In 2014, Daniel Garza, a comedian and sexual health advocate, was experiencing constipation and slight bleeding from his rectum. Still, his primary care doctor didn’t think it was a big issue and suggested laying off spicy Mexican food. The problems persisted, and it wasn’t until a follow-up from an unrelated hernia surgery that the operating surgeon became concerned about a growth in Garza’s anal sphincter. It was cancer, and the diagnosis came on Cinco de Mayo, 2015, something that Garza, being Mexican, found ironic.

Anal cancer is rare in the general population, but it’s one of the most common cancers affecting gay and bisexual men.

There were anal polyps as well, which the doctor believed resulted from unprotected anal intercourse when Garza was younger. The cancer very likely came from the same sexual activity, through the human papillomavirus (HPV). The practice of bottoming without protection also led to HIV, which Garza learned about years earlier, but not until his T cells were well under 200.

“The polyps, HIV and HPV basically got together and caused cancer,” Garza said.

Anal cancer is a big risk for bottoms

Anal cancer is rare in the general population, but it’s one of the most common cancers affecting gay and bisexual men. In fact, gay/bi men or individuals who identify as men who have sex with men (MSMs) are 20 times more likely to develop anal cancer than heterosexual men. The reason is HPV, which can be transmitted through bottoming, from the penis to the anal canal.

More than 90% of anal cancers are caused by HPV, specifically one strain: HPV-16, which can cause anal and genital warts. Millions of people acquire some strain of HPV every year and in most cases the immune system can fight it and clear it from the body. People with suppressed immune systems (unsuppressed HIV for example) are less likely to clear the infection.

There are vaccines to prevent HPV infection, and they’ve been approved for boys and men between ages 9 and 45 years. The thinking behind the age cutoff is that by midlife most men have had the bulk of their sexual partners and therefore have already been exposed to many strains of HPV. Most insurers won’t cover HPV vaccination if you’re over 45, so if you’re older a full series of three shots could run $1,000-plus out of pocket. Some doctors say getting the shots later in life is still worth it, if you can afford it.

Using condoms for anal sex, a practice more common during pre-PrEP days, can also reduce the risk of HPV and other STIs. PrEP, while highly effective at preventing HIV transmission when used as directed, is only effective at preventing HIV, not other STIs.

If you’ve ever bottomed and never been tested for anal cancer and especially if you have HIV, it’s a good idea to ask your doctor to screen for it. There are three key screening tools for detecting abnormal or pre-cancerous lesions in the rectum:

Digital rectal exam, where the doctor inserts a gloved finger into the anus to feel for lumps or warts. A doctor can also explore the prostate for abnormalities this way.

Anal cytology or Pap smear, which collects cells from the anus to be examined in a lab.

High resolution anoscopy, where a small microscope is attached to the end of a plastic tube, which is inserted into the anus. If the microscope finds an abnormality, a biopsy can be taken.

A recent study showed that it’s possible to diagnose, through a Pap test or high-resolution anoscopy, and treat abnormal cells in the anus before they develop into later stage cancer.

But doctors are not likely to automatically screen for anal cancer, according to Alan Nyitray, an associate professor of psychology and behavioral medicine at the Medical College of Wisconsin.

“There are a lot of barriers to anal cancer screening, and no national consensus recommendation to screen,” Nyitray said. He added that doctor-patient conversations about anal cancer risk aren’t happening.

“Even for people with HIV, their HIV docs don’t bring up anal health much, which is important because people with HIV are at much higher risk of HPV and anal cancer,” he said. “A lot of providers are not comfortable doing an anal exam. There is a lot of stigma associated with the anus.”

Nyitray suggested that MSMs educating themselves on the risks of HPV, and advocating for home testing, could make a positive impact on anal cancer rates. He authored a recent study to learn whether people would be likely to engage in screening for anal cancer if they received an at-home kit or if they got screened at a clinic.

For the study, 240 participants—both cis and trans men plus trans women—were randomized into two arms: one in which they had to call one of five clinics to request an anal cancer screening appointment and show up for it, and the other group took the at-home test.

Nyitray found that people who got the kit at home were more likely to engage in screening: 89% returned the kit versus 74% who made an appointment at a local clinic and had the swab done there. Those results were what Nyitray expected, but he was surprised at how important home testing is for people who are Black. In the home-based arm, 96% of Black participants used the home test but only 63% accessed the clinic. Nyitray speculates that the reasons for the disparity are lack of access to nearby health care or not having health insurance. “Medical mistrust (among Black people) is one reason for much lower engagement in health care settings.”

