Silent High Grade Cervical Intraepithelial Neoplasia Diagnosis of Atypical Smear between Conventional and Liquid Based Papanicolaou Smear in Suburban Area of Thailand

Objectives: To evaluate the prevalence of silent high grade cervical intraepithelial neoplasia diagnose in atypical squamous cells of undetermined significance (ASC-US) in cytology result between conventional (CPP) and liquid-based cervical cytology (LBP) methods to suggest the proper management for Thai women.Methods: This retrospective study was conducted at Bhumibol Adulyadej Hospital, Bangkok, Thailand between January 2011 and December 2016. Medical records of 28,564 patients who attended for cervical cancer screening were reviewed. Prevalence of silent high grade cervical intraepithelial neoplasia (CIN) in atypical squamous cells of undetermined significance (ASC-US) cytology result was determinedResults: During the study period, 28,564 cases were enrolled. There were 22,552 and 6,012 of CPP and LBP cases, respectively. A total of 644 cases of ASC-US cytology were enrolled. In women with ASC-US in cytology, the mean age was younger than women with negative screening cytology group and approximately 70% were in pre-menopausal status. Prevalence of high grade cervical intraepithelial neoplasia in ASC-US cytology from CPP and LBP were 9.5 and 11.9%, respectively. Ten percent (23/248) of atypical glandular cytology pattern was cancer. One-quarter of them was endometrial cancer.Conclusion: Silent high grade cervical intraepithelial neoplasia in ASC-US cytology and the rate of cancer in atypical glandular cytology pattern were high. We recommended colposcopy for women who had the cervical cytological report as atypical squamous and glandular cytology pattern.