Comparing Diagnostic Efficacy of Pap Smear, Liquid-Based Cytology and HPV DNA in Cervical Cancer Screening

This study aimed to compare the efficacy of conventional Pap smears with liquid-based cytology (LBC) in screening for cervical cancer. It also studied the presence of HPV (human papillomavirus) infection, and its diagnostic accuracy to predict cervical carcinoma was also studied. The study was conducted in the Department of Obstetrics and Gynecology of a tertiary care teaching hospital in Mysore between December 2020 and February 2023. A total of 50 women presently with cervical abnormality were clinically examined, followed by cervical sample collection for Pap smear and LBC. The sample remaining from the LBC was subjected to HPV DNA testing. A biopsy specimen was taken for the study participants to confirm the diagnosis and calculate sensitivity, specificity, and overall diagnostic accuracy for all three screening tests. The mean age of patients was 42.82 ± 4.6 years, with 56% from rural areas and 78% belonging to socioeconomic classes IV and V. Sample adequacy of the LBC was 98%, while that of the Pap smear was only 82% (p<0.05). The concordance rate between LBC and Pap smear was found to be 84%. The sensitivity of LBC, Pap smear, and HPV DNA was 95.0%, 42.0%, and 89.4%, while the specificity was 100%, 100%, and 93.5%, respectively. The study found LBC to have greater efficacy than the Pap smear in terms of both sample adequacy and diagnostic accuracy. The smear findings of LBC and Pap smear had good concordance. HPV DNA testing had the lowest diagnostic accuracy when compared to the other two tests. Therefore, we conclude LBC to be a better screening test than Pap smear and HPV DNA for cervical cancer in the absence of economic constraint.