Human Papilloma Virus (HPV) is a recognized cause of cervical, vaginal, and vulvar cancer. For younger women, there is now a recommendation for a three-part vaccine (Gardasil) that may protect against two of the many forms of the high-risk strains of HPV. (Young men have not been advised to have this vaccine as yet.)
The FDA approved the use of the HPV vaccine to prevent anal HPV. But the FDA has not yet approved the use of this vaccine to prevent HPV at all in women over the age of 30.
Here's why: as women age, our immune systems are no longer as effective in responding to vaccinations such as Gardasil. Women exposed to HPV when older are less likely to eradicate this carcinogenic virus from their body because of a less effective immune system. In addition, auto-immune and other illnesses, along with some drugs, can impede the body's ability to eradicate the virus.
In an article in the New York Times earlier this month, Roni Caryn Rabin wrote about a 51-year-old mother of three children who had been treated for cervical dysplasia (pre-cancerous cells usually caused by HPV) in her 20s. She was diagnosed with anal cancer at a late stage, and died from the disease in April 2010. Here at WVFC, HPV has been a topic of discussion because of the virus' impact on women over 40. With that in mind, we asked colo-rectal surgeons Dr. Alex Jenny Ky-Miyasaka (of New York's Mount Sinai Hospital) and Dr. Kelly Garrett (of New York Presbyterian Hospital) for their opinions on the current lack of evaluation guidelines, and what this means for women at our time of life.
Alex Jenny Ky-Miyasaka, M.D.:
HPV (human papilloma virus) is a common virus, and the main cause of anal cancer. More than half of the population who are sexually active have been exposed to HPV at some point in their lifetimes. There are a lot of different types of HPV, but a healthy immune system usual keeps us from getting an active infection.
Women have been benefiting from early detection of cervical cancer from their annual pap smear for decades. This has helped with early detection and minimally invasive treatment before the infection spreads, which requires much more radical surgery and treatment.
More recently, the anal equivalent of a pap test has also been utilized for early detection of squamous cell carcinoma of the anal canal, primarily in men who have sex with men. The anal canal is like a tunnel that goes from the inside (rectum) to the outside. We need to expand this early detection to include not only men who have sex with men, but others at higher risk. These include both men and women whose immune systems are suppressed from HIV or medication for transplant, and those who participate in anal sex, have multiple sexual partners, or have a history of HPV.
The anal pap test is similar to the cervical pap test for women. It does not hurt and very often does not cause any discomfort. A small swab is placed in the anal canal, and cells are collected. The cells are examined under the microscope for unusual changes. Cell changes don't necessarily mean cancer, but a high-resolution anoscopy is recommended. This can be done in the office, or preferably in the operating room with a little sedation, which is much more comfortable for the patient.
The results can come back as AIN I, II, or III. AIN I is low-grade cell dysplasia, with III being high-grade dysplasia. These cells can be excised and sometime also treated with infrared coagulation with little, if any discomfort.
If a diagnosis of cancer is found, this is often treated not with surgery, but chemotherapy and radiation.
Most patients with anal cancer do not have symptoms. Some might have a little bleeding and attribute this to "hemorrhoids." Others might have pain and irritation but again may blame it on hemorrhoids or a fissure. It is hard to see the anal canal on your own!
The screening is simple and painless. We need to expand and recommend screening for anal cancer to include not just men who have sex with men, but all of those who are at a higher risk.
No one likes to go in to have their bottom looked at. But it is better than dying from a very preventable cancer.
Kelly Garrett, M.D.:
With respect to Paulette, the woman in the New York Times article--could her cancer have been prevented or caught earlier? Possibly. But to date, there are no national screening guidelines for anal cancer in the United States.
In the HIV-negative population, squamous cell cancer of the anus is rare. The National Cancer Institute estimated that 5,260 patients would be diagnosed with anal cancer in 2010, and that 720 men and women would die of the disease. Although significant, this is less than the estimated 140,000 new cases of colo-rectal cancer with 50,000 deaths per year.
Like cervical cancer, anal cancer is preventable if caught in the early stages.
