Key takeaways

  • Stomach cancer, or gastric cancer, develops in the stomach lining when cells grow abnormally. Risk factors include Helicobacter pylori (H. pylori) infection, smoking, family history, and regularly eating salted, pickled, or smoked foods.
  • Early symptoms may include loss of appetite, bloating, indigestion, frequent burping, and unexplained weight loss. Advanced symptoms can include bloody stool, yellowing of the skin and eyes, and swollen lymph nodes.
  • Treatment options include surgery to remove the tumor, chemotherapy, radiation therapy, targeted medications, and immunotherapy. If you experience persistent symptoms or have risk factors, talk with a healthcare professional for evaluation.

According to the World Health Organization (WHO), stomach cancer, or gastric cancer, caused 769,000 deaths worldwide in 2020. It is the fourth most common cancer worldwide and the third-leading cause of cancer-related deaths.

In the United States, the number of new stomach cancer diagnoses has fallen by around 1.5% annually for the past decade.

Around 90% to 95% of all stomach cancers are gastric carcinomas, or adenocarcinomas. In this type, cancer develops from the cells that form in the mucosa. This is the lining of the stomach that produces mucus.

This article discusses how to recognize, diagnose, and treat stomach cancer and the risk factors for developing it.

Stomach cancer symptoms can vary. At the same time, these symptoms may not appear for many years because stomach cancers can grow very slowly.

For this reason, many people with stomach cancer do not receive a diagnosis until it is already advanced.

What are the first signs of stomach cancer?

Early stage symptoms of stomach cancer may mimic other conditions, such as stomach ulcers. They include:

  • appetite loss
  • a sensation of being full after eating small amounts
  • bloating after meals
  • dark stool
  • feeling sick
  • indigestion that does not resolve and burping
  • stomach ache
  • swallowing difficulties
  • tiredness from anemia
  • unexplained weight loss

Many of these symptoms are very similar to those of other, less serious conditions. However, anyone with an increased risk for stomach cancer who experiences swallowing difficulties should seek prompt medical treatment.

As stomach cancer becomes more advanced, people may experience some of the early signs alongside the following symptoms.

What are the advanced symptoms of stomach cancer?

  • a buildup of fluid in the stomach, which may cause the stomach to feel lumpy to the touch
  • black stool that contains blood
  • blockage in the small bowel
  • constipation
  • itchy skin
  • persistent cough or chest infection
  • shortness of breath
  • swollen lymph nodes
  • yellowing of the skin and eye whites from jaundice

While it is not always clear what causes stomach cancer to develop, certain factors may increase the risk of developing this cancer. These include medical conditions such as:

  • H. pylori infection in the stomach
  • atrophic gastritis (long-term stomach inflammation that makes the stomach lining thinner)
  • hypertrophic gastropathy (excess growth of the stomach lining, resulting in lowered levels of stomach acid)
  • pernicious anemia, which can develop due to a deficiency of vitamin B12
  • adenomatous stomach polyps

Certain genetic conditions also add to the risk of stomach cancer, including:

  • familial adenomatous polyposis (FAP)
  • familial intestinal gastric cancer
  • hereditary diffuse gastric cancer
  • Li-Fraumeni syndrome
  • Lynch syndrome
  • Peutz-Jeghers syndrome
  • type A blood

Additional factors that can raise the risk of stomach cancer include:

  • Smoking: Regular, long-term smokers have a greater risk of stomach cancer than nonsmokers.
  • Family history: Having a close relative who has had stomach cancer can increase the risk.
  • Diet: People who regularly eat salted, pickled, or smoked foods have a higher risk of developing gastric cancer. Regularly eating charcoaled, grilled, or processed meats can also increase the risk. A high intake of red meat and refined grains may also increase the risk. Low intake of fresh fruits and vegetables can also impact risk.
  • Age: The risk of developing stomach cancer increases significantly after the age of 50 years. According to the American Cancer Society (ACS), 60% of people who receive a stomach cancer diagnosis are at least 65 years old.
  • Sex: Men are more likely to get stomach cancer than women.
  • Excess weight: Having overweight or obesity can increase the risk of cancer that affects the upper stomach, near the esophagus.
  • Surgeries: Previous surgery to the stomach or a part of the body that affects the stomach, such as ulcer treatment, can increase the risk of stomach cancer years later.

People who experience symptoms and have one or more of these risk factors should contact a doctor for evaluation.

Treatment for stomach cancer depends on several factors, including the severity of the person’s cancer and the individual’s overall health and preferences.

