Bowel polyps are small growths that develop on the inner lining of the colon (large bowel) or rectum. They are relatively common, affecting approximately 15% to 20% of the UK population, particularly people over the age of 60. These growths usually do not cause symptoms but can sometimes lead to complications. Polyps are generally less than 1cm in size but can grow larger, sometimes several centimetres.

Forms of Polyps:

• Sessile Polyps: Appear as small raised areas or bulges directly attached to the lining of the colon without a stalk.
• Pedunculated Polyps: Resemble a grape on a stalk, where the growth is connected to the colon lining by a thin stem.
• Clustered Polyps: Comprise many small bumps appearing together.

While polyps are not usually cancerous, some can become cancerous over time if not removed. This is why polyps discovered during screening are typically removed to prevent potential cancer development. Some people develop just one polyp, while others may have several.

Causes of Bowel Polyps

The exact cause of bowel polyps isn’t entirely clear, but they result from abnormal cell production in the bowel lining, which causes cells to grow more rapidly than normal. Factors that may contribute include:

• Genetic Factors: Family history of bowel polyps or bowel cancer can increase the likelihood of developing polyps.
• Abnormal Gene Activity: Faulty genes can disrupt the normal cell renewal process in the bowel lining.

Symptoms of Bowel Polyps

Most people with bowel polyps remain unaware of their presence as they often produce no noticeable symptoms. However, larger polyps may lead to:

• Rectal Bleeding: Blood may be visible in stools.
• Mucus Production: Increased mucus may be noticeable during bowel movements.
• Bowel Habit Changes: This may include diarrhea or constipation.
• Abdominal Pain: Some individuals may experience pain in the abdomen.

Detection and Diagnosis

Bowel polyps are commonly identified during routine bowel investigations for other reasons, such as:

• Sigmoidoscopy: An examination of the rectum and the last part of the large bowel using a flexible tube with a camera.
• Bowel Cancer Screening Programs

If polyps are found, further investigations like a colonoscopy or CT colonography are performed to examine the entire large bowel and remove any additional polyps.

Treatment for Bowel Polyps

Several methods are available for removing polyps. The most common involves:

• Snaring During Colonoscopy: A wire loop (snare) is used to remove the polyp, often employing an electric current to cut it off or cauterize it. This procedure is typically painless.
• Surgical Removal: In rare cases, if a polyp is particularly large or shows cell changes, part of the bowel may need to be surgically removed.

After Treatment: The removed polyps are sent for laboratory analysis to determine:

• Whether the polyp has been completely removed.
• The likelihood of recurrence.
• Any signs of cancerous changes.

If any cancerous cells are present, additional treatments may be recommended.

Outlook and Follow-Up

Some individuals will require regular follow-up colonoscopies because polyps can recur. In rare cases where polyps run in families, regular check-ups are essential to monitor and remove any new growths, reducing the risk of developing bowel cancer. Typically, follow-up examinations are scheduled every 3 to 5 years.