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Anal Warts and Anal Dysplasia Expanded


What are anal warts?

Anal warts (also called "condyloma acuminata") are a condition that affects the area around and inside the anus. They may also affect the skin of the genital area. They first appear as tiny spots or growths, perhaps as small as the head of a pin, and may grow quite large and cover the entire anal area. They usually appear as a flesh or brownish color. Usually, they do not cause pain or discomfort and patients may be unaware that the warts are present. Some patients will experience symptoms such as itching, bleeding, mucus discharge and/or a feeling of a lump or mass in the anal area. 


What causes anal warts?

Warts are caused by the human papilloma virus (HPV), which is transmitted from person to person by direct contact. HPV is considered to be the most common sexually transmitted disease (STD). You may be upset when you are given this diagnosis and it is important to note that anal intercourse is not necessary to develop anal condylomata. Any contact exposure to the anal area (hand contact, secretions from a sexual partner) can result in HPV infection. Exposure to the virus could have occurred many years ago or from prior sexual partners, but you may have just recently developed the actual warts.


How are anal warts diagnosed?

Although potentially sensitive and difficult to talk about, your doctor may inquire as to the presence or absence of risk factors to include a history of anal intercourse, a positive HIV test or a chronically weakened immune system (medications for organ transplant patients, inflammatory bowel disease, rheumatoid arthritis, etc).


Physical examination should focus primarily on the anorectal examination and evaluation of the perineum (pelvic region) that includes the penile or vaginal area to look for warts.  Digital rectal examination should be performed to rule out any mass.  Anoscopy is typically performed to look within the anal canal for additional warts.  This involves inserting a small instrument about the size of a finger into your anus to help visualize the area.  Speculum examination may also be performed to aid in vaginal examination in women.


Can I prevent myself from getting warts?

The safest way to protect yourself from getting exposed to HPV or any other STD, is to use safe sex techniques.  Abstain from sexual contact with individuals who have anal (or genital) warts. Since many individuals may be unaware that they suffer from this condition, sexual abstinence, condom protection or limiting sexual contact to a single partner will reduce the contagious virus that causes warts. However, using condoms whenever having any kind of intercourse may reduce, but not completely eliminate, the risk of HPV infection, as HPV is spread by skin-to-skin contact and can live in areas not covered by a condom.

The U.S. Food and Drug Administration (FDA) has approved the vaccine Gardasil (vaccine against certain types of HPV that more commonly cause cervical and other HPV-related cancers) in certain patients age 9 to 26 prior to HPV exposure (sexual activity) to prevent the development of HPV- related cancers and associated precancerous lesions (called dysplasia).  Your physician may recommend you to be evaluated if you would potentially be a candidate for this vaccine.  However, the vaccine’s role to prevent anal warts and anal cancer is unknown.


Do these warts always need to be removed?

Yes. If they are not removed, the warts usually grow larger and multiply. Left untreated, warts may lead to an increased risk of anal cancer in the affected area. Fortunately, the risk of anal cancer is still very rare.


What treatments are available for anal warts?

Topical options for treating warts


1. Medications: If warts are very small and are located only on the skin around the anus, they may be treated with a topical medication in the office and sometimes at home. Common topical medications applied directly to the warts are podophyllin, trichloroacetic acid and bichloroacetic acid. These office treatments do not require anesthesia and only take a few minutes to apply to the warts. Minor burning or discomfort may be experienced after treatment and, thus, most patients can return to work after the procedure. Your physician will recommend when to wash off the medication after treatment.


Topical agents that can be applied at home on small warts include Imiquimod or 5-fluorouracial (5-FU), although how well they work to eliminate anal warts completely is unknown. Side effects include skin irritation, burning and painful ulcerations of the skin. If you develop severe side effects, immediately stop using the cream and contact your physician.


 2. Cryotherapy: Anal warts may also be treated in the physician’s office by freezing the warts with liquid nitrogen.  Similar recovery as the topical agents mentioned above is expected.


Surgical options for treating warts:

Surgery provides immediate results, but must be performed using either a local anesthetic - such as Novocaine - or a general or spinal anesthetic, depending on the number and exact location of warts being treated. Fulguration (burning), surgical excision (removal), or a combination of both, are used to treat larger external and internal anal warts.


Must I be hospitalized for surgical treatment?

Surgical treatment of anal warts is usually performed as outpatient surgery.


How much time will I lose from work after surgical treatment?

