Treatment of high-grade anal intraepithelial neoplasia with infrared coagulation in a primary care population of HIV-infected men and women

BACKGROUND: High-grade anal intraepithelial neoplasia the putative anal carcinoma precursor, is more common in HIV-infected persons. The ideal treatment for these lesions has not been established. OBJECTIVE: The aim of this study was to evaluate the effectiveness of infrared coagulation treatment for highgrade anal intraepithelial neoplasia. DESIGN: This is a prospective cohort study. Patients with high-grade anal intraepithelial neoplasia either received infrared coagulation treatment or voluntarily did not receive treatment and were reevaluated at a subsequent time point. SETTING: This investigation was performed at a Ryan White-funded clinic located in the United States. PATIENTS: HIV-infected men and women with biopsy-confirmed high-grade anal intraepithelial neoplasia were included. MAIN OUTCOME MEASURES: The primary outcome measured was the histology collected by high-resolution anoscopy-directed biopsy. RESULTS: The study included 124 patients. Of 42 patients who either delayed treatment or were not treated, 37 (88%; 95% CI = 74%-96%) still had high-grade anal intraepithelial neoplasia on reevaluation and 2 (5%; 95% CI = 1%-16%) had squamous-cell carcinoma. Of 98 patients who received infrared coagulation treatment, 73 (74%; 95% CI = 65%-83%) patients had no evidence of high-grade anal intraepithelial neoplasia on their first posttreatment evaluation, and none had progressed to squamous-cell carcinoma (p < 0.0001 in comparison with untreated). Upon completing all initial and, if necessary, follow-up treatment, 85 (87%; 95% CI = 78%-93%) patients treated by infrared coagulation had no evidence of high-grade anal intraepithelial neoplasia and none had progressed to squamous-cell carcinoma. LIMITATIONS: The study population may not be representative of the general population, the study environment was uncontrolled, and patients were not randomly assigned to treatment. CONCLUSIONS: Infrared coagulation is an effective treatment for high-grade anal intraepithelial neoplasia.