The expression of p16 (INK4a) and Ki‐67 in relation to high‐risk human papilloma viral load and residual disease after conization with positive margins

The purpose of this study was to investigate the correlations between high-risk human papillomavirus (HPV) load and p16 (INK4a) or Ki-67, and to identify biomarkers that may predict residual disease after conization with positive margins. The following samples were analyzed: 49 paraffin-embedded specimens from patients with cervical intraepithelial neoplasia (CIN), including 12 CIN 2 conization specimens and 37 CIN 3 conization specimens. Immunohistochemical analysis was performed with antibodies to p16 (INK4a) and Ki-67. Hybrid Capture II testing was used to detect high-risk HPV DNA. The mean HPV loads within each of the p16 (INK4a)-staining cases were 9.5 (relative light units/positive control) RLU/PC for negative staining, 531.8 RLU/PC for 1+ staining, 140.2 RLU/PC for 2+ staining, and 545.1 RLU/PC for 3+ staining. HPV loads differed significantly according to p16 (INK4a) expression (P = 0.0021). The mean HPV loads within Ki-67 staining cases were 28.2 RLU/PC for 1+ staining, 189.6 RLU/PC for 2+ staining, and 563.3 RLU/PC for 3+ staining. HPV loads differed significantly according to Ki-67 expression (P = 0.0259). The expression of p16 (INK4a) (P = 0.0012) and Ki-67 (P = 0.0006) were significantly associated with the CIN grade. In univariate and multiple logistic regression analysis, age, parity, cytology, lesion grade in the cone, high-risk HPV load, and the expression of p16 (INK4a) and Ki-67 were not significantly associated with residual lesions after conization with positive margins (P > 0.05). In conclusion, high-risk HPV load showed significant differences according to the expression of p16 (INK4a) and Ki-67, while none of the prognostic factors were significantly associated with residual disease after conization with positive margins.