In addition, one or more of the following tests may be used to find out if you have stomach cancer, if it has spread or if treatment is working.

Biopsy: A biopsy is the removal of tissue to examine under a microscope. Different methods are available to obtain the tissue, depending on where it is located. In stomach cancer, biopsies usually are performed by endoscopy. An endoscope is inserted through the mouth, nose or an incision into the esophagus and stomach. The endoscope has a tool to remove tissue samples for examination.

Imaging tests, which may include:

• CT or CAT (computed axial tomography) scans
• PET (positron emission tomography) scans
• MRI (Magnetic resonance imaging)
• Chest and dental X-rays

Endoscopic ultrasound: Using specialized equipment, doctors insert an endoscope equipped with a small ultrasound device into the stomach. It produces sound waves that produce an image on a video screen.

Barium swallow: Also called an upper GI (gastrointestinal) series, this set of X-rays of the esophagus and stomach may be used to look for stomach cancer.

Blood tests, which may include:

• Complete blood count (CBC) to look for anemia (low level of red blood cells) that may be caused by internal bleeding
• β-hCG (beta-human chorionic gonadotropin), CA-125 and CEA(carcinoembryonic antigen) assays that measure certain chemicals in the blood

Behavioral and lifestyle changes can help prevent stomach cancer. Visit our prevention and screening section to learn how to manage your risk.

In rare cases, stomach cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Visit our genetic testing page to learn more.

Stomach Cancer Staging

If you are diagnosed with stomach cancer, your doctor will determine the stage of the disease.

Staging is a way of classifying cancer by how much disease is in the body and where it has spread when it is diagnosed. This helps the doctor plan the best way to treat the cancer.

Once the staging classification is determined, it stays the same even if treatment is successful or the cancer spreads.

Stomach Cancer Stages

(source: National Cancer Institute)

Stage 0: Abnormal cells are found in the inside lining of the mucosal (innermost) layer of the stomach wall. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.

Stage 1: Stomach cancer has formed. Stage 1 is divided into stage 1A and stage 1B, depending on where the cancer has spread.

Stage 1A: Cancer has spread completely through the mucosal (innermost) layer of the stomach wall.

Stage 1B: Cancer has spread to either:

• Completely through the mucosal (innermost) layer of the stomach wall and is found in up to six lymph nodes near the tumor
• The muscularis (middle) layer of the stomach wall

Stage 2: Stomach cancer has spread to one of the following:

• Through the mucosal (innermost) layer of the stomach wall and to seven to 15 lymph nodes near the tumor
• The muscularis (middle) layer of the stomach wall and to up to six lymph nodes near the tumor
• The serosal (outermost) layer of the stomach wall but not to lymph nodes or other organs

Stage 3 is divided into stage 3A and stage 3B depending on where the cancer has spread:

Stage 3A: Stomach cancer has spread to the:

• Muscularis (middle) layer of the stomach wall and seven to 15 lymph nodes near the tumor
• Serosal (outermost) layer of the stomach wall and one to six lymph nodes near the tumor
• Organs next to the stomach but not to lymph nodes or other parts of the body

Stage 3B: Stomach cancer has spread to the serosal (outermost) layer of the stomach wall and seven to 15 lymph nodes near the tumor.

Stage 4: Stomach cancer has spread to one of the following:

• Organs next to the stomach and to at least one lymph node
• More than 15 lymph nodes
• Other parts of the body

Our Treatment Approach

At MD Anderson, we customize your stomach cancer treatment to ensure the highest chances for successful treatment while focusing on your quality of life. Our treatments include targeted and gene therapies, laser therapy and minimally invasive surgery.

Since stomach cancer treatment often involves more than one type of therapy, your personalized course of treatment is planned by a group of experts that may include oncologists, radiation oncologists and surgeons. This team approach – coupled with extraordinary skill and the latest technology – means you receive the best possible care with the least impact on your body.

MD Anderson's skilled surgeons and specialized procedures to treat stomach cancer are focused on helping you retain as much of the stomach as possible. However, if surgical removal of part or all of the stomach is unavoidable, we have the skill and staff to help you cope.

Stomach Cancer Treatments

If you are diagnosed with stomach cancer, your doctor will discuss the best options to treat it. This depends on several factors, including the type and stage of the cancer, the location of the tumor and your general health.

One or more of the following therapies may be recommended to treat the cancer or help relieve symptoms.

Surgery

Surgery is the most common treatment for stomach cancer, many times with chemotherapy and radiation. If all three therapies are needed, MD Anderson’s standard approach is to give chemotherapy and radiation before surgery. This method usually is more successful and better tolerated.

Stomach cancer surgery is delicate and challenging, and it requires special expertise. Studies have shown that patients do better when their surgeons have a high level of experience, and MD Anderson surgeons are among the most experienced in the country.

Surgical techniques for stomach cancer may include:

Endoscopic mucosal resection: An endoscope is inserted down the throat and into the stomach, allowing doctors to remove certain types of early, non-invasive stomach cancers.

Subtotal (partial) gastrectomy: The cancerous part of the stomach, nearby lymph nodes (tissues that filter infection and disease) and parts of other organs near the tumor are surgically removed.

Total gastrectomy: The entire stomach, nearby lymph nodes and sometimes the spleen, parts of the esophagus, intestines, pancreas and other organs where the cancer has spread, are removed. The esophagus is reconnected to the small intestine you can continue to eat and swallow.

During the surgery, the surgeon forms a new “stomach” from part of the intestine. After surgery, you may:

• Have a feeding tube that goes directly into your small intestine to be sure you receive needed nutrients
• Need to eat smaller, more frequent meals and avoid sugar
• Have abdominal discomfort and diarrhea
• Need to take vitamin supplements as pills or shots (injections)

If a stomach cancer tumor is blocking the stomach but cannot be removed completely, surgery may be done to help you eat normally. Procedures include:

• Endoluminal stent placement: A thin, expandable tube is placed between the stomach and esophagus or small intestine to keep the passageway open.
• Endoluminal laser therapy: An endoscope with a laser is inserted into the body. The laser cuts the tumor.

Chemotherapy: At MD Anderson, chemotherapy for stomach cancer often is given before surgery to shrink the tumor. MD Anderson offers the most advanced chemotherapy regimens with the fewest side effects.

Radiation therapy: We use the most precise methods of radiation therapy, targeting the stomach cancer while limiting damage to surrounding areas.

Targeted therapies: These agents are specially designed to treat stomach cancer’s specific genetic and molecular profile to help your body fight the disease.

Gene therapy: We have the expertise to examine each tumor carefully to determine gene-expression profiles, which then guide us toward the most effective, gentlest treatment targeted to your specific cancer. Gene therapy is a personalized medicine approach that sets us above and beyond most cancer centers and allows us to attack the specific causes of each stomach cancer.

Our Stomach Cancer Clinical Trials

Since MD Anderson is one of the nation’s leading research centers, we’re able to offer clinical trials (research studies) of new treatments for every type and stage of stomach cancer.