{"entity":{"id":"anchor","kind":"trial","name":"ANCHOR","aka":["ANCHOR study","Anal Cancer/HSIL Outcomes Research","AMC-A01"],"tldr":"ANCHOR proved for the first time that treating precancerous anal lesions in people with HIV prevents anal cancer: those whose lesions were removed or ablated were 57 percent less likely to develop cancer than those who were simply monitored, which is the evidence behind screening and treating these lesions.","summary":"ANCHOR was a phase 3 trial of the AIDS Malignancy Consortium that screened more than 10,000 people living with HIV and randomised 4,459 with biopsy-proven anal high-grade squamous intraepithelial lesions to treatment or active monitoring. Treatment was mostly office-based infrared coagulation, hyfrecation or laser ablation, with topical fluorouracil or imiquimod or surgical excision as alternatives; monitoring was high-resolution anoscopy every six months with biopsy of suspected cancer. The primary endpoint was time to progression to anal cancer.\n\nThe monitoring committee stopped the trial early for efficacy. At a median follow-up of 25.8 months, nine cancers were diagnosed in the treatment group (173 per 100,000 person-years) and 21 in the monitoring group (402 per 100,000 person-years), a 57 percent reduction. The result led the United States guidelines to recommend anal cancer screening and treatment of high-grade lesions in people with HIV, which is how the corpus's anal cancer precursor page cites it.","status":"positive","asOf":"2026-09-22","links":[{"label":"ClinicalTrials.gov NCT02135419","url":"https://clinicaltrials.gov/study/NCT02135419"}],"tags":["soc-trials"],"related":[],"cancers":["anal-hsil-precursor","anal"],"sections":[],"technologies":["active-surveillance"],"targets":[],"drugs":["fluorouracil","imiquimod"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-anchor-treatment-of-anal-hsil-prevents-cancer-palefsky-nejm-2022"],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT02135419","phase":"3","setting":"People living with HIV aged 35 or older with biopsy-proven anal high-grade squamous intraepithelial lesions at 25 US sites: treatment of the lesions (mainly office-based ablation, with topical fluorouracil or imiquimod or excision) against active monitoring every six months, with progression to anal cancer as the primary endpoint","sponsor":"AIDS Malignancy Consortium","result":"Progression to anal cancer 173 per 100,000 person-years with treatment against 402 with active monitoring, a 57 percent reduction (95% CI 6 to 80, p 0.03); the trial stopped early for efficacy.","yearReported":2022,"enrolled":4446,"enrolledBasis":"analysed","enrolledNote":"The registry counts 4,446 participants; 4,459 were randomised and 4,446 (99.7 percent) analysed for time to progression to cancer in the New England Journal of Medicine report.","outcomes":[{"endpoint":"Incidence of anal cancer","primary":true,"unit":"cases per 100,000 person-years","arms":[{"name":"Treatment of high-grade lesions","value":173,"note":"9 cases; 95% CI 90 to 332; median follow-up 25.8 months"},{"name":"Active monitoring","value":402,"note":"21 cases; 95% CI 262 to 616"}],"p":"0.03","source":"https://doi.org/10.1056/NEJMoa2201048"},{"endpoint":"Reduction in the rate of progression to anal cancer with treatment","unit":"%","arms":[{"name":"Treatment against active monitoring","value":57,"note":"95% CI 6 to 80"}],"source":"https://doi.org/10.1056/NEJMoa2201048"}]},"route":"/trials/anchor/","neighbours":{"cancer":[{"id":"anal","kind":"cancer","name":"Anal cancer (squamous cell carcinoma)","route":"/cancers/anal/"},{"id":"anal-hsil-precursor","kind":"cancer","name":"Anal high-grade squamous intraepithelial lesions (precursor)","route":"/cancers/anal-hsil-precursor/"}],"technology":[{"id":"active-surveillance","kind":"technology","name":"Active surveillance","route":"/technologies/active-surveillance/"}],"drug":[{"id":"fluorouracil","kind":"drug","name":"Fluorouracil (5-FU)","route":"/drugs/fluorouracil/"},{"id":"imiquimod","kind":"drug","name":"Imiquimod","route":"/drugs/imiquimod/"}],"paper":[{"id":"paper-anchor-treatment-of-anal-hsil-prevents-cancer-palefsky-nejm-2022","kind":"paper","name":"ANCHOR: treatment of anal high-grade squamous intraepithelial lesions to prevent anal cancer","route":"/key-papers/paper-anchor-treatment-of-anal-hsil-prevents-cancer-palefsky-nejm-2022/"}]}}