As a gay man, the last thing on your mind is a Pap smear. Pap smears test women’s cervixes for the presence of abnormal cells caused by the human papillomavirus, or HPV. But here's something important you might not know: Men who participate in receptive anal intercourse have far higher rates of anal cancer than the rates of cervical cancer in women—in part because they don’t think Pap smears apply to them. To fill us in on the facts on HPV, demystify the Pap smear, and offer some advice, we spoke to Dr. Raphael Landovitz, MD, an Assistant Professor in the Division of Infectious Diseases at the Center for Clinical AIDS Research & Education at the University of California, Los Angeles.
Men and HPV: Breaking Down the Numbers
Dr. Landovitz began with an HPV breakdown. He explained that there are more than 100 subtypes of HPV; only a few of these cause cancer. Others can cause warts. But over the last decades, Dr. Landovitz says, “It’s become clear that the same few predominant strains of HPV were causing anal cancer in HIV-positive men as caused cervical cancer in women.” Anal cancer from HPV is also common—though less so—in HIV-negative men who have receptive anal sex. And yet where most women are screened annually for HPV and cervical cancer, gay men tend not to know that they may need to be tested.
The numbers are not very encouraging. Ninety-five percent of HIV-positive gay men have some form of HPV. The New York Times reported last year that men who have receptive anal sex in general are at a high risk for anal cancer, which will be diagnosed at “an annual rate of about 35 cases per 100,000, and perhaps twice that for those infected with H.I.V., which weakens the immune system.” By comparison, this makes anal cancer rates among even HIV-negative gay men roughly equivalent to women’s cervical cancer rates before the advent of widespread screening via the Pap smear. That statistic implies the role the Pap smear (or another screening test) could have if it were more widely applied.
Prevention: Rethinking Safer Sex
Dr. Landovitz confirms that there is a link between becoming infected with HIV and HPV—basically, unsafe sex practices will lead to both kinds of infection. But gay men who practice safer sex are also at risk for HPV infection. HPV is transmitted to the anus by skin-to-skin contact—penile/anal (the most likely), oral/anal, or even digital-anal (finger in anus, or even sharing sex toys). And while condoms are a partial protection against the virus, they are far from perfect. “Condoms reduce the rate of infection," Dr. Landovitz says, "but are not 100% protective for HPV. Condoms don’t cover the entire penile shaft, and the virus can be transmitted from uncovered genital areas.” Since transmission requires only skin contact—rather than an exchange of bodily fluids, as in the case of HIV—a condom can only reduce transmission rates by lessening that contact, not by eliminating it. You can be safer, but not 100 percent safe.
By now you may already have a sense of whether you should be thinking about getting an anal Pap smear. Dr. Landovitz advises that, “The current recommendation of experts in the field is that MSM [men who have sex with men] and all HIV-positive men (and possibly HIV-positive women as well) should be routinely screened—meaning once a year.” The Fenway Institute in Boston likewise recommends anal Paps for all men who participate in receptive anal sex, regardless of their HIV status.
The Test: What to Expect
The anal Pap smear is a screening test; it provides a “snapshot” for where you are right now. So, it has to be repeated regularly even if you have stopped being sexually active—HPV and its complications can show up over time. In other words, just because it isn’t found the first time doesn't mean it’s not there. It may just be below the limits of detection of the testing.
Should you go in for the test, here’s what you can expect. A doctor will insert a polyester swab (think “Q-tip”) one to two inches into the anal canal, and scrape in a circumferential way (“like stirring a cookie batter,” as Dr. Landovitz vividly describes it), 10 times around, to collect cells. The cells from the scraping will then be examined under a microscope for abnormalities. The test’s accuracy depends on the expertise of the collecting physician, and the pathologist, who reads the smears.
Understanding the Results
HPV test results are not always cut and dry. Below are the possible outcomes:
Normal: There is the possibility that the test will come back completely normal—and that is obviously the most desirable outcome. Or, the sample may not be good enough to provide enough cells to be certain of a result, in which case the test will need to be done again.
ASCUS: The test may come back as ASCUS, which stands for “atypical cells of unknown significance.” This means that the cells do not appear 100 percent normal, and further testing is needed. Anoscopy will be the next step to make a more thorough diagnosis.
AIN: AIN stands for “anal intraepithelial neoplasia” and means that the test has found atypical cells on the skin surface. These cells are categorized by degree of abnormality, with 1 being the least abnormal and 3 being the most abnormal. Again, anoscopy is the protocol in such a case.
Either an ASCUS or AIN result requires further examination through High Resolution Anoscopy (HRA). As Dr. Landovitz (soothingly) describes, “In this procedure, a doctor uses a dilator to open the anus and looks for lesions, prepping the area with a solution that is taken up more by abnormal cells than normal cells, causing them to reveal themselves. The doctor will then biopsy anything worrying. In many cases, this procedure will remove the abnormality—in some cases, further treatment may be necessary.”
After an abnormal Pap smear, doctors will typically move to mandatory HRA every six months, skipping the Pap smear entirely. As Dr. Landovitz tells us, from here the protocol becomes somewhat unclear: “After a while you could probably get less aggressive—but after what time interval or set of repeated HRA findings has not been defined. This is still a young field, so a lot has not been defined.”
Warts and HPV
HPV also causes warts. These warts are non-cancerous, and can be frozen or burned off the body, or treated with imiquimod (Aldara), a cream that irritates the warts and persuades the body to fight them off. But anyone with warts on the exterior of the anus should go directly to anoscopy, even with a clean Pap smear, Dr. Landovitz says. “The rate of finding problems internally is so high in cases with external warts that an internal exam is very important.” In part, this is because 40 percent of people who have HPV have more than one type, and with warts in particular, having one strain is a predictor for having others.
HPV Vaccine: The Hope of the Future
You have probably heard of Gardasil, Merck’s vaccine for HPV, which was approved for use in the U.S. in 2006. Gardasil protects against four common cancer-causing strains of HPV, but does so only in people who have not been infected with those strains of the virus already, and it is approved for use only in women.
This situation may change shortly. Merck is currently running a trial of Gardasil in 4,000 men, 500 of them gay. Another study through the AIDS Malignancy Consortium (AMC) will start soon testing Gardisil with HIV-positive men, Dr. Landovitz says, and one is already going on at the AIDS Clinical Trial Group (ACTG) testing Gardisil on HIV-positive women, some of whom are already infected with some strains of the virus. All of this is intended to tease out the gender and immunological implications of Gardisil. “There are immunologic differences between men and women—cyclical hormonal changes, for example," says Dr. Landovitz, "so we don’t know what will happen with the vaccine in men. No one may expect a difference; but one may very well be found—we really need the science to understand the practical use.” Until there is a vaccine approved for use in men, vigorous screening and treatment are the only real options.
Know Your Doctor
If you think you may be at risk for HPV and anal cancer, you should speak to a physician about the possibility of being screened. But make sure you talk to the right kind of physician. Dr. Landovitz says strongly that, “HIV-positive men must see an HIV expert; and HIV-negative men need to see a doctor who is expert in LGBT issues and knows the correct test and how to interpret the results.” To find a gay doctor, ask friends who might know or check out the Gay and Lesbian Medical Association’s referral service to look for a physician sensitive to LGBT health issues. Because this is a developing field of research, you need a doctor who’s familiar with the recent literature, and has the equipment, training, and expertise to address LGBT health issues, even if you’re HIV-negative.