DIAGNOSTIC ACCURACY OF CONVENTIONAL PAP SMEAR AND LIQUID-BASED CYTOLOGY FOR CERVICAL CANCER SCREENING

Abstract

Objective:

To determine the accuracy of conventional Pap smear and liquid-based cytology for cervical cancer screening taking histopathology as gold standard.

Methods:

This cross-sectional study involving 153 suspected patients of cervical cancer was conducted in the Department of Obstetrics & Gynaecology, DHQ Hospital, DG Khan, from July 2024 to January 2025. All participants underwent a series of diagnostic procedures, including Pap smear, colposcopy, and cervical biopsy. Considering biopsy as the gold standard, the sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of both Pap smear and LBC were evaluated.

Results:

The mean age was 39.5 years with a standard deviation of 7.5 years. Regarding parity, 15.0% (23 patients) were primiparous, while 85.0% (130 patients) were multiparous. In terms of menstrual status, 70.5% (108 patients) were premenopausal, and 29.5% (45 patients) were menopausal. The diagnostic accuracy of the PAP smear and liquid-based cytology (LBC) was assessed. The sensitivity of the PAP smear was 47.2%, while that of LBC was higher at 66.0%. The specificity was comparable between the two methods, with the PAP smear at 90.0% and LBC at 89.0%. The positive predictive value (PPV) was 71.4% for the PAP smear and 76.1% for LBC. Additionally, the negative predictive value (NPV) was 76.3% for the PAP smear and 83.2% for LBC.

Conclusion:

This comparative study shows that Liquid-Based Cytology (LBC) has significantly higher diagnostic accuracy than Pap smear in cervical cancer screening. These results support the potential use of LBC in routine screening programs, particularly in settings with adequate resources and infrastructure.