P16/Ki-67 Immunostaining in the Triage of Postmenopausal Women With Low-Grade Cytology Results.

Abstract

The interpretation of postmenopausal smears and the gynecological treatment of these patients can often be difficult. The objective of this study was to assess the performance of p16/Ki-67 dual-stained cytology as a triage of atypical squamous cells of undetermined significance and low-grade intraepithelial lesion cytology results in postmenopausal women. All consecutive atypical squamous cells of undetermined significance and low-grade intraepithelial lesion smears in 1-year period were collected and p16/Ki-67 immunostaining was performed retrospectively. The results were compared with histology results or long-term cytology follow-up in cases with no biopsy. The sensitivity of p16/Ki-67 immunostaining for the detection of cervical intraepithelial neoplasia (CIN) 2 and CIN 3 was 57.1% and 85.0%, respectively. The specificity for the detection of CIN 2 was 94.3% and CIN 3 92.4%. Negative predictive values for the detection of CIN 2 and CIN 3 were 96.3% and 99.6%, respectively. Dual p16/Ki-67 immunostaining is a useful additional method in postmenopausal patients with low-grade cytology. Considering the high specificity and negative predictive value in our study, we believe that it could be helpful in avoiding unnecessary referrals to colposcopy and thus reduce the cost of the program.