How Reliable Is the Pap Smear in Detecting Cervical Epithelial Abnormalities in Modern Practice: A Critical Evaluation

Background: Cervical cancer is still a major health problem causing mortality of women worldwide, particularly in developing countries.Pap smear has played a pivotal role in screening cervical cancer till date.Aim: The objective of the study is to evaluate whether cervical Pap smear study is still relevant and can effectively diagnose precancerous and cancer of the cervix without the assistance of molecular diagnostics.Materials and methods: An observational, prospective, cross-sectional, institutional-based study was conducted in two tertiary care hospitals in eastern region of India, over a period of 3 years.The study population included sexually active women attending gynecology outdoors with variable complaints related to the cervix like white discharge, bleeding, pain in the abdomen, etc.A total of 742 Pap smears were studied after the Papanicolaou staining by automated stainer and reported as per the latest Bethesda system for reporting cervical cytology.Cytologically diagnosed epithelial abnormalities were sent for biopsy.Hematoxylin and eosin (H&E) sections were studied for histological diagnosis and analyzed for cytohistological comparison in cases with epithelial cell abnormalities.Results: The maximum cases were in the age-group 41-50 (280, 37.7%) of which the majority were negative for intraepithelial lesion or malignancy (NILM) (92%).With increasing age, the epithelial abnormalities were predominant: 60% in 71 years and above, 28% in 61 to 70 years, and 19% in 51 to 60 years.Symptomatically postmenopausal bleeding was associated with epithelial abnormalities (24/50 cases, 48%), whereas white discharge was associated with NILM (108/110 cases, 98%).Cytologically diagnosed were low-grade squamous intraepithelial lesion (LSIL) (6.2%), high-grade intraepithelial lesion (HSIL) (2.4%), atypical squamous cell of undetermined significance (ASCUS) (3.1%), and squamous cell carcinoma (SCC) (0.8%).Overall cytohistological concordance was 86.3% in the present study, with sensitivity (96%), specificity (82%), positive predictive value (PPV) (97%), negative predictive value (NPV) (78%), and diagnostic accuracy (94%).All cytological and histopathological categories were found to be statistically significant by t-test. Conclusion:The diagnostic efficacy of the Pap smear is high.Being quick and cheap, a Pap smear still holds its usefulness as a first-point screening test for cervical lesions despite newer diagnostic modalities.