A team of researchers, including LSU Health New Orleans Infectious Diseases and Microbiology professor Michael Hagensee, MD, PhD, has shown for the first time that treating precancerous anal growths called high-grade squamous intraepithelial lesions (HSILs) in persons living with HIV significantly decreased the progression to anal cancer. Results are published in the New England Journal of Medicine.

Like cervical cancer, anal cancer is caused by human papillomavirus (HPV), leading to precancerous high-grade squamous intraepithelial lesions that can progress to cancer.

"Treatment of high-grade cervical lesions is known to prevent cervical cancer in women," notes Dr. Hagensee. "Anal cancer has Increased 25-fold in persons living with HIV, and the ANCHOR study is based on the same approach."

The ANCHOR (Anal Cancer-HSIL Outcomes Research) trial enrolled more than 4,000 people living with HIV who had high-grade anal lesions on biopsy at 25 sites in the US.

"We screened over 300 people at University Medical Center and followed 100 with high-grade lesions," says Dr. Hagensee, who sees patients at UMC, a major LSU Health New Orleans teaching hospital.

Participants were randomly assigned to a treatment group or a group who were closely observed, the current standard of care. Those in the treatment group underwent procedures to remove the lesions -- office-based ablative procedures, ablation or excision under anesthesia -- or the administration of topical fluorouracil or imiquimod. Treatment reduced anal cancer by 57%.

Although anal cancer is rare in the general population, with 9,440 new cases estimated in 2022, the incidence has been increasing in the US. The highest risk is for persons living with HIV.

"Our results support the use of screening and treatment for anal HSIL as the standard of care for persons living with HIV," Dr. Hagensee concludes. "Next steps include determining the best way to screen persons living with HIV for detecting high-grade lesions, when should this screening start and at what intervals, and what is the best way to treat someone with high-grade anal lesions."

The research was supported by the National Cancer Institute of the National Institutes of Health.