Significance of p16/Ki-67 double immunocytochemical staining in cervical cytology ASCUS, LSIL, and ASC-H

Abstract

Objective: To investigate the application value of p16/cell proliferation associated nuclear antigen (Ki-67) double-staining and human papillomavirus mRNA in the cytological screening. Methods: Two hundred and fifty-one cases who suffered from atypical squamous cell of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), atypical squamous cell-cannot exclude high-grade squamous intraepithelial lesion (ASC-H) in ThinPrep cytologic test (TCT) were collected in Peking University First Hospital between October 2015 and March 2016. And p16/Ki-67 double-staining and hybrid capture Ⅱ (HC-Ⅱ) detection were performed on the cervical cells. The result was compared with the pathological result of colposcope guided biopsy. All statistical analysis was completed by Stata 12.0 statistical software analysis. The results of diagnostic tests were described by using the sensitivity, specificity, positive predictive value,negative predictive value, and the area under the receiver operating characteristic (ROC) curve. Results: (1) One hundred and eight cases of liquid based cytology diagnosis of ASCUS patients, the positive rate of p16/Ki-67 was 13.9% (15/108), 102 cases of liquid based cytology diagnosis of LSIL patients, the positive rate of p16/Ki-67 was 21.6% (22/102), 41 cases of liquid based cytology diagnosis of ASC-H patients, the positive rate of p16/Ki-67 was 39.0% (16/41), compared amongthree groups, the difference was statistically significant (χ(2)=78.516, P<0.05); cervical exfoliated cells p16/Ki-67 expression rate was 13.0%(28/215) in cervical low-grade lesions [cervical intraepithelial neoplasia (CIN) Ⅰ], which was 69.4%(25/36) in high level lesions (CIN Ⅱ-Ⅲ), the difference was statistically significant (χ(2)=7.932, P<0.05). (2) The specificity of p16/Ki-67 detection and diagnosis were higher than those of HC-Ⅱ in ASCUS, LSIL, and ASC-H (89.8% vs 71.4%, 83.3% vs 15.6%, 88.9% vs 40.7%; all P<0.05), meanwhile, the positive predictive value of p16/Ki-67 detection and diagnosis exceed those of HC-Ⅱ in ASCUS, LSIL, and ASC-H (33.3% vs 26.3%, 31.8% vs 12.6%, 81.3% vs 38.5%; all P<0.05). Moreover, the ROC curve of p16/Ki-67 were bigger than those of HC-Ⅱ in ASCUS, LSIL, and ASC-H (0.799 vs 0.696, 0.708 vs 0.531, 0.909 vs 0.561; all P<0.05). Conclusion: For patients with cytological diagnosis of ASCUS, LSIL, and ASC-H, p16/Ki-67 double staining method could be used as an effective method to assist in the diagnosis of high-grade cervical lesions, and the screening efficiency is superior to that of high-rist HPV.