Anal Cancer Screening

Anal cancer screening is the process of using a series of tests and procedures with the goal of detecting and preventing abnormal cells that are not yet cancerous (called dysplasia) from becoming cancerous tumors and potentially spreading to other parts of the body. Simple anal pap tests, similar to cervical pap tests given to screen for cervical cancer in women, are given to detect the presence of abnormal cells. More detailed examination is done with a procedure called high resolution anoscopy (HRA) with suspicious tissue requiring a biopsy to confirm or deny the presence of cancer. A procedure called infrared coagulation (IRC) is often used to destroy detected abnormal cells. After any initial screening and treatment usually two or three additional screenings and treatments are required to insure that all abnormal cells have been detected and destroyed.

Listed below are frequently asked questions that will provide more in depth information regarding the various tests and procedures associated with anal cancer screening. Click on a question to see the answer.

What is an anal Pap test?

An anal Pap test is a screening tool that looks for abnormal cells that could be a precursor for anal cancer. The test is performed by inserting a swab into the anus to collect a sample of cells. These cells are then examined in a lab under a microscope. If the cells look abnormal then the next step is a closer inspection of the anal canal using a special tool called a colposcope during a procedure called High Resolution Anoscopy (HRA) or anal colposcopy.

What is High Resolution Anoscopy (HRA)?

HRA is a procedure for examining and evaluating the anal canal usually given after an anal pap test shows abnormal cells. During the procedure a vinegar like solution is applied in the anal canal in order to make abnormal tissues more visible; an iodine solution may also be used to help better define abnormal tissues. A small round tube called an anoscope and a magnifying instrument called a colposcope are used to thoroughly examine the anal canal. If indications warrant it, a small piece of abnormal tissue may be taken for biopsy purposes. A digital rectal examination is also done at the time of the procedure.

HRA is performed in an office setting in either a bent over or lying position and usually takes approximately 15 minutes. There is no preparation required and in fact enemas and suppositories are not recommended prior to the procedure. HRA is usually well tolerated with individuals and any discomfort that may be experienced is usually mild with cases of bleeding or infection being extremely rare.

Why is a biopsy necessary?

Anal pap tests or HRA procedures merely indicate the presence of potentially cancerous cells but a biopsy is the only way to make an actual diagnosis of cancer. The biopsy is done as part of the HRA procedure. Pain after a biopsy is usually minimal and over-the-counter pain relievers should help to provide comfort. A small amount of bleeding may occur for a day or two after the biopsy and may last up to a week; anal insertions of any kind should be avoided until all bleeding stops.

Biopsy results that do not indicate an actual presence of cancer can still describe low grade or high grade pre-cancerous lesions. This information is critical in determining the best type of treatment. Low grade lesions do not necessarily require treatment, but they should be monitored with periodic HRA. High grade lesions however require treatment to prevent progression of the abnormal cells to cancer.

What is Infrared Coagulation (IRC)?

IRC is the application of heat for a short burst (about 1.5 seconds) to destroy (ablate) abnormal anal cells while sealing the tiny blood vessels resulting in minimal bleeding. The procedure is performed in an office setting with no suppositories or enemas required with local anesthetic being used as necessary.

What are the after care instructions following an HRA or IRC procedure?

After having an HRA or IRC procedure you need a follow-up appointment within two weeks; we call our patients to schedule that appointment but if not contacted within two weeks please contact us to have an appointment scheduled. The following are instructions you should follow after having your procedure:

General Instructions: You should expect to have bleeding with bowel movements for up to two weeks. Keeping your stool soft during these two weeks will decrease your bleeding and discomfort. Do not use any enemas, suppositories or engage in anal receptive sex until all bleeding and discomfort have resolved. Call the clinic if you have increased pain, bleeding, fever, chills or night sweats.

Diet Instructions: Resume your normal diet. Use of an over-the-counter fiber supplement is recommended for the next two weeks to keep your stool soft. Maintain adequate fluid intake.

Medication Instructions: You should continue all of your usual medications. If you have received a prescription for a pain medication, it may make you sleepy so do not drive, drink alcohol, or operate machinery while taking it.

Aldara (Imiuimod) Cream Instructions: If you have been given a prescription for Aldara cream, please follow these instructions. Aldara cream is most effective if used three times a week for four months.

  • Use Aldara cream three nonconsecutive days per week before you go to sleep. (For example, apply Aldara as directed on Mondays, Wednesdays and Fridays OR on Tuesdays, Thursdays and Saturdays.) DO NOT use Aldara cream two days in a row.
  • Wash off the applied Aldara cream in the morning.
  • Expect some irritation from the use of Aldara cream. You may use Calmoseptine ointment after washing Aldara off the skin to relieve any irritation.

Once treated will I need to return for additional screening and/or treatments?

Yes. After initial treatment, you will need to have periodic anal Pap tests and/or HRA to see if there are any additional areas that require treatment. Sometimes two or three treatments are required before all the abnormal cells are found and destroyed. However, a few trips to the doctor's office are far better than needing surgery and hospitalization for cancer.