Anal Cancer Risk Factors and Prevention
Anal cancer screening guidelines exist now. Most people who qualify have never been offered one. Here's who should be screened, and when.
Anal cancer screening starting ages by risk group, from the International Anal Neoplasia Society consensus guidelines.
| If you are | Screening starts at |
|---|---|
| A man who has sex with men, living with HIV | 35 |
| A transgender woman living with HIV | 35 |
| Anyone else living with HIV | 45 |
| A man who has sex with men, HIV-negative | 45 |
| A transgender woman, HIV-negative | 45 |
| History of vulvar precancer or vulvar cancer | Within a year of that diagnosis |
| Organ transplant recipient | 10 years after your transplant |
Usually once a year after that. Your provider sets the interval.
Not on the list? If you've had cervical or vaginal precancer, perianal warts, or your immune system is suppressed for another reason, ask whether screening makes sense for you. Your risk is up, and the guidelines call for a conversation rather than a set age.
Have symptoms? Then the ages don't apply to you. Bleeding, a lump, pain that won't settle, or a change that's sticking around needs looking at now, at any age. That's a faster conversation than this one.
A colonoscopy is not anal cancer screening. The scope passes through the anal canal but isn't looking at it. A clean colonoscopy tells you about your colon and nothing about anal cancer. Two separate screenings.
What happens during screening?
Less than you're likely picturing.
A gloved finger, about a minute, feeling for anything firm. A swab inside the anal canal, a few seconds, sent to a lab. That's the whole screening. No prep, no sedation, no driver, back to work after.
If exams are hard for you — bad experiences with providers, dysphoria, assault — say so before you start. Ask them to go slowly and narrate what they're doing. Ask for a provider of a specific gender. You can stop at any point. Someone who handles that badly has told you something useful about whether to go back.
If something comes back abnormal
Abnormal doesn’t mean it’s cancer. The next step is high-resolution anoscopy, or HRA: a magnifying scope, 15 to 30 minutes, you're awake. Most people describe pressure rather than pain. They biopsy anything suspicious.
Common anal Pap and HPV test results, and what each one means.
| Your result | What it means |
|---|---|
| ASC-US | Slightly off, significance unclear. Most common, least alarming |
| LSIL low-grade |
Usually an active HPV infection. Often clears on its own |
| HSIL high-grade |
Not cancer, but the stage worth treating |
| HPV positive | A high-risk strain is present. Very common on its own |
Treating HSIL is an office procedure. Usually electrocautery after the area is numbed. Minutes, not hours. You're awake, there's no hospital stay.
Expect soreness for a week or two, some spotting, and discomfort with bowel movements. Hold off on receptive anal sex while it heals. Ask for how long, it depends on how much was treated. HSIL comes back sometimes, which is why you stay on a monitoring schedule rather than being discharged.
If it is cancer: found early, anal cancer is highly treatable, usually with chemotherapy and radiation rather than surgery. Our treatment overview walks through it.
Actually getting screened
The guidelines are real. The system to deliver them is spotty.
The swab is the easy part. Any provider can do it. Ask at your next visit: "Based on my risk, should I be screened for anal cancer?"
HRA is the bottleneck. Only about 104 clinicians in the country perform it, and there's no national directory yet — the society that wrote the guidelines is building one. Until it exists, try an HIV clinic, an LGBTQ+ health center, or a colorectal surgery practice at an academic medical center. Ask: "Do you do high-resolution anoscopy, or who do you refer to?" Ask before you need it, not after.
Cost varies more than it should. Because no US government body has issued a formal recommendation, this doesn't automatically get the free-preventive-care treatment colorectal screening does. Plenty of plans cover it, especially for people with HIV, but it isn't guaranteed. Get the billing codes from the clinic and call your insurer with them. Ryan White programs cover a lot for people with HIV, and Federally Qualified Health Centers work on a sliding scale.
If a provider tells you anal cancer screening isn't a thing: it is, as of 2024, with published international guidelines. You can say that out loud. You're not being difficult.
Why this is new
Until 2022, nobody had proven that finding and treating anal precancer actually prevented cancer, so there was nothing solid to build screening programs on. Then the ANCHOR study followed more than 4,000 people living with HIV who had precancer, treated half of them, and found substantially fewer cancers in the treated group. It stopped early, because continuing to withhold treatment from the other half was no longer defensible.
The International Anal Neoplasia Society published the first consensus screening guidelines in 2024. That's where the table at the top comes from.
Two things worth knowing. The US Preventive Services Task Force hasn't issued a recommendation — they looked at the topic and set it aside, and it isn't under active review. And ANCHOR proved that treating precancer prevents cancer; no trial has yet shown that screening programs lower death rates. The guidelines rest on strong evidence about who's at risk and strong evidence that treatment works, with the step between reasoned rather than proven.
One thing that may fix the access problem: researchers are testing anal swabs you'd collect at home and mail in. Still research, not something you can order yet, but it's the most promising answer on the table.
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IANS Anal Cancer Prevention Screening Toolkit The society that wrote the guidelines, with patient-facing explainers and flowcharts. A provider directory is in development here. https://iansoc.org/Anal-Cancer-Screening-Tool-Kit
HPV and Anal Cancer Foundation Patient support, treatment information, and help finding care. https://www.analcancerfoundation.org
HHS Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV The federal guidance your HIV provider works from. The HPV section covers anal cancer screening. https://clinicalinfo.hiv.gov
HRSA: Find a Health Center Sliding-scale care if you're uninsured or underinsured. https://findahealthcenter.hrsa.gov
LGBTQ+ Healthcare Directory Find a provider you won't have to educate. https://lgbtqhealthcaredirectory.org
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Palefsky JM, et al. Treatment of anal high-grade squamous intraepithelial lesions to prevent anal cancer. New England Journal of Medicine, 2022;386:2273–2282. The ANCHOR trial. https://www.cancer.gov/news-events/press-releases/2022/hiv-hsil-anal-cancer-anchor-study
Stier EA, et al. International Anal Neoplasia Society's consensus guidelines for anal cancer screening. International Journal of Cancer, 2024. https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.34850
ASCCP Practice Advisory: Anal Cancer Screening. Reproduces the IANS thresholds in a clinician-facing format. https://www.asccp.org/Assets/6e8dcdcb-d093-42ef-97cd-70a8c30dbf3e/638641643094670000/asccp-practice-advisory-anal-cancer-screening-final-pdf
Panel on Opportunistic Infections in Adults and Adolescents with HIV. Human Papillomavirus Disease section. Updated July 2024, reviewed March 2026. https://clinicalinfo.hiv.gov/sites/default/files/guidelines/documents/adult-adolescent-oi/human-papillomavirus-adult-adolescent-oi.pdf
US Preventive Services Task Force. Anal Cancer: Screening. Topic inactive; no recommendation issued. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/anal-cancer-screening
Clifford GM, et al. A meta-analysis of anal cancer incidence by risk group. International Journal of Cancer, 2021;148:38–47.
"No Time for That: Health Care Economics and Population Health Limitations of Anal Cancer Screening." July 2025. Source for the HRA workforce figures. https://pmc.ncbi.nlm.nih.gov/articles/PMC12872286/
National Cancer Institute. Studies Aim to Advance Screening for Anal Cancer. Source for the self-collection trial data. https://www.cancer.gov/news-events/cancer-currents-blog/2024/anal-cancer-screening-self-collected