Colon and rectal polyps are small clumps of growth on the linings of your colon on rectum. They may grow anywhere between a few millimetres, up to 1 centimetre or larger. Colon and rectal polyps usually occur sporadically, and are typically harmless. However, larger growths may cause obstructions, and in rare cases can develop into colon cancer [1].
What are colon and rectal polyps?
Colon and rectal polyps are lumpy protrusions in the colon lumen. These growths typically occur sporadically and can grow from the mucosa. Colon polyps are typically classified as [1]:
Adenomatous polyps – Adenomatous polyps can be tubular (>80%), villous (5 - 15%), or tubulovillous (5 - 15%). Adenomatous polyps can become dysplastic as they slowly grow. Dysplasia in polyps is an indicator that the growth can become malignant over time.
Serrated polyps – Serrated polyps can further be classified as sessile, and traditional. Sessile serrated polyps can become malignant if dysplasia is present. While traditional serrated polyps are rare and have significant potential to become malignant.
Non-neoplastic polyps – Non-neoplastic polyps can either be hyperplastic or juvenile. Hyperplastic polyps are common and have low malignant potential, while juvenile polyps are benign hamartomas and typically develop in childhood.
What are the symptoms of colon and rectal polyps?
Colon and rectal polyps are typically asymptomatic. You may not even know you have colon polyps until your healthcare provider finds it during screenings, or when you start having symptoms. Larger polyps may cause symptoms, some of which include:
Pain
Slime or mucus in faeces
Blood in faeces, which may appear as read streaks on stool or make your stool appear black
Changes in bowel movement, such as constipation or diarrhoea
Anaemia, due to bleeding from polyps
These symptoms may also be caused by other factors such as haemorrhoids, use of medications, or dietary changes that affect your bowel movement. Diagnosis of colon polyps can often be missed. Hence, individuals with multiple risk factors for polyps are recommended to go for regular or routine screening.
Colon and rectal polyps are typically benign growths along the lining of the colon or rectum.
What causes colon and rectal polyps?
Studies report that genetic mutations contribute to the development of colon and rectal polyps. For example, in inherited diseases such as familial adenomatous polyposis (FAP), a mutation of the adenomatous polyposis coli (APC) tumour suppressor gene contributes to multiple colonic adenoma formation [2].
This inactivating mutation of APC tumour suppressor gene was also observed in sporadic cases of colon and rectal polyps, with other genetic mutations reported such as KRAS and TP53 genetic mutations in larger polyps (> 1cm) [2]. Although not all colon and rectal polyps become cancer, colorectal polyps formation and development is of clinical concern due to the fact that most cases of colorectal cancers arise from these polyps [1 - 3].
Why do colon and rectal polyps need to be removed?
Think of the polyps as weeds in a garden — they have the potential to grow, change, and in some cases, become cancerous. Essentially, removing these polyps before they grow can help prevent your risk of colorectal cancer. Polyps with a higher risk of becoming cancerous include:
Sessile polyps (flat, broad-based)
Villous adenomas
Additionally, polyps can also grow and cause blockages in the colon. Others can lead to bleeding, anaemia, or changes in bowel habits, though these tend to be uncommon
What are the risk factors of colon and rectal polyps?
Most colon polyps are sporadic and appear with no clear cause. However, certain groups of people are at higher risk of developing colon and rectal polyps.
Age – Polyps are more commonly observed in individuals aged over 50 years.
Diet – High-fat and low-fiber diets are associated with the development of colon and rectal polyps.
Obesity – Excess body weight, and diabetes has been associated with colon and rectal polyps, as well as lack of physical activity.
Tobacco and alcohol use – Heavy tobacco use and alcohol intake have also been linked to incidences of colon polyps.
Family history/genetics – Certain inherited conditions can also increase the risk of colon and rectal polyps, such as Lynch syndrome, familial adenomatous polyposis (FAP), Gardner syndrome, juvenile polyposis syndrome, and MUTYH-associated polyposis (MAP).
Certain risk factors such as age and genetics are non-modifiable, however, risk of colon and rectal polyps can be reduced by making changes to your diet and lifestyle. Additionally, regular screenings for individuals aged 50 and above are highly recommended to detect and screen for polyps.
How are colon and rectal polyps diagnosed?
Colon and rectal polyps may not always present symptoms, hence you may not know that you have colon or rectal polyps until later. Colorectal polyps are typically detected through screenings such as a colonoscopy. Your doctor may also perform other tests to diagnose colon and rectal polyps.
Colonoscopy – A colonoscopy involves inserting a small tube with a light and camera at the end to view the inside of the colon. This is typically how your doctor detects and diagnoses polyps. Your doctor may also take several samples of the polyps for further laboratory tests and to determine the malignant potential of the growths.
Blood tests – Your doctor may perform a blood test to look for signs of anaemia from chronic bleeding caused by polyps. You may also be asked to do a genetic testing to screen for genetic variations that may contribute to polyps.
Stool tests – Stool samples can be valuable in the diagnosis of colon and rectal polyps. Faecal occult blood tests are typically done to look for traces of blood in the stool, which can be caused by polyp bleeding. Further lab tests can also be done to test the DNA found in your stool for cancer markers or genetic mutations.
As mentioned, regular health screening to detect polyps early can be helpful in monitoring polyps growth and to remove them if they are at risk of becoming malignant. In general, it is highly recommended for individuals aged 50 years and above to perform regular check-ups and screenings.
What’s the best age to undergo a colonoscopy?
With the rising number of young adults developing colon cancer, the ideal age to start screening for average-risk individuals would be 45 years old. High-risk individuals with a family history of cancer are recommended to screen earlier.
