Inflammatory Polyp of the Large Intestine: Understanding Your Pathology Report

by Jason Wasserman MD PhD FRCPC
August 28, 2026

An inflammatory polyp is a non-cancerous growth on the inner lining of the colon or rectum. It forms in response to injury or inflammation. It is not cancer, it is not precancerous, and finding one does not mean cancer is present.

These polyps develop when the colon lining is damaged repeatedly, and the tissue grows outward into a raised bump as it heals. Your report may call the same growth a pseudopolyp or a post-inflammatory polyp, and all three names mean the same thing.

The prefix pseudo means false, and it is used because this growth is not a true tumor. An inflammatory polyp forms from healing tissue rather than abnormally dividing cells. This article explains what your report may say about one, and what the finding means for your follow-up.

Is an inflammatory polyp cancer?

No. An inflammatory polyp is benign, which means it is neither cancer nor precancerous. It will not turn into cancer and it does not spread.

This sets it apart from most other colon polyps. A tubular adenoma or a sessile serrated lesion is precancerous, because each is made of abnormal cells that could change into cancer over many years. An inflammatory polyp is ordinary healing tissue and carries no such risk.

What matters more than the polyp itself is the condition that produced it, and that is where most of the discussion with your doctor will focus.

What causes an inflammatory polyp?

An inflammatory polyp forms when the colon lining is injured repeatedly, and the tissue grows outward as it repairs itself. Several conditions can start this process:

Inflammatory bowel disease. This is the most common setting. People with ulcerative colitis or Crohn’s disease often develop these polyps in areas that have been inflamed for a long time.
Infection. Some bacterial, viral, or parasitic infections irritate the lining enough to produce inflammatory polyps. These usually resolve once the infection is treated.
Diverticular disease. Diverticula are small pouches that form in the colon wall. Inflammation around them can produce polyps in the nearby tissue.
Reduced blood flow. When part of the colon does not get enough blood, the lining is damaged and heals in the same outward-growing way.
Radiation therapy. Radiation aimed at the abdomen or pelvis can injure the colon lining and lead to polyp formation.
Mechanical irritation. Repeated straining or prolapse of the lining, most often low in the rectum, can produce a polyp through the same healing response. Your report may describe this as prolapse-type change.

Whatever the cause, an inflammatory polyp signals past or ongoing injury rather than a disease in its own right.

What are the symptoms of an inflammatory polyp?

Many inflammatory polyps cause no symptoms and are found incidentally during a colonoscopy for another reason.

When symptoms do occur, they usually come from the underlying condition rather than from the polyp. They may include diarrhea or loose stools, mucus in the stool, rectal bleeding, abdominal cramping, or a feeling that the bowel has not emptied completely. Bleeding is more likely when the polyp’s surface is worn away.

A large inflammatory polyp occasionally blocks part of the bowel, but this is uncommon.

How is the diagnosis made?

An inflammatory polyp is usually visible during a colonoscopy. It projects outward from the lining and can be seen directly through the camera. It is normally removed during the same procedure, either with a wire loop during a polypectomy or with biopsy forceps for smaller polyps.

The tissue is then sent to a pathologist, who examines it under a microscope. The pathologist sees inflammation and repair rather than abnormal cell growth. The glands that line the colon are still present and still recognizable, but they are surrounded by large numbers of immune cells. The pathologist also confirms that no precancerous or cancerous changes are present.

Removing the polyp both confirms the diagnosis and treats it. Because the polyp is benign, no follow-up imaging is needed.

Microscopic findings

Your report may list some of the findings the pathologist saw in an inflammatory polyp. These describe injury and healing, not cancer.

Inflammation. Large numbers of immune cells sit between the glands. These often include neutrophils and plasma cells. Their presence reflects an active response to injury.
Reactive changes. The glands may look slightly distorted or irregular. Pathologists call this reactive, meaning the cells have changed in response to nearby inflammation. It is not a precancerous change.
Granulation tissue. This is healing tissue made of new small blood vessels and inflammatory cells. It replaces some of the normal glands in larger polyps and is a normal part of repair.
Erosion. The protective surface layer of cells has been worn away in places. This suggests recent or ongoing surface injury.
Ulceration. A deeper loss of the lining than erosion. It is common in inflammatory bowel disease and is a frequent reason for bleeding.

