Adding HPV16 testing to abnormal cervical smear detection is useful for predicting CIN3: a prospective study

Background. The aim of this prospective study was to estimate whether adding human papillomavirus 16 (HPV16) testing to abnormal cervical smears is useful in the prediction of cervical intraepithelial neoplasia 3 (CIN3). Methods. Between October 1994 and May 1996, a total of 207 patients at the Akita University Hospital had abnormal smears. Of these patients, 153 patients with CIN1,2 or atypical squamous cells of undetermined significance (ASCUS) were enrolled in this study and followed until June 2001. At the initial visit, a cervical swab was collected for cytology and for HPV16 testing using nested polymerase chain reaction (PCR). When the HPV16 test was positive, HPV16 testing was performed every 3 to 6 months. We compared the prevalence of progression to CIN3 between the HPV16‐positive group (n = 16) and the HPV16‐negative group (n = 137). We also investigated the risk of progression to CIN3 associated with persistent HPV16 infection. Results. At the end of the study period, four patients (25%) in the HPV16‐positive group developed CIN3, and all of these patients were found to have persistent HPV16 infection during this period. Only three patients (2.2%) in the HPV16‐negative group developed CIN3. Conclusions. The prevalence of progression to CIN3 in the HPV16‐positive group was significantly higher than that in the negative group (p = 0.0023). The odds ratio of progression to CIN3 was 14.9 [95% confidence interval (CI) 2.98–74.4]. In particular, the risk of progression to CIN3 increased with persistent HPV16 infection. Adding HPV16 testing when abnormal cervical smears are detected promises to be useful for predicting CIN3.