Risk Category
Recommended age
Recommended frequency
Average-risk
45 years old
Every 5 years
High-risk
40 years old
Every 3-5 years
Individuals with symptoms
Immediately, regardless of age
As needed
Individuals with Inflammatory Bowel Disease (IBD)
Start from diagnosis
Every 1-3 years
Early detection saves lives, greatly reducing your chances of colorectal cancer by removing precancerous polyps early.
How are colon and rectal polyps treated?
Colon and rectal polyps treatment is usually via removal of the growth upon detection. Several methods of polyp removal include [1, 3]:
Polypectomy – Polypectomy refers to the removal of polyps. The procedure can be done in a number of ways, such as:
Endoscopic forceps polypectomy – Forceps polypectomy involves using forceps to remove or biopsy the polyp. The technique can also be ‘hot’ or ‘cold’, whereby hot forceps polypectomy refers to the use of electrocautery to limit bleeding risk [4].
Endoscopic snare polypectomy – Snare polypectomy involves using a wire loop to snare the polyp and remove it. Similar to the use of forceps, snare polypectomy can be ‘hot’ ot ‘cold’ [4].
Endoscopic submucosal dissection – Submucosal dissection is usually performed on sessile polyps or large polyps which cannot be removed by forceps or snare polypectomy. The procedure is technically demanding and complicated, but can be an option for patients who wish to avoid more invasive surgical procedures.
Colectomy – Colectomy refers to the removal of the colon, and can be either partial or total colectomy. Typically, colectomy is done for patients with FAP or MAP as a prophylactic measure [1]. After the removal of the colon, the doctor may join the ileum to the rectum in a procedure called ileorectal anastomosis.
Proctocolectomy – Proctocolectomy refers to the removal of the colon and rectum. The procedure is also followed with ileal pouch anal anastomosis, which involves making a new pouch from part of the small intestine to replace the rectum. The pouch is then attached to the anal sphincters. This allows the patient to pass their bowels normally. Proctocolectomy is also indicated for patients at high risk of developing colorectal cancer, such as patients with FAP [5].
Summary
Colorectal polyps may not be an obvious cause of concern. But risks of the polyps developing into malignant growths should not be ignored. Ideally, early detection and removal can prevent or minimise risks of malignancy or cancer. Hence, high risk individuals, such as the elderly, are encouraged to perform regular or routine health screens.
For more information about colon and rectal polyps, and the risks of colorectal cancer, reach out to us to book a consultation session with our doctors.
Frequently Asked Questions
Can colon and rectal polyps go away on their own?
Colon and rectal polyps do not go away on their own. Polyps can be removed relatively easily if they are detected early.
When should I visit the doctor for polyps?
You may want to visit a doctor if you experience symptoms that might indicate polyps, such as blood in your stool. However, not all polyps are symptomatic, which makes detection difficult. Regular screening is recommended if you are over 45 years old or have other risk factors.
When should you worry about colon polyps?
In some cases, it is hard to tell whether you have colon polyps, this is why routine screening is recommended. If you experience signs and symptoms associated with colon and rectal polyps, a visit to your healthcare provider is highly recommended. Remember that every colonic polyp represents a cancer risk
Can a doctor tell if a polyp is cancerous during colonoscopy?
A colonoscopy on its own is not enough to confirm a cancer diagnosis. The colonoscopy allows your doctor to obtain tissue samples required for biopsy tests to confirm whether the polyp is cancerous.
Is removing polyps a major surgery?
Polyp removal is a minimally invasive surgery and is often done during a colonoscopy, hence no surgical incision is made and no pain will be experienced during and also after the procedure. However, other types of surgery such as colectomy and proctocolectomy are major surgeries, these surgeries are done in more severe cases or when a cancer diagnosis is made.
Can colon polyps grow back after removal?
Yes, new colon and rectal polyps may develop, either as recurrences or as new growths. It is recommended to attend follow-up screenings at least annually with your doctor [6].
References
Meseeha M, Attia M. Colon Polyps. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430761/
Sullivan BA, Noujaim M, Roper J. Cause, Epidemiology, and Histology of Polyps and Pathways to Colorectal Cancer. Gastrointest Endosc Clin N Am. 2022 Apr;32(2):177-194. doi: 10.1016/j.giec.2021.12.001. Epub 2022 Feb 22. PMID: 35361330; PMCID: PMC9924026.
Shussman N, Wexner SD. Colorectal polyps and polyposis syndromes. Gastroenterol Rep (Oxf). 2014 Feb;2(1):1-15. doi: 10.1093/gastro/got041. Epub 2014 Jan 23. PMID: 24760231; PMCID: PMC3920990.
Chandrasekhara V, Kumta NA, Abu Dayyeh BK, Bhutani MS, Jirapinyo P, Krishnan K, Maple JT, Melson J, Pannala R, Parsi MA, Sethi A, Trikudanathan G, Trindade AJ, Lichtenstein DR. Endoscopic polypectomy devices. VideoGIE. 2021 Apr 2;6(7):283-293. doi: 10.1016/j.vgie.2021.02.006. PMID: 34278088; PMCID: PMC8267590.
Ng KS, Gonsalves SJ, Sagar PM. Ileal-anal pouches: A review of its history, indications, and complications. World J Gastroenterol. 2019 Aug 21;25(31):4320-4342. doi: 10.3748/wjg.v25.i31.4320. PMID: 31496616; PMCID: PMC6710180.
Wang QP, He XX, Xu T, Ji W, Qian JM, Li JN. Polyp recurrence after colonoscopic polypectomy. Chin Med J (Engl). 2020 Sep 5;133(17):2114-2115. doi: 10.1097/CM9.0000000000000990. PMID: 32804729; PMCID: PMC7478769.
