Colon polyps: what they are, why they can be dangerous and how they are removed

The large intestine (colon) is the last part of the digestive system and is about 1.5 meters long. Its final section, about 15 centimeters long, is the rectum, which ends in the anal canal. The inside of the bowel is covered by a mucous lining whose cells are constantly renewed.

Sometimes this renewal gets out of order: cells multiply excessively in one spot and form a bulging growth that sticks out into the bowel. This is called a polyp. In everyday speech, people sometimes call it “a fleshy growth in the bowel”.

By shape, polyps come in two kinds:

• pedunculated polyps look like a mushroom: a round head on a thin “stalk”;
• flat (sessile) polyps attach to the bowel wall with a broad base, stick out only slightly and are harder to see.

Polyps range in size from a few millimeters to several centimeters. They can develop in both the colon and the rectum. A rectal polyp that sits close to the anus can even be felt during a finger examination. Polyps are very common, especially after the age of 50. They are often found by chance during an examination done for another reason.

The most dangerous thing about a polyp is that it is silent: in most cases, it causes no symptoms at all. Symptoms usually appear once a polyp has grown larger:

• blood in the stool or on toilet paper — bright red, sometimes dark;
• mucus in the stool;
• constipation, diarrhea or alternating between the two for weeks;
• abdominal cramps and bloating (when a large polyp narrows the inside of the bowel);
• iron deficiency anemia caused by hidden bleeding: tiredness, pale skin, shortness of breath;
• with a polyp in the lower rectum — a growth that comes out during a bowel movement and goes back in, a feeling of a foreign body inside or a feeling that the bowel has not emptied completely.

The same symptoms also occur with hemorrhoids (piles), an anal fissure, inflammatory bowel disease and colorectal cancer. There is no way to tell them apart at home. We explain the possible causes of bleeding in detail in our article on blood on toilet paper. Remember: no bleeding does not mean no polyp.

A note for women: iron deficiency is often put down to menstrual periods. After menopause, and whenever anemia has no clear cause, it is important to have your bowel checked.

A polyp forms as a result of changes that build up in the cells over the years. The following factors increase the risk:

• age — polyps are found more often after the age of 45–50;
• family history — colorectal cancer or a large polyp in a parent, sibling or child;
• having had polyps removed before — the likelihood of new polyps is higher;
• long-standing inflammatory bowel disease — Crohn's disease and ulcerative colitis;
• inherited syndromes (familial adenomatous polyposis, Lynch syndrome) — these are rare, but in such cases polyps and cancer can develop at a young age;
• lifestyle — eating a lot of red and processed meat and little fiber, meat charred over an open flame, lack of physical activity, excess weight, smoking and alcohol;
• sex — adenomatous polyps are somewhat more common in men.

The type of a polyp cannot be determined by eye; it can only be identified accurately under a microscope, through histological examination. The main types are:

• Adenomatous polyp (adenoma). The most common and most important type. An adenoma is considered a precancerous growth: most colorectal cancers develop from exactly this kind of polyp. But only a small proportion of adenomas turn into cancer. The risk increases with the size of the polyp (especially if it is larger than 1 cm), its structure and the degree of change in its cells (dysplasia).
• Hyperplastic polyp. Usually small and often found in the rectum and sigmoid colon. The risk of it turning into cancer is very low.
• Serrated (saw-toothed) polyps. Under the microscope they look similar to hyperplastic polyps, but some types can turn into cancer. They are often flat, which makes them hard to see.
• Inflammatory polyps. These form after long-standing colitis and usually do not turn into cancer themselves.

Why can a polyp turn into cancer years later?

Changes in the cells of an adenoma build up step by step: a small polyp grows, the dysplasia becomes more advanced, and eventually cancer may develop. This process usually takes many years, often close to 10. It is precisely this “window of time” that makes it possible to find and remove a polyp before it turns into cancer.

“Polyps” in the anal area are something else

Most growths in the anal canal that people call “polyps” are actually a hypertrophic anal papilla (a small enlarged projection in the anal canal) or a fibrous polyp. They often develop alongside a chronic anal fissure or hemorrhoids, are benign and are not considered precancerous in themselves. If such a growth causes symptoms, it is removed with a minor procedure — for example, with electric current (electrocoagulation) — and in this case, too, it is sent for histological examination.

