Anal examination (anoscopy) and biopsy

A specialist doctor examines your anus with a short tube called an anoscope. Doctors call this an anal examination or an anoscopy. You might also hear it called a high resolution anoscopy.

Your doctor can take a sample of tissue (biopsy) from any abnormal areas during the procedure.

Why you might have anoscopy and biopsy

You might have an anoscopy and biopsy to:

• find out what is causing your symptoms
• help diagnose anal cancer
• find out more about the size and position of an anal cancer (the stage)

Preparing for an anoscopy and biopsy

You do not normally need to do anything to prepare yourself for an anoscopy and biopsy. But the hospital will tell you if there is anything to avoid beforehand. This may include not having anal sex or using enemas , anal creams or douches (used to keep the rectum clean) for 24 hours before the examination. 

What happens during an anoscopy and biopsy

It’s normal to feel anxious about this test but it usually only takes a few minutes.

Your doctor should ask if you would like to have someone else (a chaperone) in the room while you have the test. This is normal for intimate examinations or tests. The chaperone is another staff member from the clinic. It’s up to you whether you decide to have one or not. Ask for a chaperone if it hasn’t been offered and you would like one. You may also be able to have a friend or relative with you.

You usually change into a gown and lie on a bed. This may be on your side with your knees drawn up towards your chest. Tell your doctor if you are not able to do this as there are other positions you can lie in.

About 10 minutes before the examination, your doctor might put some local anaesthetic into your anus. This will numb the area.

When the area is numb, your doctor puts some lubricating jelly on the end of the anoscope then gently puts it into your anus. The middle of the anoscope (obturator) has a rounded end to make it easier to put in. Your doctor then gently pulls the obturator out of the anoscope so they can see down the middle and into your anus.

Your doctor takes biopsies from any abnormal areas. Sometimes they apply a liquid to the lining of the anus to help show up these areas. The biopsy is sent to a specialist doctor called a pathologist. They look at the biopsy under a microscope to check for cancer or abnormal cells. Abnormal cells in the lining of your anus is called anal intraepithelial neoplasia (AIN).

Your doctor might also examine your back passage (rectum) using a slightly longer tube. This is called a proctoscope.

These tests may be uncomfortable but are not normally painful. You usually have them as an outpatient, so you should be able to go home as soon as the test is over.

If you have a biopsy, you might notice a small amount of bleeding for a day or so afterwards.

Anoscopy in women

Your doctor might also do a separate examination to check your cervix and vagina . This is because they are close to the anus. Doctors call this a pelvic examination.

Examination under anaesthetic (EUA)

Sometimes your doctor may recommend an anoscopy and biopsy under an anaesthetic . This might be either:

• an injection into your back to numb the lower part of your body
• a general anaesthetic so you are asleep during the procedure

Your doctor can also take biopsies during the examination.

You should be able to go home when the test is over and you’ve recovered from the anaesthetic.

Possible risks

Anoscopy and biopsy is a safe test but there are some risks. These might include:

• discomfort after the examination

• a small tear in the skin around the anus (perianal skin) or the inner lining of the anal canal (mucosa)

• irritation or damage to a pile (haemorrhoid)

• infection - this is very rare. Speak to your doctor or nurse if you have any signs of infection such as a high temperature or shivering

Getting your results

You normally get your results 1 to 3 weeks after the test. Ask your doctor or nurse how long it will take to get them. Contact them if you haven’t heard anything after a couple of weeks.

Waiting for test results can make you anxious. You might have the contact details for a specialist nurse. You can contact them for information and support if you need to. And it may help to talk to a close friend or relative about how you feel.