High-risk human papillomavirus infection among women with atypical squamous cells of undetermined significance in Pap smear: A seven-year follow-up study in South India.

Abstract

Background: Well-defined pre-cancerous stages help early detection of uterine cervical cancer by Pap smear or human papillomavirus (HPV) analysis. HPV induces atypical squamous cells of undetermined significance (ASCUS) which can progress to higher grade lesions depending on persistence of infection with High-risk human papillomavirus (HrHPV). The HrHPV prevalence and persistence after 18-36 months, associated risk factors for persistence among women with ASCUS, and the effect of persisting HrHPV in the cytological progression upto a period of seven years are analyzed.

Methods: In the routine Pap smear clinic of a Women and Children Hospital, women who had ASCUS in Pap smear in 2009-2011 were the sample for the study. A sample of 152 women with ASCUS in Pap smear, were subjected for HrHPV (16, 18, 31, 33 and 42) analysis. These women were invited for a repeat Pap smear and HrHPV analysis after 18 months. Women with HrHPV in both the rounds were advised to come for yearly routine follow-up Pap smear upto seven years.

Results: The HrHPV prevalence was 46%, HrHPV persistence within 18-36 months was 60.8% and clearance was 39%. Among many risk factors for HrHPV persistence in univariate analysis, having more than two pregnancies and unhealthy appearing cervix were significant in multivariate analysis. 94% of the women with persistent ASCUS or higher lesion within seven years were initially persistent HrHPV positives.

Conclusion: Since persistence of HrHPV in the cervix at least for 2 years helps in the persistence or progression of ASCUS even after seven years, routine HPV analysis should be done for women with ASCUS cytology, and who have high parity and unhealthy cervix. These women should be closely followed up to identify the progression to higher grade lesions.