Treatment options include:

  • Surgery: Doctors may need to surgically remove the stomach cancer as well as a margin of healthy tissue. Possible types of surgery include endoscopic mucosal resection, subtotal gastrectomy, and total gastrectomy. In some cases, palliative surgery may also be necessary to help prevent or ease stomach cancer symptoms and complications.
  • Radiation therapy: A specialist uses radioactive rays to target and kill cancerous cells. This type of therapy is not common in stomach cancer treatment. However, it may be necessary if the cancer is advanced or causes severe symptoms or as a way to help shrink the stomach tumor before surgery.
  • Chemotherapy: This treatment uses drugs that stop rapidly growing cancer cells from dividing and multiplying. Chemotherapy is a primary treatment for stomach cancer that has spread to distant sites in the body. A cancer care team may also administer chemotherapy to shrink the tumor before surgery or kill the remaining cancer cells after surgery.
  • Targeted medications: These therapies recognize and attack specific proteins that cancer cells produce. Targeted therapy can be administered in combination with chemotherapy or on its own.
  • Immunotherapy: This treatment uses medication to encourage the body’s immune cells to attack cancer cells. People with advanced stomach cancer who have received two or more other treatments are candidates for immunotherapy.

Individuals with persistent symptoms of stomach cancer should contact a doctor as soon as possible.

The doctor will ask about their symptoms, family history, and medical history, as well as lifestyle choices, such as what they eat and drink and whether they smoke. They will also perform a physical examination to check for stomach tenderness or lumpiness.

They may also perform blood tests to identify whether there is an excess of certain substances that indicate cancer, including a complete blood count (CBC) to measure the number of red and white blood cells, as well as platelets and hemoglobin.

If the doctor suspects stomach cancer, they will refer a person to a specialist in stomach diseases for tests. This specialist is known as a gastroenterologist.

Diagnostic measures include:

  • upper endoscopy
  • CT scan
  • barium swallow
  • biomarker testing

There is no way to prevent stomach cancer entirely.

However, a person can take steps to help reduce the risk of developing the disease. Where applicable, these include:

Making dietary changes

Several dietary measures can help reduce the risk of stomach cancer.

The ACS recommends eating a variety of colorful vegetables and fruits (particularly citrus varieties) every day to help limit the risk.

Reducing the quantity of pickled, salted, and smoked foods in the diet is also suggested. Switching out refined grains for whole grain cereals, bread, and pasta and replacing red or processed meats with beans, fish, and poultry may also reduce a person’s chance of developing stomach cancer.

Quitting smoking

Smoking tobacco may increase the risk of cancer developing in the part of the stomach near the esophagus.

Those who smoke should seek advice on quitting. It is advisable for people who do not already smoke to avoid exposure to tobacco smoke.

Taking nonsteroidal anti-inflammatory drugs (NSAIDs)

NSAIDs, such as aspirin, naproxen, or ibuprofen, may reduce the risk of stomach cancer. However, they carry additional risks, such as life threatening internal bleeding.

People should only take NSAIDs to treat other conditions, such as arthritis. It is important not to take them solely to reduce the risk of stomach cancer.

Testing for other conditions and cancers

Individuals who have hereditary diffuse gastric cancer syndrome and Lynch syndrome have a drastically increased risk of stomach cancer. Recognizing these and taking precautions after receiving a doctor’s advice can reduce the risk.

People with close family members who have had stomach cancer and those who had invasive lobular breast cancer before the age of 50 years may benefit from genetic testing.

If a test shows changes in the CDH1 gene, a doctor may recommend removing the stomach before cancer develops.

Researchers are actively looking into the possible cancer links of chronic H. pylori infection in the stomach lining. Early studies suggest that treating H. pylori infection with antibiotics may reduce the risk of stomach cancer, although further research is necessary.

Here are some common questions about stomach cancer.

What is the stomach cancer survival rate?

Overall, stomach cancer has a 5-year relative survival rate of 36%. This means that people with stomach cancer are 36% as likely, on average, to survive for 5 years after diagnosis as people who do not have stomach cancer.

However, this number can vary based on the stage of the cancer when a person receives a diagnosis. For example, a local stomach cancer diagnosis has a 75% relative survival rate, whereas metastatic diagnoses have only a 7% relative survival rate.

How fast does stomach cancer spread?

Stomach cancer generally grows slowly. It can take years to develop. The rate of spread can vary from person to person, depending on factors such as exact cancer type, tumor size, and location.

What is the difference between stomach cancer in females vs. males?

A person’s sex will not influence the symptoms of stomach cancer. However, men are more likely to develop it than women.

The outlook after receiving a stomach cancer diagnosis is generally unfavorable. The relative 5-year survival rate reduces as cancer becomes more aggressive and spreads beyond the original stomach tumor.

If cancer metastasizes into deeper tissues in the stomach, this rate falls to 36%. Once the stomach cancer reaches distant organs, the survival rate drops to 7%. For this reason, early diagnosis is key to improving the outlook for people with stomach cancer.

Stomach cancer, or gastric cancer, develops in the stomach lining. It often presents with vague early symptoms such as indigestion, bloating, and fullness.

This type of cancer is most effectively treated when caught early. Understanding risk factors and timely medical evaluation are key.