Introduction/Background In spite of the high probability of spontaneous regression of ASCUS and LSIL, persistent minor cervical abnormalities were occasionally observed in women with HPV infection. Until now, efficient predictive biomarker reflecting the prognosis of persistent ASCUS and LSIL was not developed. The aim of this study was to find the best predictive model for diagnosis of CIN2+ using immunocytochemical expression of HPV L1 capsid protein in patients with persistent ASCUS and LSIL with high risk of HPV infection.

Methodology A total of 285 cervical cytology samples (70 ASCUS and 215 LSIL Pap smear) were analyzed in this study. Immunocytochemical identification of HPV L1 capsid protein in cervical cytology samples was performed using the Cytoactive^® HPV L1 screening set. The expression rate of the HPV L1 capsid protein in cervical cytology was calculated, and correlation between HPV L1 expression in cytology and cervical pathologic diagnosis was evaluated. The risk for CIN2+ was calculated using results of immunocytochemistry and HPV DNA test.

Results Negative results for HPV L1 were more frequently observed in CIN2+, and positive expression of HPV L1 capsid protein was higher in CIN1 or cervicitis (Fisher’s exact test, p<0.05). Diagnosis rates for CIN2+ were the highest for the combination of HPV L1 capsid protein immunocytochemistry, cytology and HPV test when compared with other combinations (AIC: 191.7, SC: 206.3, p<0.001).

Conclusion Negative expression of HPV L1 capsid and HPV type 16 or 18 infection can predict progression to CIN2+ in women showing persistent ASCUS and LSIL. Therefore, HPV L1 immunocytochemistry and the HPV type test can be useful to predict diagnosis of CIN2+ in women with persistent ASCUS or LSIL.

Disclosure Nothing to disclose.