Abstract
Objective: To compare the evaluation results and diagnostic performance of liquid based cytology (LBC) with those of conventional smears in cervical cancer screening.
Subjects and Methods: Smears were taken from women who visited our clinic for an examination by SurePath LBC or the conventional method according to the timing of the appointment. The number of samples taken was 1,796 for LBC and 1.835 for the conventional method. Evaluations were made according to Bethesda System 2001 and additional tests were conducted using the Hybrid Capture 2 assay for high risk types of human papillomavirus (HPV) when the evaluation was atypical squamous cells of undetermined significance (ASC-US) for both types of smear. Those who were positive in the HPV test were referred for colposcopy and histopathologic diagnoses.
Results: The percentage of unsatisfactory slides was significantly lower with LBC (2.07% vs. 0%, p<0.0001). The percentage of normal slides (NILM) did not differ between the 2 types of sample. The detection rate of ASC-US was significantly higher for LBC (0.72 % vs. 2.45%, p<0.0001), though the rates for other categories (ASC-H, LSIL, HSIL, AGC) did not differ. HPV testing was conducted for 8 (61.5%) conventional smears and 19 (43.2%) LBC smears. One (12.5%) conventional smear and 4 (21.1 %) LBC smears were positive. Upon referral for colposcopy, 3 smears were diagnosed as moderate dysplasia and 1 as mild dysplasia.
Conclusions: LBC reduced the proportion of unsatisfactory slides and had a higher detection rate for the ASC-US category, in which dysplastic lesions are included, when compared with conventional smears. Combined with additional testing for high-risk HPV types, LBC could improve diagnostic performance in cervical cancer screening.
