Definition

Stomach cancer is the growth of cancer cells in the stomach. The stomach is the organ in the upper belly that receives food. Different types of cancer are:

• Adenocarcinoma—tumors of the innermost layer (most common)
• Lymphoma—a cancer of the immune system, sometimes in the stomach wall
• Gastric stomal tumors—tumors of the stomach wall
• Carcinoid tumors—tumors of the hormone-producing cells of the stomach

Stomach Cancer Copyright © Nucleus Medical Media, Inc.

Causes

Cancer happens when cells divide without control or order. These cells grow together to form a tumor. They can invade and damage nearby tissues. They can also spread to other parts of the body.

It is not clear what causes changes in the cells. It is likely a combination of genes and environment.

Risk Factors

Stomach cancer is more common in men. It is also more common in people from eastern Asia, eastern Europe, and South America. Other things that may raise the risk are:

• Certain infections, such as Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV)
• Genes, or family history of stomach cancer—or certain cancer syndromes
• A diet high in:
  • Salt, salt-preserved, and pickled foods
  • Red or processed meat
• Being overweight or obese
• Smoking or alcohol use disorder
• Pernicious anemia
• Previous stomach surgery
• Ménétrier disease, or certain types of long-term gastritis

Symptoms

In some people, stomach cancer may have no symptoms. Others may have:

• Belly pain, discomfort, bloating, or fullness
• Weight loss without trying
• Loss of hunger
• Painful swallowing
• Blood in vomit or stool
• Weakness, fatigue
• Lasting nausea and vomiting
• A swelling or mass in the belly area

Diagnosis

The doctor will ask about your symptoms and medical health. A physical exam will be done.

Tests may include:

• Blood tests
• Fecal occult blood test—to test for blood in the stool
• Biopsy—a tissue sample that can be examined under a microscope

Imaging tests will be used to look for cancer or spreading of the cancer. They may include:

• Upper GI endoscopy
• CT scan
• Ultrasound
• positron emission tomography (PET) scan
• Laparoscopy

The exam and test results are used to diagnose the cancer. They are also used for staging. Staging outlines how far and fast cancer has spread.

Treatment

Cancer treatment depends on the stage and type of cancer. A combination of therapies may be used.

Options may include:

• Surgery such as:
  • Endoscopic mucosal resection—removal of the tumor through an endoscope
  • Subtotal gastrectomy—removal of the lower part of the stomach
  • Total gastrectomy—removal of the whole stomach and often nearby lymph nodes
• Radiation therapy—to kill or shrink cancer cells
• Chemotherapy given by mouth, injection, or IV—to kill cancer cells

Prevention

The risk of stomach cancer may be reduced by:

• Achieving and maintaining a healthy weight
• Treating H. pylori infection
• Eating a healthy diet, and:
  • Limiting salted, pickled, and smoked foods
  • Limiting red meat
  • Limiting alcohol
• Not smoking

Some people have a very high risk of stomach cancer due to genes. For them, stomach removal (gastrectomy) may be an option.