Most people are moderately uncomfortable for a few days after treatment, and pain medication may be prescribed. Depending on the extent of the disease, some people return to work the next day, while others may remain out of work for several days to weeks. Pain, discomfort and slight bleeding are expected in the recovery period and may last at some level for several weeks. Excessive bleeding is abnormal and your physician should be informed immediately if you experience large amounts of bleeding.  Clear, yellowish or blood tinged drainage or moisture will be expected for days to weeks after the procedure. Placement of a pad and frequent dressing changes will help lessen the moisture and itching associated with the drainage.


Will a single treatment cure the problem?

When warts are extensive, your surgeon may wish to perform the surgery in stages.  Additionally, recurrent warts are common in over 50% of patients. The virus that causes the warts can live concealed in the skin that appears normal for several months before another wart develops. As new warts develop, they usually can be treated in the physician's office. Sometimes new warts develop so rapidly that office treatment may not be possible or could be quite uncomfortable. In these situations, a second, and occasionally, third outpatient surgical visit may be recommended.


How long is treatment usually continued?

Follow-up visits are necessary at frequent intervals for several months after the last wart is observed to be certain that no new warts occur. It is important to see your physician on a routine basis as recommended by her/him or if you notice any new lesions or new symptoms (pain, rectal bleeding).


What can be done to avoid getting these warts again?

In some cases, warts may recur repeatedly after successful removal, since the virus that causes the warts often persists in a dormant state in the skin. Discuss with you physician how often you should be examined for recurrent warts.

To prevent further spread of HPV, safe sex practices are recommended and include sexual abstinence, condom protection or limiting sexual contact to single partner. As a precaution, sexual partners ought to be checked for warts and other sexual transmitted diseases (STD), even if they have no symptoms. Your physician may also recommend that you be tested for other STDs.


What is anal dysplasia?

Some warts have abnormal changes seen by the pathologist when they look at the removed wart under the microscope.  These changes are called anal dysplasia and can be graded as to how advanced their dysplasia or abnormal changes are under the microscope. These changes are referred to by physicians as low-grade and high-grade anal intraepithelial neoplasia (LGAIN/HGAIN). Cells that are becoming malignant or “premalignant”, but have not invaded deeper into the skin, are often referred to as HGAIN. While this condition is likely a precursor to anal cancer, this is not anal cancer and is treated differently than anal cancer.  Anal dysplasia (LGAIN/HGAIN) is similar to cervical dysplasia (cervical intraepithelial neoplasia or CIN) in that it originates from a HPV infection and can develop into anal and cervical cancer, respectively.  Thus, patients with anal dysplasia need close follow up determined by their physician and any new lesions must be evaluated promptly. A gynecologic examination is also recommended in females, as the presence of HGAIN puts a female patient at risk for having CIN.



Who is at increased risk for anal dysplasia?

Risk factors for anal dysplasia include:

1.     Patients with HPV infections (most common)

2.     Patients with history of anal intercourse

3.     Positive HIV test

4.     Cigarette smoking

5.     Patients with a weakened immune system from certain medications (solid organ transplantation, RA, IBD)



Why do we need to treat anal dysplasia?


Once you have anal dysplasia, it rarely disappears.  Although still exceedingly uncommon, there is a slight increase risk of anal cancer in patients with a history of anal dysplasia (less than 5%). Its progression in HIV-positive patients seems to be higher.   The risk for progression to anal cancer may be as high as 10-50% among HIV-positive patients.



How is anal dysplasia diagnosed?


Anal dysplasia can be found in anal warts or sometimes these changes are found incidentally at the time of unrelated anal surgery (i.e. hemorrhoid surgery).


Screening procedures available to detect anal dysplasia include anal cytology and high-resolution anoscopy (HRA). However, they are not universally performed and their role in the management of patients with anal dysplasia is unknown at this time.


1. Anal Papanicolaou (Pap) smear cytology consists of using anal swabs to sample cells from the anal canal and can be used for both screening patients considered high-risk (see list above) and as follow up after anal dysplasia has been treated.  Unfortunately, up to 45% of patients can have a false-positive test by anal PAP for anal dysplasia.  As well,  it is not known if anal PAP improves your outcome or decreases your risk of anal cancer.


