Anal polyp removal

Anal polyps are small growths on the inner lining of the rectum. They can be classified as benign or malignant (cancerous). The risk of cancer is strongly associated with the type and size of the polyp you have.

Cancer risk by polyp type

• Tubular adenoma – 5% risk of cancer
• Tubulo-villous adenoma – 20% risk of cancer
• Villous adenoma – 40% risk of cancer

Cancer risk by polyp size

• <1cm – <1% risk of cancer
• 1-2cm – 10% risk of cancer
• >2cm – 15% risk of cancer

Polyps of the colon and rectum are very common, they affect about 1 in 4 people at some point in their lives. They are more common in those aged 60 and above, this is why screening is so important in that age group.

Most polyps do not cause any symptoms, they are often picked up during screening for bowel cancer. Larger polyps may sometimes cause rectal bleeding, usually invisible to the naked eye.

Occasionally, a polyp may protrude from the anus. Large villous adenomas (a type of polyp) may rarely cause watery diarrhea leading to low blood levels of potassium (a condition called hypokalemia) on the long run.

Most polyps won’t turn into cancer. But there is a type called adenoma, which may eventually become cancerous unless removed. It is believed that most bowel cancers develop from adenoma polyps. Regular screening is the best way to prevent polyps from developing into colon cancer. Colonoscopy is a great method for both identifying and removing colorectal polyps.

During colonoscopy a flexible illuminated camera tube called a colonoscope is inserted into your anus and carefully pushed up into your bowel while you are sedated and sleeping. The instrument has a wire attached to it which allows your doctor to either burn off (cauterise) or cut off (snare) the polyp. Both of these methods are painless.

In rare cases, part of the bowel may need to be removed surgically. This is usually only done when the polyp shows some cell changes, if it is particularly large, or if there are multiple polyps.

After the polyp has been removed, it is sent to a lab for tests to see if:

• there is a sign of malignancy
• the polyp has been completely removed
• there is a risk of it regrowing

If there is a cancerous change in the polyp, you may need further treatment depending on the degree and extent of the change. Most benign colon and rectal polyps are quite small and can be removed with the help of the colonoscope. Very small polyps are destroyed with a forceps that grasps and removes small pieces of the rectal lining. Larger polyps are usually removed with a noose-like metal snare. Before the intervention, standard pre-operative blood and urine studies are done. Patients are also given medicated enemas to clean the bowel.

Overall, colonoscopy is a very safe test, and when it is necessary concerns over complications aren’t a valid reason for putting it off or avoiding it altogether. The lifetime risk of having colorectal cancer is in fact more than 12 times higher than that of complications during colonoscopy. However, as with any medical procedure, complications are possible.

If a colectomy is recommended for a benign, or non-cancerous, growth, it is usually because that growth is symptomatic in some way (bleeding or causing a blockage) or to prevent it from becoming cancerous.
Complications are very rare, however there is a slight risk of perforation of the colon (less than 1 in 1,000), but only if a polyp is removed during the test. There is a minor risk of bleeding due to damage to the inner lining of the colon (less than 3 in 1,000), but again, only if a polyp is removed.

There are certain risks associated with anesthesia too. These will be explained to you in detail before the procedure.

Whether or not a patient is eligible for laparoscopic polypectomy depends mainly on the medical condition(s) they have. Several other factors are taken into account including the patient’s body type and overall health, the presence of scars left over from previous operations on the abdomen, a history of bleeding disorders and pregnancy.

Be aware of the doctor’s recommendations regarding any restrictions, such as not eating solid food on the day before your appointment. Make a list of all your medications, including vitamins and supplements.
Your doctor will want to know about any known medical conditions you have as well as information about recent lifestyle changes or stressors in your life.

After your colonoscopy you will need to spend some more time in the recovery room until the effects of the pain medication wear off. You will not be alert enough to go home right after the intervention so it is recommended that you stay one night in our hospital. You will be asked to refrain from drinking alcohol, making important decisions and operating heavy machinary for the remainder of the day. All you need to do is take a rest and eat light meals at first. You may feel bloated or pass gas for a few hours after the exam, as you clear the air from your colon. Walking may help relieve these uncomfortable symptoms.

If a polyp has been removed during your colonoscopy, you may be required to follow a special diet for a while.

After the test you may also notice a small amount of blood with your first bowel movement. Usually this isn’t a cause for alarm. Consult your doctor if you continue to pass blood or blood clots, and in case of persistent abdominal pain or fever. While unlikely, this may occur 2 to 7 days after your colonoscopy.

Follow-up depends on what type of polyp was removed during colonoscopy. Small hyperplastic polyps located in the lower part of the colon typically do not require follow-up, and a repeat colonoscopy is only recommended after 10 years as long as you do not have any additional risk factors (personal or family history of polyps or colon cancer, etc.).

You may be invited to have another colonoscopy sooner than 10 years if a more dangerous type of polyp is found, if you have multiple polyps or if your polyp could not be removed for some reason.

In case cancer is found, your doctor will recommend further testing and a personalised course of treatment which may involve surgery, radiotherapy, chemotherapy or a combination of these.