Understanding stomach cancer

What is stomach cancer?

The stomach is a large J-shaped pouch that connects the esophagus, the body’s tube from the mouth, to the intestines. It is where food is partly digested before being passed to the small intestine. Stomach cancer, also known as gastric cancer, begins when abnormal cells in the lining of your stomach grow out of control.

Who gets stomach cancer?

About 27,000 people in the U.S. are diagnosed with stomach cancer every year, according to the National Cancer Institute, and about 130,000 people are living with it.

Doctors don’t know what causes stomach cancer, but they have identified risk factors that include:

• Gender: Men are more likely to develop stomach cancer. 
• Age: Stomach cancer rates increase sharply in people older than 50. 
• Infection: H. pylori, a type of bacterial infection of the stomach, can lead to inflammation and ulcers. It is found in most stomach cancer patients.
• Diet: Diets high in salted, pickled, fermented, smoked and preserved foods, including processed meats.
• Smoking
• Family history: Having a parent, sibling or child with stomach cancer.
• Genetic syndromes: Several inherited genetic defects increase the risk. OHSU offers genetic counseling, testing and risk assessment to help you identify and manage risk.
   

Survival rates for stomach cancer

A key concept in understanding survival is five-year relative survival rate. This is the percentage of people who are alive five years after they were first diagnosed, compared to the general population. (It doesn’t count death from other causes.)

The key to successful treatment is early detection. If stomach cancer is found before it has spread, the five-year relative survival rate is 75%. 

Unfortunately, stomach cancer often isn’t found until after it has spread, so overall survival rates remain discouraging.

It's important to remember that these figures are averages and can't predict the outcome for any one patient. It's also important to remember that these figures are based on the treatments that were available more than five years ago. Patients who are diagnosed now may have a better outlook. Treatments are getting better all the time.

Signs of hope: Survival rates are steadily climbing. Our Cancer Early Detection Advanced Research Center is dedicating hundreds of scientists to finding ways to detect cancer earlier.

Quality of life: Your team is devoted to helping you live longer and do the things you enjoy.

Stomach cancer symptoms

Early on, you might have no symptoms. Or you might have symptoms such as mild abdominal pain, nausea or heartburn, which rarely mean you have stomach cancer. Talk with your primary care doctor if symptoms persist.

Other signs and symptoms can include:

• Fatigue
• Feeling bloated after eating
• Feeling full after eating small amounts of food
• Severe, persistent heartburn
• Severe indigestion that doesn’t go away 
• Unexplained, persistent nausea
• Persistent vomiting
• Unexplained weight loss

Diagnosing stomach cancer

Tests at OHSU might include:

Types of stomach cancer

Stomach cancer stages

Staging helps your care team develop the most effective treatment recommendations. It measures factors such as:

• Your age and overall health.
• How many of your stomach’s layers the cancer has invaded.
• Whether cancer has spread to your lymph nodes (bean-size structures that act as filters for your immune system).
• Whether cancer has spread to other body parts, most commonly the liver.

Stomach cancer staging is very complex. This is a simple description for staging the main type of stomach cancer, an adenocarcinoma, after tissue has been directly examined. Find a detailed description at the American Cancer Society website.

Stage I: The tumor has invaded as far as the stomach’s muscle layer and has spread to as many as two nearby lymph nodes.

Stage II: Cancer has not reached the muscle layer but has spread to as many as 15 nearby lymph nodes. Or it has invaded as far as the stomach’s outer layer but to no lymph nodes. 

Stage III: The tumor has invaded as far as tissue next to the stomach and to as many as 16 or more nearby lymph nodes.

Stage IV: Cancer has spread to a distant part of the body. This stage is also called advanced or metastatic cancer.

Treatment for stomach cancer

Surgery

If cancer hasn’t spread beyond the stomach wall or nearby lymph nodes, your care team will most likely recommend removing it with surgery. This, combined with other treatments, generally offers the only path to a cure. Surgery can also relieve symptoms of advanced cancer. 

Types of stomach cancer surgery include:

• Endoscopic surgery: For early-stage cancers, your care team might be able to use endoscopy. Your doctor guides a flexible scope and tiny instruments down your throat to remove the cancer. 
• Partial gastrectomy: Your doctor removes the part of the stomach and lymph nodes affected by cancer, and possibly some surrounding tissue as well.
• Total gastrectomy: Your entire stomach, nearby lymph nodes and perhaps parts of other organs are removed. Your care team will create a new stomach pouch from your small intestine. The team will attach it to your esophagus (food pipe) to restore your digestive tract.
• HIPEC surgery: This treatment may be an option if your cancer spreads to the abdominal lining, leading to a complex condition called peritoneal surface malignancies. In HIPEC surgery, doctors remove tumors, then flood the abdominal cavity with chemotherapy medication.
• Palliative surgery for advanced cancer: Your care team can remove some of the tumor to stop bleeding and to prevent stomach openings from being blocked.
• Other surgeries: Surgery can also place a feeding tube in your stomach. Or surgeons might place a stent (metal tube) in stomach openings to hold them open so food can go through.

Chemotherapy

Chemotherapy uses medications, usually given in a slow IV drip, to attack cancer cells nearly anywhere in your body. Sometimes it’s combined with radiation therapy. With stomach cancer, it may be used:

• Before surgery (neoadjuvant chemotherapy), to shrink the tumor.
• After surgery (adjuvant chemotherapy), to kill cancer cells circulating in your body.
• For advanced cancer, to slow cancer growth and to control symptoms.

Radiation therapy

Radiation therapy uses beams of energy to target cancer cells. For stomach cancer patients, radiation is most often delivered using external beam radiation therapy, with the equipment outside your body. With stomach cancer, it may be used:

• Before surgery (neoadjuvant radiation therapy), to shrink the tumor. 
• After surgery (adjuvant radiation therapy), to kill any cancer cells that remain.
• For advanced cancer, to control symptoms such as bleeding or a stomach blockage.

Targeted therapies

Targeted therapies are drugs that lock onto receptors on cancer cells and shut them down. They can cause fewer side effects because they mostly leave healthy cells alone. They are usually pills or capsules.

Several targeted therapies are available for stomach cancer. One, Herceptin, binds to proteins on the surface of cancer cells, like a key fitting into a lock. This can block the cells from receiving chemical instructions to divide and grow, and it can instruct the cell to malfunction.

Learn more

• Look for an OHSU clinical trial for stomach cancer.
• Learn about OHSU’s expert palliative care providers to help you and your family manage stress and symptoms.
• Learn how our cancer dietitians can help you with concerns about nutrition and the effects of cancer.
• Gastric Cancer Treatment, National Cancer Institute
• Stomach Cancer, American Cancer Society
• No Stomach for Cancer, support and advocacy group