2. HRA typically involves the application of temporary stains (3% acetic acid and Lugol’s iodine solution) to the anal canal followed by evaluation under high-resolution microscopy to help differentiate normal from abnormal tissue. This is very similar to colposcopy (examination of the cervix) in women who have cervical dysplasia. Directed biopsies are performed for any questionable areas and to identify areas that may need further treatment.



How is anal dysplasia treated?


1.  Observation alone with close clinical follow-up may be considered for the treatment of anal dysplasia.  There has been much debate regarding the best treatment for anal dysplasia.  There is a high risk of recurrence following treatments so physicians may recommend close observation and physical examination every 3-6 months depending on your risk factors and if the screening procedures discussed are available in your area.    However, due to the high risk of also having cervical dysplasia, a referral to gynecology is recommended.


2. Topical 5% imiquimod (Aldara) cream or 5% 5-fluorouracil (5-FU) cream may be applied to areas of anal dysplasia. Local treatment creams may be needed for 9-16 weeks. Up to 90% may have anal lesions disappear, although as many as 50% can recur.  Local side effects are very common, occurring in up to 85%, and include skin irritation and hypo-pigmentation (loss of color around the anus), but these stop or reverse after you stop the cream.


3. Photodynamic therapy may be used in select patients. Similar to use in other types of skin cancers, photodynamic therapy has been described in patients with anal dysplasia since 1992. In this process, photosensitizing agents such as 5-aminolevulinic acid creams are applied to the affected area followed by treatment with a specific wavelength laser.  Studies have been limited and its role in patients with anal dysplasia is still unknown.


4. Targeted destruction and close clinical long-term follow-up.  A variety of surgical techniques to remove anal dysplasia have been used to prevent disease progression. These include wide local excision and targeted therapy using high-resolution anoscopy (HRA).  Wide local excision’s goal is to remove all of the affected areas with normal surrounding tissue (“negative margins”), although total removal of all disease is often difficult.  Sometimes a local flap of normal tissue adjacent to the removed area is used to cover the large defect.  There is still a high rate of recurrence of anal dysplasia despite a wide removal of tissue and high rates of complications such as stenosis anal (narrowing of the area) and fecal incontinence. Targeted destruction guided by high-resolution anoscopy is effective to identify, biopsy and destroy anal dysplasia without the long recovery and complications associated with wide local excision.  However, there is still a high risk of persistent or recurrent disease, reported in up to 20-80%.  Surgical complications such as incontinence and stenosis are generally not seen with HRA, though.  Fortunately, both wide local excision and targeted destruction by HRA have been shown to prevent progression from anal dysplasia to anal cancer.



How should I be followed after treatment for anal dysplasia?


Patients with anal dysplasia should usually be closely followed long term to prevent or  detect recurrence, persistence or progression to anal cancer.  Physical examinations may be performed at 3 to 6-month intervals. This approach allows for the treatment of recurrent or persistent dysplasia or the detection of anal cancer.  Follow-up generally includes digital rectal examination, anoscopic examination, with or without the aid of magnification or the application of acetic acid and Lugol’s solution, and can be performed in an office setting. Anorectal cytology (anal PAP) and/or biopsy may also be included if available in your area. The importance of close follow-up cannot be over emphasized in patients with history of anal dysplasia especially if new lesions develop.



What is a colon and rectal surgeon?


Colon and rectal surgeons are experts in the surgical and non-surgical treatment of diseases of the colon, rectum and anus. They have completed advanced surgical training in the treatment of these diseases as well as full general surgical training. Board-certified colon and rectal surgeons complete residencies in general surgery and colon and rectal surgery, and pass intensive examinations conducted by the American Board of Surgery and the American Board of Colon and Rectal Surgery. They are well-versed in the treatment of both benign and malignant diseases of the colon, rectum and anus and are able to perform routine screening examinations and surgically treat conditions if indicated to do so.





The American Society of Colon and Rectal Surgeons is dedicated to ensuring high-quality patient care by advancing the science, prevention, and management of disorders and diseases of the colon, rectum, and anus.  These brochures are inclusive, and not prescriptive.  Their purpose is to provide information on diseases processes, rather than dictate a specific form of treatment.  They are intended for the use of all practitioners, health care workers, and patients who desire information about the management of the conditions addressed by the topics covered in these brochures.  It should be recognized that these brochures should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results.  The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all the circumstances presented by the individual patient. 



author: Jennifer Lowney, MD, FASCRS, on behalf of the ASCRS Public Relations Committee 



© American Society of Colon & Rectal Surgeons