Human PapillomaVirus (HPV) can be linked to both cervical and anal cancer. We know that an infection can cause genital warts or precancerous changes, depending on the type of HPV virus that is present. The progression of precancerous changes involving the cervix has been well documented, but the progression of high-grade anal intraepithelial neoplasia (AIN) to invasive disease still needs to be better understood.
Although some specialists recommend screening in high-risk populations (HIV-positive men and women and HIV-negative men who have sex with men), there are no formal national guidelines for average-risk populations. Dr. Joel Palefsky and his group at UCSF have done the most research on this topic. In a study looking at a very healthy group of young women, they found that about 60 percent of them had anal HPV infection, compared to about 50 percent or so in the cervix. In a study done in a similar group in Hawaii, the prevalence was very similar. In other words, anal HPV infection in women may be far more common than anyone may have imagined. What this means from an oncologic standpoint still remains to be determined.
The New York Times article about the Crowthers family begs the question, Should every woman have a screening anoscopy with her cervical pap smear? From an evidence-based perspective, this form of screening is not supported by any literature. But it certainly does seem reasonable to offer women with a history of HPV and abnormal pap smears a screening anoscopy.
The obvious goal of developing screening guidelines for anal cancer is to identify and treat both early cancers and high-grade AIN. At this time, no randomized clinical trials have been done to validate the use of any screening protocols. In 2007, the New York State Department of Public Health AIDS Institute recommended an ano-rectal examination and pap smear at baseline and annually in HIV-infected men who have sex with men, in any patient with a history of ano-genital condyloma (warts), and women with abnormal cervical pap tests. As a starting point for development of a universal screening guideline, perhaps the New York State recommendations should be adopted nationally. This would increase awareness of the disease and hopefully give us a clearer picture of its natural history, by allowing us to better study larger groups of early cases.
Patricia Yarberry Allen, M.D.:
Although it has not been documented rigorously, there is a reason to believe that anal cancer could develop very much the way cervical cancer does. The change in the cells begins with mild atypica, progresses to more serious abnormal change (mild, moderate and severe dysplasia), before developing into frank anal cancer. Doctors have known about the relationship of HPV and anal cancer from long experience with gay men, who have a high incidence of this cancer due to receptive anal sex practice. We need the expertise of these physicians, now that HPV has been recognized to be a growing concern for women and recognized as a cause of cervical, vaginal, and vulvar cancer and is now publicly discussed as a cause of anal and oral cancer.
It is important that colo-rectal surgeons develop expertise in high-resolution anoscopy and an interest in recognizing abnormal change at an early stage. Gynecologists are specially trained in colposcopy to view and recognized abnormal cellular patterns that can be biopsied, diagnosed, and treated. It takes time and training to become very good at these procedures.
At the moment, there is no consensus among our specialities about how to monitor for and evaluate the presence of anal HPV. An HPV swab test can be done in the anal area. Pap smears can be done in this area. But there are no national guidelines for primary care doctors about when to do these tests, and no guidelines about what to do with the results. We don't have a treatment protocol for anal dysplasia that is universally used.
The result is that women with high-risk HPV of the genital area are almost never tested for anal HPV, even if the woman expresses concern about her risk. That means that cells that could be treated earlier, before there is frank malignancy, are not found.
We don't want women to wait for a diagnosis until they have rectal bleeding or a feeling that there is a constant fullness in the anal area. These are symptoms of many benign diseases but also the symptoms of anal cancer. We have to have a plan based on what is known and what evaluations are available.
We can no longer ignore the reality that this virus is a cancer-causing virus, and that women who have it must be screened appropriately. Women who are positive on more than one occasion with high risk HPV infections and have cervical dysplasia should ask for anal HPV testing and an anal pap test, and if their doctors refuse to perform them, find doctors who will. "We don't know what to do with the results of a positive test for high risk anal HPV" is no longer a sufficient response.
As in so many areas of medicine, early diagnosis means improved treatment options, and in most cases, avoidance of cancer. The good news, so far, is that the numbers of anal cancer cases are still small. The virus can be spread to the anal area from the scrotum without receptive anal sex, but based on current knowledge, receptive anal sex must be considered a higher-risk practice. Women can decrease their risk of anal cancer by limiting the number of sexual partners, and always -- always-- using condoms.