Stomach polyps — also called gastric polyps — are masses of cells that form on the lining inside your stomach. These polyps are rare and usually don't cause any signs or symptoms.

Stomach polyps are most often discovered when your doctor is examining you for some other reason.

Most stomach polyps don't become cancerous. But certain types can increase your risk of stomach cancer. Depending on the type of stomach polyp you have, treatment might involve removing the polyp or monitoring it for changes.

Stomach polyps usually don't cause signs or symptoms.

But as a stomach polyp enlarges, open sores (ulcers) can develop on its surface. Rarely, the polyp can block the opening between your stomach and your small intestine.

Signs and symptoms include:

• Pain or tenderness when you press your stomach
• Nausea
• Blood in your stool
• Anemia

When to see a doctor

See your doctor if you have persistent blood in your stool or other signs or symptoms of stomach polyps.

Stomach polyps form in response to damage to your stomach lining. The most common causes of stomach polyps are:

• Chronic stomach inflammation. Also known as gastritis, this condition can cause the formation of hyperplastic polyps and adenomas. Hyperplastic polyps are unlikely to become cancerous, although those larger than about 2/5 inch (1 centimeter) carry a greater risk.

  Adenomas are the least common type of stomach polyp but the type most likely to become cancerous. For that reason, they are generally removed.

• Familial adenomatous polyposis. This rare, inherited syndrome causes certain cells on the stomach's inner lining to form a specific type of polyp called fundic gland polyps. When associated with this syndrome, fundic gland polyps are removed because they can become cancerous. Familial adenomatous polyposis can also cause adenomas.

• Regular use of certain stomach medications. Fundic gland polyps are common among people who regularly take proton pump inhibitors to reduce stomach acid. These polyps are generally small and aren't a cause for concern.

  Fundic gland polyps with a diameter larger than about 2/5 inch (1 centimeter) carry a small risk of cancer, so your doctor might recommend discontinuing proton pump inhibitors or removing the polyp or both.

Factors that increase your chances of developing stomach polyps include:

• Age. Stomach polyps are more common among people in midadulthood to late adulthood.
• Bacterial stomach infection. Helicobacter pylori (H. pylori) bacteria are a common cause of the gastritis that contributes to hyperplastic polyps and adenomas.
• Familial adenomatous polyposis. This rare, inherited syndrome increases the risk of colon cancer and other conditions, including stomach polyps.
• Certain medications. Long-term use of proton pump inhibitors, which are medications used to treat gastroesophageal reflux disease, has been linked to fundic gland polyps.

Tests and procedures used to diagnose stomach polyps include:

• Endoscopy, to view the inside of your stomach with a scope
• Tissue sample (biopsy), which can be removed during endoscopy and analyzed in the laboratory

Treatment depends on the type of stomach polyps you have:

• Small polyps that aren't adenomas. These polyps might not require treatment. They typically don't cause signs and symptoms and only rarely become cancerous. Your doctor might recommend periodic monitoring so that growing polyps or ones that cause signs and symptoms can be removed.
• Large stomach polyps. These might need to be removed. Most stomach polyps can be removed during endoscopy.
• Adenomas. These polyps can become cancerous and are usually removed during endoscopy.
• Polyps associated with familial adenomatous polyposis. These are removed because they can become cancerous.

Your doctor will likely recommend follow-up endoscopy to check for recurring polyps.

Treating H. pylori infection

If you have gastritis caused by H. pylori bacteria in your stomach, your doctor will likely recommend treatment with a combination of medications, including antibiotics. Treating an H. pylori infection can make hyperplastic polyps disappear and might also stop polyps from recurring.

You might start by seeing your primary care doctor or you might be referred to a doctor who specializes in the digestive system (gastroenterologist).

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:

• Your symptoms, including any that seem unrelated to the reason for your appointment, and when they began
• Key personal information, including major stresses, recent life changes and family medical history
• All medications, vitamins or other supplements you take, including the doses
• Questions to ask your doctor

Take a family member or friend along, if possible, to help you remember the information you're given.

For stomach polyps, some questions to ask your doctor include:

• What's likely causing my symptoms?
• What tests do I need?
• What's the best course of action?
• I have these other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?
• Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you questions about your symptoms, such as:

• Have your symptoms been continuous or occasional?
• How severe are your symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, seems to worsen your symptoms?
• Do you have a personal or family history of colon cancer, polyps or familial adenomatous polyposis?
• Do you take medications to reduce stomach acid?