by Jason Wasserman MD PhD FRCPC
December 16, 2022
A hyperplastic polyp is a non-cancerous growth that develops from the tissue that lines the inside of the stomach. Another name for this growth is an inflammatory polyp.
Most hyperplastic polyps in the stomach are associated with a condition called chronic gastritis or prolonged inflammation in the stomach. The most common causes of chronic gastritis are infection of the stomach with Helicobacter pylori, bile reflux, and autoimmune gastritis.
It is very rare for cancer to develop in a hyperplastic polyp.
This diagnosis is usually made after part or all of the polyp is removed during a procedure called endoscopy. This procedure involves using a camera attached to a long tube to see the inside of the stomach. The tissue removed is then sent to a pathologist for examination under the microscope.
When examined under the microscope, hyperplastic polyps show an increased number of foveolar cells which makes the epithelium look disorganized. Large open or dilated spaces may also develop. The connective tissue or stroma surrounding the foveolar cells usually shows signs of inflammation including an increased number of inflammatory cells such as plasma cells, lymphocytes, and neutrophils.
Because hyperplastic polyps can be caused by infection of the stomach with a bacteria called Helicobacter pylori, your pathologist may perform tests such as special stains or immunohistochemistry to look for the bacteria in the tissue sample. Both of these tests make it easier to see the bacteria which are very small and difficult to see on a hematoxylin and eosin-stained (H&E) slide.