Nyitray added that home testing for anal cancer was cost-effective. “There wasn’t one person in the home-based arm who said they had to miss work, but a lot of people in the clinic arm had to miss work.”

Being an advocate for your bum

HPV vaccines were not available when Daniel Garza was younger. Now 53, Garza uses an ostomy bag due to the removal of most of his sphincter. The bag is a lifesaver he admits—he’s cancer free—but definitely inconvenient and not ideal.

In addition to being a stand-up comic, Garza does presentations on HIV and HPV at community colleges, universities and high schools where he shares very personal details about his butt. The most important thing he emphasizes for young men is protection, which means not just PrEP, but condoms—something that MSMs have been increasingly resistant to using. 

“If (your anus) hurts or if you're bleeding, go to the doctor to get checked. And all young men should get the HPV vaccine,” Garza says.

It takes some fortitude to initiate delicate conversations about sexual practices and personal risks of HPV and other infections if the doctor doesn’t bring it up. 

Asking for the vaccine or anal cancer screening requires being a self-advocate.

“Even if your doctor is gay, don’t assume they will understand what you need,” Garza said. 

Daniel G. Garza trades observations with fellow comedian Andy Feds, who was born with HIV. READStandup act.”

It’s not all about anal sex

To be clear, you don’t need to have anal sex to get anal cancer—especially for women.

“Some people suggest that if you have a history of anal sex you may want to get checked for anal HPV, which is correct. But studies suggest, and this is particularly true for women, that history of anal intercourse is not a strong risk factor for anal HPV,” said Jessica Wells, PhD, RN, an associate professor at the Nell Hodgson Woodruff School of Nursing at Emory University. “For women, this is due to the geographic location of the cervix to the anal canal. A lot of times cross-contamination occurs. So if a woman has a history of cervical HPV, just due to the proximity of the anal canal, she is also at risk of anal HPV.”

Human papillomavirus (HPV) is the most common sexually transmitted infection, according to the Centers for Disease Control and Prevention (CDC).

Dr. Wells explained, however, that, "People living with HIV have a significantly higher incidence of anal cancer." She called the rate "alarming."

In the general population, she noted, anal cancer is very rare, about eight cases per 100,000 persons.

However, she added, “Reports have shown on average 60.1 new cases per 100,000 among men and women living with HIV. And men who are same-gender-loving have an even higher increased risk for HPV, with reports as high as 141 cases per 100,000."

To be clear, you don’t need to have anal sex to get anal cancer

The CDC recommends HPV vaccination for individuals who are immunocompromised, including people living with HIV, cancer survivors and transplant recipients.

“HIV and HPV are both sexually transmitted viruses, so co-infection is common. One study found that anal HPV among a sample of women was actually more prevalent than cervical HPV. Additionally, studies have shown that HIV-positive individuals are more likely to have persistent HPV infection. It’s that persistent HPV infection, coupled with being immunocompromised, that drives the increased risk of HPV-related anal cancer,” she said.

Other risk factors associated with anal cancer include smoking, a history of anal intercourse, [a higher] number of lifetime sexual partners, history of other STIs and history of HPV or dysplasia (abnormal cells).

The answer is to vaccinate. Vaccinate. Vaccinate. Vaccinate. Get the three vaccine shots that safely and effectively prevent several types of cancer, including anal. Gardasil-9 is the only HPV vaccine in the U.S.

Dr. Wells describes additional details, including how to easily and quickly get vaccinated for free, in her March presentation for the community HIV education series THERAThursdays from Theratechnologies. GO TO

She also explains how anal Pap tests are done and walks you through the anal canal. No, a colonoscopy will not help find anal cancer.

HPV can cause cancer of the cervix, a section of cells between the vagina and the uterus. Cervical cancer is an AIDS-defining illness.

Information about the subject isn’t getting out because people are uncomfortable talking about anal sex or anal cancer, and that includes medical providers. Dr. Wells discusses strategies for this as well.

As a researcher, Dr. Wells invites clinics to reach out to her to address anal cancer in the HIV community.

To view the presentation, GO TO

—Enid Vázquez