A groundbreaking national trial has shown that anal cancer can be prevented by routine screening and removal of precancerous cells.

What is the ANCHOR Study?

The ANCHOR Study hoped to improve patient outcomes for people with anal precancer and cancer by finding the best way to stop anal precancer from progressing to cancer.

ANCHOR stands for Anal Cancer HSIL Outcomes Research and the study investigated treating anal cancer precursor lesions to see if this reduced the cancer risk for people living with HIV.

ANCHOR aimed to recruit 5,000 people living with HIV and was randomized into two groups: treatment of anal precancer and a control group. The incidence of anal cancer is highest in people living with HIV.

Who conducted ANCHOR?

ANCHOR occurred in 21 locations around the United States. It was conceived and led by Anal Cancer Foundation Scientific Advisory Board Member Dr. Joel Palefsky.

What was ANCHOR researching?

Prevention and early detection are essential to ending anal cancer. Yet, despite its growing incidence and mortality, there are no national screening guidelines for anal cancer or precancer. The rates of cervical cancer reduced by 80% once doctors starting screening for and treating cervical precancer.

The hope was that the ANCHOR study would illustrate treating anal precancer will reduce the risk of anal cancer. The Anchor study had two main objectives: to determine the effectiveness of screening for and treating anal precancer to reduce the incidence of anal cancer in HIV-positive men and women, and to create a bank of blood, anal swab, and tissue specimens to support critical scientific studies on how anal cancer progresses. There were two arms in the study: one arm that received treatment for anal precancer and a control arm that did not.

Ninety percent of anal cancer is caused by the human papillomavirus (HPV), which can cause changes to the skin around and inside the anus. These changes are called "high-grade squamous intraepithelial lesions" or HSIL. About half of HIV+ men who have sex with men have anal HSIL. Not all anal HSIL will develop into cancer. Most HSIL will go away on their own, but some become cancer over time and can eventually spread to other parts of the body.

What were the outcomes?

For now, we know that NIH halted the study due to the therapy’s success in reducing the incidence of anal cancer. Researchers will compile the data and submit for publication after peer review. It is expected that the data will provide guidance on recommendations to make anal cancer prevention programs the standard of care for people at high risk of anal cancer.

What role did ACF play?

The Anal Cancer Foundation built and led the coalition of organizations that supported and pushed for the study. As part of its advocacy, ACF submitted testimony on behalf of the organizations in 2011 and 2012. Note, at the time it was called the HOST study.

What does this mean for the anal cancer community?

Anal cancer is currently rapidly increasing at 3% a year. More people are being diagnosed with late stage anal cancer than ever before.

We need standard methods to find it early. The study proved that treating anal precancer in people living with HIV, the group at most high-risk for developing anal cancer, reduces their cancer risk. The next step is ensuring this becomes standard of care so that we can end anal cancer by finding it and treating it before it ever becomes cancer.

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