Dr. Joel Palefsky is an expert in infectious diseases and cancers related to these diseases. He is an internationally recognized expert in anal and genital human papillomavirus (HPV) infections and specializes in people living with HIV. He recently led it Rectal Cancer/HSIL Outcomes Research (ANCHOR) Study.a multi-site study that looked at whether detecting and treating precancerous lesions could prevent rectal cancer.
Dr. Palefsky is the founder and president of the International Anal Neoplasia Society as well as the founder and president of the International Papillomavirus Society’s global HPV awareness campaign.
ASHA recently met with Dr. Palefsky to talk about HPV and anal cancer.
Can you explain what rectal cancer is and who often gets it?
Anal cancer is very similar to cervical cancer and is caused by the same types of HPV. It is still a fairly rare disease, but the incidence has been increasing since the 1970s.
It is more common in women than men in the general population, but there are certain groups known to be at particularly high risk. These include people with HIV and women with a history of vulvar and cervical cancer. Men who have sex with men—particularly HIV-positive MSM—are the highest-risk group.
You said anal cancer is caused by HPV. Is initial HPV infection usually a result of anal sex?
It is not always. About half of the women in many of the studies that have been done had never had anal sex. These people probably contract anal HPV from cervical or vulvar infections. The other half had anal sex, which is a common sexual practice.
This is probably one of the reasons why anal cancer is more common in women than men, because women have more opportunities to get HPV. But, again, those who have more anal sex, ie MSM, have a much higher risk of anal cancer. When you throw HIV on top of that, it increases the risk even more.
How do people usually find out they have rectal cancer?
Because there’s no control for it, most people don’t seek help until they experience symptoms—usually bleeding, pain, or a mass they can feel. The typical story for someone not known to be at risk is that they go to their doctor for rectal bleeding and are told they have hemorrhoids. Sometimes they even do surgical hemorrhoids, and when the pathology returns, they find out that it is cancer.
Is there a way to find precancerous cells like we do with the Pap test for cervical cancer?
There are screening tests that are similar to the ones we use for cervical cancer. We can swab the area and check for precancerous changes with a cytology test, and sometimes we can also test for HPV.
There is also a procedure called a high-resolution anoscopy, or HRA, in which we examine the anal canal with a high-resolution instrument called a colposcope. We visualize the entire anus using the same stain we use on the cervix – acetic acid – and take biopsies to see if they have precancerous anus [called high-grade squamous intraepithelial lesions] and rules out cancer.
If the biopsies come back showing, we repeat the process but this time the approach is usually to use electrocautery. We use a version called hyfrecation in which we try to remove the affected area but lose as little of the normal tissue as possible. It is done in the office and is a quick, 20 minute procedure that is very well tolerated and not painful.
You just completed something called the ANCHOR study where you were trying to test whether treatment for precancerous cancer helped reduce rectal cancer. What were the results?
The Study ANCHOR included nearly 4,500 participants with HIV. It was not a screening study because one of the key entry criteria was biopsy-proven high-grade disease [anal pre-cancer]. We performed HRA in all study participants because it is the gold standard diagnostic procedure. And as it turns out, that’s a good thing we did because what we found was an extremely high prevalence of these high-grade lesions. About half the population had these high-grade changes.
The real goal of the study was to show that we could significantly reduce the incidence of rectal cancer by treating the precancerous cancer, and we did this even before we completed recruiting for the study. It was a randomized controlled trial. Half the people were treated and half were untreated.
We follow up to make sure that people who were not treated were offered the opportunity to receive treatment and continue to follow the people we had treated before. All clinical follow-up has just ended.
To treat precancerous cancers, you need to screen for them. Who should be screened for rectal cancer?
CDC to issue guidelines for rectal cancer screening using cytology and HRA. These are mostly limited to people with HIV because that’s where the research has been done. There are other guidelines recently published on International Journal of Cancer which add some other high-risk groups to those that should be screened in this way.
We do not recommend that everyone be screened this way because rectal cancer is rare. The risk to the general population is very low. But our next step should be to strengthen the infrastructure so that more places have providers who can do HRA. Right now it is concentrated in cities with large MSM populations, but there are many communities in the United States where no one knows how to do this.
We recommend everyone get one digital rectal examination. We call it DARE. People are more familiar with digital rectal exams [in which a health care provider inserts a gloved finger into the anus/rectum]. These are mainly aimed at finding rectal cancers. We want to make sure that providers also focus on the anal. The purpose of DARING is to feel things like hard lumps that may indicate the presence of cancer, but you can’t feel precancerous.
Does the HPV vaccine prevent anal cancer?
I published the first paper showing that the vaccine worked to prevent anal HPV. This actually gave the vaccine approval for boys. The vaccine is the best long-term answer: if everyone in the current vaccine classes got the vaccine, anal cancer and cervical cancer would be a thing of the past. But it will take decades for that. Anal cancers grow even more slowly than cervical cancers because it takes longer for HPV infection to develop into cancer.
Everyone who can be vaccinated should get the vaccine. The point though, is that there are many people who have not yet had the vaccine or are too old to be vaccinated. This group needs screening beyond vaccination.
Is there still a stigma around anal sex, do you see this affecting your patients?
I think the answer to that varies a lot by demographic. A fairly high percentage of my patients are gay men, and while there is still some stigma in this population, it is generally not as noticeable as with some of the other groups I see in the clinic. For example, I have several female patients with rectal cancer and they often tell me how difficult it is to talk about the disease to their family and friends.
HPV is stigmatized, cancer is stigmatized, and we don’t like talking about the anus at all. It’s like the triple smile. I often refer my patients to Rectal Cancer Foundation which can provide additional emotional support.
They also run a global HPV awareness campaign every year. Can you tell us about it?
HPV Awareness Day is March 4th. The main message is that HPV is very common and we are all affected by it. If you haven’t, you know someone who has. We want to make it part of the normal conversation and encourage vaccination among anyone who qualifies and screening for anyone who is eligible for it.
The theme of the campaign is ‘One Less Worry’. One of the things we emphasize in the campaigns is that we do have a message of hope here. We have everything we need right now to make cervical cancer and rectal cancer a memory. Not immediately, but for the next generation.
