New Research Shows Early Anal Lesion Treatment Reduces Cancer Risk

A large clinical trial study has found the active treatment of a type of high-risk anal lesion can reduce the development of anal cancer by more than half in people living with HIV (PLWH).

The results entitled “Design of the Anal Cancer/HSIL Outcomes Research study (ANCHOR study): A randomized study to prevent anal cancer among persons living with HIV” were published in the New England Journal of Medicine and suggest early and aggressive treatment of high grade squamous intraepithelial lesions (HSIL) can significantly reduce the incidence of anal cancer among people living with HIV. 

The study reported early treatment of anal HSIL “showed efficacy in reducing the incidence of anal cancer, a vital step towards having treatment of anal HSIL become the standard of care not only for PLWH but for all populations at increased risk of anal cancer.”

High grade squamous intraepithelial lesions (HSIL) are abnormal growths that appear on the surface of the skin around the anus. These growths are generally benign but considered cancerous when they progress downward into layers of tissue below the skin. Since the development of cancer from HSIL is rare in the general population, most doctors choose to simply monitor the condition rather than aggressively treat HSIL from its onset.

People living with HIV are five times more likely to develop cancer from HSIL, however, as high as 14.1 percent over a five-year progression among people living with HIV as opposed to 3.2 percent among those not living with HIV according to the study.

ANCHOR sought to determine if treatment of HSIL would lower the rate of the development of cancer versus simply monitoring the patient’s condition. The study limited eligibility to people who were living with HIV, were 35 years of age or older, were generally healthy and “able to perform normal activities” or were “ambulatory and able to carry out work of a light or sedentary nature” if symptomatic, had a life expectancy greater than five years, and who met certain other medical and treatment criteria. Younger participants were excluded from the study since they have a much lower incidence rate of cancer developing from HSIL and would have required a far larger sample size to more accurately assess.

Participants and their clinicians were given a list of approved treatments that sought to include at least one administered by the patient (such as topical creams) and at least one that required a doctor to administer (such as surgical excision).

The study observed a reduction of over 50 percent in the incidence of anal cancer in people living with HIV who were treated for anal HSIL versus those whose conditions were merely monitored. According to its authors, the study also shows the potential benefits of early treatment of HSIL for all people at risk of developing cancer, and not just people living with HIV.