Do not confuse them with gallbladder polyps

A gallbladder polyp found on ultrasound develops in a completely different organ and is monitored according to different rules. We cover it on our gallbladder page.

Do not wait — seek urgent care in the following cases:

• heavy bleeding, bleeding that will not stop or bleeding with clots;
• black, tarry stools;
• dizziness, severe weakness or fainting along with bleeding;
• severe abdominal pain, vomiting, or being unable to pass gas or stool.

Your visit starts with a conversation: we ask about your symptoms, the medications you take and any illnesses in your family. Then a proctological examination is done. You lie on your side with your knees drawn up toward your stomach. The examination takes a few minutes and is done in private.

• A digital rectal exam allows the doctor to feel growths close to the anus.
• Anoscopy is a look at the anal canal and lower rectum through a short, thin instrument. It is usually done during the visit, without any special preparation.
• Rectoscopy (rigid sigmoidoscopy) shows the rectum and the beginning of the sigmoid colon.
• Colonoscopy is the main test for finding polyps: it lets the doctor see the entire colon and remove any polyp found right on the spot. We describe the preparation, sedation (a light, medication-induced sleep) and what happens during the procedure in detail on our colonoscopy page.

A fecal occult blood test is useful for screening (preventive checks for people without symptoms), but it can only detect growths that bleed and misses most small polyps. If the test is positive, you need a colonoscopy. We also recommend a colonoscopy for patients aged 40 and over who suffer from constipation and are found to have hemorrhoids on examination.

Conservative approach: what it can and cannot do

A polyp cannot be “dissolved” with medication, diet, suppositories or folk remedies. The treatment for a colon polyp that has been found is to remove it. Diet and lifestyle serve a different purpose: they lower the risk of new polyps forming. A small anal papilla that causes no symptoms, on the other hand, is sometimes simply monitored while the underlying condition — an anal fissure, for example — is treated.

Surgical and minimally invasive methods

Colonoscopic polypectomy. Most polyps are removed during colonoscopy, without any incisions. A thin wire loop (snare) is passed through the channel of the colonoscope. The loop is placed around the stalk of the polyp, as close to the bowel wall as possible, and tightened to cut the polyp off. When needed, an electric current passed through the loop seals small blood vessels and prevents bleeding. Very small polyps are removed with special forceps or with a “cold” snare, without current. The inner lining of the bowel does not respond to cutting with pain, so polyp removal usually cannot be felt.

Large and flat polyps. These polyps are removed whole or piece by piece after fluid is injected under the lining (endoscopic mucosal resection). Sometimes a separate session is scheduled for this.

Histology is a must. Every removed polyp is sent to the laboratory. The results are usually ready within a few days to two weeks. If cancer cells are found in the polyp, more extensive treatment may be needed, such as surgically removing that section of the bowel. In such cases, the plan is usually decided jointly by a surgeon and an oncologist.

Combined (“bouquet”) surgery. If, along with a polyp, you have another problem such as hemorrhoids, an anal fissure or a rectocele, all of them can be treated in the same session when there is a medical indication — with one anesthetic and one recovery period. We explain this approach on our surgical and conservative treatment page.

These timeframes are averages; we will give you exact timelines after the examination. If you have heavy bleeding, severe or worsening abdominal pain, or a fever — this can happen up to two weeks after polyp removal — do not wait, seek urgent care.

1. Start screening on time. For people at average risk, colorectal cancer screening is recommended from the age of 45–50. If colorectal cancer or a large polyp has occurred in your family, you need to start earlier.
2. Fill half your plate with plant foods. Eat vegetables, fruit, legumes and whole grains — about 400–500 grams of fruit and vegetables a day.
3. Cut down on red and processed meat. Eat sausages, hot dogs and smoked meat only rarely, and cook meat without charring it over an open flame.
4. Stay active and keep your weight in check. At least 30 minutes of brisk walking a day is also good for your bowel function.
5. Quit smoking and limit alcohol. Both increase the risk of polyps and cancer.

Our patient, who came to us from outside Baku, was troubled by painful symptoms. A polyp found during colonoscopy was removed. In the same session, her rectocele (a bulging of the front wall of the rectum into the vagina) was also repaired: the back wall of the vagina and the pelvic floor muscles were restored (posterior colporrhaphy and levatorplasty). Our patient said she felt no pain during the procedure and was feeling well. Every patient's situation is different.