Liquid-based cytology versus conventional cytology in women with squamous intraepithelial lesions of the uterine cervix

Abstract

Objective: The aim of the study was to compare the results of two cervical cytology techniques, liquid-based and conventional, using the cervical biopsy as the gold standard for diagnosis of squamous intraepithelial lesion (SIL) of the uterine cervix. Material and Methods: This comparative prospective study was conducted in a series of 200 sexually active patients, aged from 19 to 49, who came to their annual gynecological exam at University Clinic of Gynecology and Obstetrics in Skopje between January and October 2015. In all patients, simultaneously, conventional Papanicolaou smear and Thin Prep liquid-based samples were taken. The performance of both techniques was compared with the gold standard of the biopsy results in a series of 118 patients with squamous cell abnormalities of the uterine cervix. In all these patients a colposcopically directed biopsy with endocervical curettage was taken. Results: When comparing the cytological diagnoses the agreement between two cytology methods for all 200 cases was 76%. The diagnostic efficiency between the two methods was further evaluated by comparing the cytological diagnosis of each method with the histopathological diagnosis in the series of 118 patients. Histology confirmed a presence of a low-grade squamous intraepithelial lesion in 54 and a high-grade squamous intraepithelial lesion in 6 cases, while the remaining 58 cases had negative diagnostic interpretation. The liquid-based cytology was in agreement with histology in 81% of the biopsies in comparison to the conventional cytology which was in agreement with histology in 61% of the biopsies. Conclusions: In conclusion, the results of our study suggest that the liquid-based cytology is a more sensitive (80%) and specific (83%) technique than the conventional cytology (sensitivity=57%, specificity=65%) in comparison to histology as a gold standard.