You Want To Stick That Where? A Guide to the Anal Pap Smear Before, During, And After…
What is the Pap smear?
Your healthcare provider has recommended that you get an anal Pap smear. This simple, painless, inexpensive test is a way to screen for abnormal pre-cancerous cells that may line your anal canal. Physicians have long realized that infection with Human Papilloma Virus (HPV) is an important precursor to the development of cervical cancer and more recently that the same mechanisms are likely responsible in the development of anal cancer as well. The HPV infects the lining of the cervix and anus (and also less commonly the urethra and throat) and can cause mutations which, over time, can transform normal cell lining into cancer.
For close to 60 years, the Pap smear has been used in women to screen for precancerous changes in the cervix. This major public health initiative has single-handedly reduced the rates of cervical cancer by over 600%. Over the last 15 years, rates of anal cancer have been going up particularly in men who have sex with men (MSM), but across all other demographic groups as well. The adoption of the anal Pap smear as a piece of a routine health exam has increasingly been gaining favor as the true scope of this problem has become better recognized.
Where does HPV come from?
HPV is considered to be the most common type of sexually transmitted disease. There are hundreds of known strains that can cause a wide spectrum of illness ranging from common plantar warts, to genital warts to cervical and anal cancer. The majority of us are likely infected with at least one if not multiple types of HPV and many of us will never manifest a single wart. The virus can be carried on any surface including but not limited to the mouth, hands, penis, anus and vagina. Most men will carry HPV on their penis at some point in their lives without knowing it. The virus can spread from any skin to skin contact which is why condoms reduce but can’t completely prevent the spread, as it would be rare for the virus to only live on the shaft and nowhere else. Condoms remain the best protection against the transmission of many diseases so don’t stop using them because you found a wart on your penis.
Simply having HPV doesn’t mean you will ever get sick. The strains of HPV are generally divided into low-risk and high-risk subtypes. The low-risk types are rarely dangerous (just annoying) because they are the ones most responsible for causing warts. Fortunately these warts will not turn into tumors and only about 1 in 5 with low-risk HPV will develop warts.
The high-risk types of HPV have the potential to transform normal squamous cells (cells lining the tracts of your anus, cervix, urethra, and oral cavity) into cancer cells.
Fortunately again, the vast majority of people harboring the high-risk subtypes will never have this problem. A small proportion of people with high-risk subtypes will develop precancerous cells and an even smaller percentage of people with pre-cancerous cells will develop full blown cancer
So what’s the big deal?
Unfortunately we have not been able to come up with a good way to predict who will or won’t get cancer. We know that the longer you have HPV, the greater the risk is that you can develop anal and cervical cancer. We also know that HIV-positive people are at greater risk than HIV-negative people and that while many of the AIDS related cancers like Kaposi’s sarcoma have gone down since the introduction of antiretroviral therapy for HIV, anal cancer rates have gone up
Who should be getting anal Pap smears?
When it comes to deciding who should get a Pap smear and how often, we look to our Ob-Gyn colleagues for assistance. HPV is so prevalent in the general population that all sexually active women are counseled to undergo routine lifelong Pap smear surveillance. Within the gay population, the prevalence of HPV is even higher (60-70% of HIV-neg MSMs, and close to 100% of HIV-pos MSMs), and it follows that a man who has shared intimacy (not necessarily sex) with another man should be getting screened routinely. To put it simply, anal cancer rates in gay and bisexual males is higher than cervical cancer rates were in all women before the introduction of the Pap smear. Combine that with the fact that anal cancer is highly curable when found early and the real question is why you haven’t had one yet!
In addition to MSMs, anal cancer rates have been increasing in some other groups as well, including lesbians, intravenous drug users, and immunocompromised people such as HIV positive men and women and organ transplant recipients.
What exactly is the anal Pap smear?
As opposed to polyps in the colon that can be slow growing for years before they turn into colon cancers, the early precancerous changes in the anus and cervix are often so subtle that they can’t be seen or felt. The Pap smear is a way to pick up abnormal cells long before they have the chance to complete the transformation to cancer.
The test itself involves inserting a soft cotton swab into the anal canal which is swiveled around to pick up cells which can then be transferred through a liquid onto a glass slide. A pathologist who specializes in looking at cells under a microscope can then examine the slide and asses the presence of any abnormal cells. The test can be done by anyone trained in the technique and is often painless of just a little “scratchy.” You may see a little blood with bowel movements. No special care is necessary following the test.
Will the test tell me if I have cancer?
You should get a call about your results within one to two weeks, and if you don’t you should contact your health care provider. Unfortunately, the Pap smear is not perfect and only in very rare and unusual circumstances will a diagnosis of cancer come back. Most of the time, the Pap will come back with one of 6 possible diagnoses. They will be discussed in detail below. Any abnormal test should undergo additional testing by a colorectal surgeon called High-Resolution Anoscopy (HRA). Occasionally you might be counseled to undergo an HRA because of some abnormal finding that was seen or felt on the initial exam.
So what did the test tell us?
The following are a list of agreed upon results that may come back in order to aid in diagnosis. These classifications are based on experiences with millions of cervical Pap smears in women
Benign – The cells are completely normal. You should resume screening with future Paps at intervals from every 6 months to 2 years depending on your other risk factors. This will be determined by your health care provider.
Unsatisfactory – Not enough cells were picked up on the swab and the test should be repeated.
ASCUS (Atypical cells of undetermined significance) – This designation basically means that there’s something unusual, yet not strange enough to call abnormal or precancerous. Often these don’t represent anything more than some underlying inflammation or irritation from a hard bowel movement or recent enema. HRA is indicated and can determine whether a real problem exists or not.
LSIS (Low grade squamous intraepithelial lesion) – These cells are abnormal and usually caused by the presence of HPV or warts. Occasionally they may be associated with precancerous changes and HRA should definitely be performed.
HSIL (High grade squamous intraepithelial lesion) – These cells again are most likely caused by HPV but now are showing considerable changes and indicate that you probably have a precancerous area present. HRA must be performed but it is important to remember that this does not mean you have cancer.
Anal Squamous Cancer – As mentioned above, this is a very, very rare occurrence but it implies that the cells have undergone the entire transformation to cancer and you must have immediate HRA.
What is an HRA?
HRA is analogous to colposcopy, a procedure often performed by an OB-GYN for abnormal cervical Pap smears. We know that suspicious areas in the anus will absorb vinegar and not absorb iodine, so using a microscope that can look into your anal canal, we instill weak vinegar for a minute and then iodine and look for abnormalities. Both the vinegar and iodine are usually painless and the only pressure you will feel will be from the anoscope going in and out. If any of these areas are identified, we will take a small biopsy which you may not feel at all or at worst a small pinch. If we need to biopsy any area on the outer anal skin, you may need a little local anesthetic. The procedure should take less than 20 minutes and you can often go back to work unless you needed conscious sedation. Any biopsies taken will be sent to the pathologist and evaluated. If precancerous lesions or warts are found you may be scheduled for further treatment.
Ok, I get it, what do I do now?
For a number of reasons, the nature and behavior of HPV and anal cancer has not received the attention that many other STDs have. The numbers of gay men affected by HPV and anal cancer is staggering, yet many men are completely unaware until their first genital wart or worse, their first abnormal Pap smear. If your doctor isn’t offering this test ask them why not, and after reading this fact sheet, if you, your partner, or your friends haven’t gotten tested, ask yourselves, “why not?”
Anal Pap smears are quick and painless.
Anal cancer is not.