Clearance of human papillomavirus infection after successful conization in patients with cervical intraepithelial neoplasia

The natural history of high-risk human papillomavirus (HRHPV) infection after successful treatment of cervical intraepithelial neoplasia (CIN) is not well known. This study was performed to evaluate the rate and pattern of HRHPV infection clearance after successful conization for CIN and to analyze factors associated with such clearance. A total of 287 patients who underwent loop electrosurgical excision procedures (LEEP) owing to HRHPV-associated CIN were included. All patients had negative resection margins on LEEP specimens and underwent HPV testing with the hybrid capture II system at 3-, 6-, 9-, 12-, 18 and 24-month follow-up visits after LEEP. Persistent HPV infections were detected in 45.6%, 14.3%, 6.3%, 2.2%, 1.5% and 1.1% of patients at 3, 6, 9, 12, 18 and 24 months after LEEP, respectively. Clearance rates did not differ by age, parity or severity of cervical lesion. However, clearance rates were significantly slower in patients with HPV DNA loads >500 RLU/PC before LEEP (p = 0.040). During 2 years of follow-up after LEEP, 24 patients had recurrent disease revealed by biopsy. The odds ratios for recurrent disease in patients with persistent HRHPV infection increased gradually from 5.17 at the 3-month follow-up visit to 12.54, 15.69 and 25.90 at 6-, 9-, 12- and 24-month follow-up visits, respectively. We conclude that HRHPV infection cleared gradually in most patients within 6 months of treatment. Clearance rates were significantly slower in patients with HPV DNA loads >500 RLU/PC. Persistent HPV infection was a significant positive predictor of recurrence.