H. pylori can cause ulcers, lead to cancer screening
Q: I was having stomach pain and some nausea. The doctor found bacteria in my stomach, and I was diagnosed with a gastric ulcer. Now I'm being told that I should get screened for stomach cancer. Is that really necessary? If I agree, what are the tests I will need to get?
A: The word ulcer refers to an open wound that is failing to heal within a reasonable timeframe. Ulcers can occur on the surface of the skin and can develop within the digestive tract. The most common are gastric and peptic ulcers. The former are located in the stomach, while the latter include damage to the first section of the small intestine.
A common cause of both gastric and peptic ulcers is infection with Helicobacter pylori. Often shortened to H. pylori, it is a spiral-shaped bacterium that can, as it burrows into the stomach lining, give rise to inflammation. This, in turn, can weaken the protective lining that shields the stomach from the corrosive effects of gastric juices. Over time, this exposure can lead to the open wounds in the stomach lining that are known as ulcers.
Symptoms of gastric ulcers include the stomach pain and nausea that you experienced. Additional symptoms include loss of appetite, abdominal discomfort or bloating that grows worse after eating and a sensation of feeling full even after eating only small portions.
An ulcer that is severe can cause abdominal bleeding. When this occurs, the affected person often notices that their stools have become tarry and can range in color from bright red to a dark brown or black.
The majority of stomach ulcers do not indicate the presence of cancer. However, the two diagnoses do share a significant overlap in symptoms. Research shows that people with stomach cancer often also have an H. pylori infection. For those reasons, patients who have been diagnosed with a gastric ulcer are often urged to undergo screening for stomach cancer as well.
Additional risk factors for stomach cancer include being a smoker, being overweight and having a family history of the disease. If any of those apply to you, they may play a role in the screening recommendation.
The screening you have been advised to have often includes an upper endoscopy. This is a test that uses a thin tubelike instrument, known as an endoscope, to examine the lining of the stomach and the start of the small intestine. The endoscope, which is tipped with a tiny light and a lens, is inserted through the mouth and guided down the esophagus into the stomach. It may also be equipped with a surgical tool to capture a bit of tissue to be examined under a microscope.
To ease discomfort, many people opt to be sedated during an endoscopy. It can range from minimal, in which the person feels relaxed and drowsy, to deep sedation, in which they are asleep.
Cancers that are caught early often have better outcomes. We urge you to talk to your doctor about the pros and cons of a cancer screening and about the reasons you are hesitant.
• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.
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