The Predictive Value of p16 INK4a and Hybrid Capture 2 Human Papillomavirus Testing for High-Grade Cervical Intraepithelial Neoplasia

Abstract

We performed p16(INK4a) immunocytochemical analysis and Hybrid Capture 2 (HC2; Digene, Gaithersburg, MD) high-risk HPV testing on 210 abnormal SurePath (TriPath Imaging, Burlington, NC) Papanicolaou specimens diagnosed as low-grade squamous intraepithelial lesion (LSIL) or high grade squamous intraepithelial lesion (HSIL). The results were compared with 121 follow-up biopsy specimens. p16(INK4a) was positive in 57.9% of women with LSIL compared with 97.1% of women with HSIL. In contrast, HC2 testing was positive in 85.0% of women with LSIL and 86.4% of women with HSIL. The differences in the positive rates for16(INK4a) between LSIL and HSIL was significant (P < .001), whereas, for HC2, it was not (P = .264). In patients who had cervical biopsies following a cytologic diagnosis of LSIL, the positive predictive value (PPV) of p16(INK4a) for a biopsy of cervical intraepithelial neoplasia grade 2 or 3 (CIN2/3; 33.3%) was significantly higher than the PPV of HC2 results (21.2%) (P < .001). Using liquid-based cytology specimens, p16(INK4a) immunocytochemical analysis has a higher PPV than reflex HC2 HPV testing for identifying CIN2/3 among patients with LSIL and might be useful for selecting patients with LSIL for colposcopy.