Yes, growths can form on the inner lining of the stomach, a condition referred to as gastric polyps. These growths are a relatively common incidental finding during an upper endoscopy. While the presence of polyps can be concerning, most are benign and do not carry a significant risk of turning into cancer.
Defining Gastric Polyps
A gastric polyp is an abnormal growth of tissue that projects from the stomach’s mucosal or submucosal layer into the lumen. The term “polyp” describes the shape of the growth, which can be attached by a stalk or be a broader, flatter elevation. After removal, the polyp’s structure is examined through histology to determine its specific type and potential for malignancy. Gastric polyps are a descriptive finding that encompasses a wide range of underlying causes and tissue characteristics.
Understanding the Major Types
The significance of a gastric polyp depends entirely on its specific cellular makeup. Three main types account for the majority of gastric polyps, and each carries a different level of malignant potential. Understanding these differences is central to determining the necessary management and surveillance plan.
Fundic Gland Polyps (FGP)
Fundic gland polyps (FGPs) are the most frequently encountered type of gastric polyp. They are typically small, multiple, and found in the upper sections of the stomach, such as the fundus and body. These polyps have a very low potential for malignant transformation.
FGPs are frequently associated with the long-term use of proton pump inhibitor (PPI) medications, which are prescribed for acid reflux and peptic ulcers. If the polyps are sporadic and small, monitoring is usually sufficient. However, a larger FGP greater than 1 centimeter may warrant removal.
Hyperplastic Polyps (HP)
Hyperplastic polyps (HP) are the second most common type and are a reactive response to chronic inflammation or tissue irritation in the stomach lining. They are strongly linked to chronic gastritis, particularly that caused by infection with Helicobacter pylori bacteria. These polyps can appear anywhere in the stomach but are often found near areas of inflammation.
While mostly benign, HPs carry a moderate risk of progression to cancer, especially if they are larger than 1 centimeter. Eradicating the underlying H. pylori infection with antibiotics often causes these polyps to shrink or disappear completely.
Adenomas (Adenomatous Polyps)
Gastric adenomas are the least common type, but they are the most significant because they possess a high potential for malignant transformation. These polyps are characterized by cellular abnormality called dysplasia, and their risk of progression to cancer increases with their size. They are often found in the lower part of the stomach, known as the antrum.
Adenomas usually arise in a stomach lining already affected by chronic inflammation or intestinal metaplasia. Due to their nature, they are generally removed upon detection, regardless of size. Finding an adenoma prompts a more intensive surveillance schedule to check for recurrence or other concerning lesions.
Signs of Polyps and Risk Factors
Most gastric polyps are asymptomatic, meaning they do not cause any noticeable symptoms and are discovered incidentally during an upper endoscopy performed for other complaints. This incidental discovery is common because the polyps typically grow slowly and remain small.
When symptoms do occur, they are often non-specific and usually relate to larger polyps or those that have developed an ulceration. Symptoms can include abdominal pain, nausea, and gastrointestinal bleeding. Chronic, slow bleeding from a polyp can lead to iron-deficiency anemia, which may be the first indication of a problem.
The formation of gastric polyps is tied to factors that cause chronic irritation or inflammation of the stomach lining. The most common risk factor is infection with H. pylori bacteria, which leads to chronic gastritis. Long-term use of proton pump inhibitors is also a primary driver for the development of certain polyps.
Genetic predisposition is another cause, although it is much rarer. Inherited syndromes, such as Familial Adenomatous Polyposis (FAP), cause many polyps to form throughout the digestive tract, including the stomach. These genetic polyps carry an elevated risk of cancer and require specialized monitoring.
Treatment and Long-Term Surveillance
The medical management of a gastric polyp is determined by its type, size, and the presence of cellular dysplasia. Polyps identified as adenomas, or any polyp larger than 1 centimeter, are typically removed due to the increased risk of malignancy. This removal is usually performed during the endoscopy procedure itself, using endoscopic polypectomy.
Small, asymptomatic Fundic Gland Polyps not associated with a genetic syndrome often do not require removal. Instead, a strategy of surveillance is adopted, monitoring the polyps periodically with follow-up endoscopies. If the underlying cause of a hyperplastic polyp is an H. pylori infection, antibiotic treatment is initiated, which can lead to the regression of the polyp.
For individuals with high-risk polyps, such as adenomas or those associated with FAP, a schedule of regular follow-up endoscopy is necessary. This surveillance plan is tailored to the individual risk, ensuring that any new or recurring polyps are detected early to prevent progression to invasive cancer.