Not every report lists all of these, and which ones appear depends on how large the polyp was and how recently the tissue was injured.

Dysplasia

Dysplasia means the cells look abnormal under the microscope in a way that could lead to cancer. It is rarely found in an inflammatory polyp. When it is found, it almost always occurs in someone with long-standing inflammatory bowel disease.

Years of repeated inflammation can eventually cause cells in the colon lining to develop abnormal features. If dysplasia is present, your report will say so clearly. It may be described as low grade or high grade.

Dysplasia found in a person with inflammatory bowel disease is handled differently from dysplasia in an ordinary polyp. It usually leads to a detailed discussion with a gastroenterologist and a closer look at the rest of the colon. Your doctor will explain what it means in your case.

Margins

The margin is the cut edge of the tissue that was removed. Most reports for an inflammatory polyp do not mention it at all. Margins are assessed when tissue left behind could become cancer, and that does not apply here.

If your report does comment on the margin, a positive or unassessable result carries little weight. Benign healing tissue left at the site is not on a path toward cancer, and it rarely leads to another procedure.

What an inflammatory polyp means if you have inflammatory bowel disease

Most inflammatory polyps are found in people with ulcerative colitis or Crohn’s disease. In that setting the polyp is a marker of how much inflammation the colon has been through.

Whether inflammatory polyps themselves raise the risk of colorectal cancer has been debated for years. Older guidelines treated them as a risk factor and shortened the surveillance interval because of them. Several large studies since then found no independent increase in risk, once the extent and severity of the colitis were accounted for, while other reviews still report an association. The question is not settled.

What is agreed is that the polyps signal significant past inflammation, and that the inflammation itself is the established risk. Your surveillance schedule is therefore built on the factors that track that risk directly:

How long you have had the disease.
How much of the colon is involved.
Whether you also have primary sclerosing cholangitis, a liver condition that raises the risk substantially.
Whether colorectal cancer runs in your family.
Whether dysplasia has ever been found in your colon.

One practical problem is easier to state. When many inflammatory polyps are present, they make the surrounding lining harder to examine, and flat areas of dysplasia can hide among them. Your gastroenterologist may therefore sample representative polyps rather than remove every one, and may take a different approach to examining the colon.

What happens after this diagnosis?

In most cases, no further treatment is needed once an inflammatory polyp has been removed. Removing it is both the diagnosis and the treatment for that particular growth. What comes next depends on the cause of the inflammation.

No underlying condition identified. If you have no history of inflammatory bowel disease or another ongoing inflammatory condition, you usually don’t need polyp-specific follow-up. Routine colorectal cancer screening continues as normal.
Inflammatory bowel disease. Surveillance colonoscopy continues on the schedule set for your disease, whether or not inflammatory polyps were found. Your gastroenterologist sets the interval based on your disease history and the factors listed above.
An infection or another temporary cause. Treating the cause usually resolves the polyps, and you don’t need separate follow-up for them.
A large polyp or a difficult removal. Your doctor may look again at the site to confirm it has healed.
Dysplasia found in the polyp. This changes the plan. It leads to a discussion about surveillance frequency and often to specialist review.

Your pathology report is one of several things your doctor weighs when setting the plan. What happens after your pathology report describes the wider process.

Questions to ask your doctor

What caused the inflammation that led to this polyp?
Where in the colon or rectum was it found?
How many polyps were found, and were any other types of polyp present?
Was dysplasia found in the polyp?
Do I have an underlying condition that needs treatment?
Does this finding change my colonoscopy schedule at all?
If I have inflammatory bowel disease, how well controlled is the inflammation now?
Do the polyps make it harder to examine the rest of my colon?
When should my next colonoscopy be?
Should I be referred to a gastroenterologist if I am not already seeing one?
Are any changes to my treatment or medications needed?
Does this finding change my overall risk of colorectal cancer?