[Analysis of the efficacy and safety of laser therapy for high-grade anal intraepithelial neoplasia in HIV-negative women].

Objective: To evaluate the efficacy and safety of laser therapy in human immunodeficiency virus (HIV)-negative women with high-grade anal intraepithelial neoplasia (HGAIN). Methods: This study was a retrospective clinical study. HIV-negative patients who were first diagnosed with HGAIN in Obstetrics and Gynecology Hospital of Fudan University from January 2021 to June 2025 were included. All patients received CO₂ laser therapy at intervals of 4-6 weeks, for a maximum of four sessions. Treatment response was assessed 4-6 weeks after the final session via high-resolution anoscopy (HRA). Patients who achieved complete remission (CR) began follow-up at 6 months post-treatment, with subsequent surveillance including cytology, human papillomavirus (HPV) testing, HRA, and biopsy (if indicated) every 6-12 months to monitor recurrence. Results: A total of 64 patients were included, with a median age of 47.5 years (range: 25.0-68.0 years). Comorbid immune system diseases were found in 38% (24/64) of patients, HPV 16/18 infection rate was 70% (45/64), and 70% (45/64) had a lesion area≤50%. Eleven patients were lost to follow-up, and 53 patients were finally included in the efficacy analysis. The CR rate of laser therapy was 85% (45/53). Compared with the CR group, patients with persistent lesions were older (median age: 37.0 vs 52.5 years, P=0.028) and had a higher proportion of lesions>50% [22% (10/45) vs 5/8, P=0.033]. Among 45 patients with CR, the median follow-up was 11 months (range: 6-46 months), the recurrence rate was 40% (18/45), and the 1-year recurrence-free survival rate was 67.7%. Comorbid immune system disease was an independent risk factor for recurrence (HR=6.513, 95%CI: 1.866-22.735, P=0.003). The incidence of treatment-related adverse events was 64% (34/53), all of which were mild, mainly anal pain or discomfort (40%, 21/53) and mild bleeding (32%, 17/53), with no severe complications. Conclusions: CO₂ laser therapy is an effective and well-tolerated treatment for HGAIN in HIV-negative women, yielding a high CR rate and a favorable safety profile. Comorbid immune system disease is an independent risk factor for post-treatment recurrence, highlighting the need for enhanced follow-up and individualized management in these patients.