Liquid-Based cytology in the detection of premalignant lesions in patients with "atypia in squamous cells" in conventional cytology

Background: The management of patients with "Atypical Squamous Cells " (ASC) in conventional papanicolaou smears (CPS) is based on the risk of high-grade squamous intraepithelial lesion (HSIL). The efficacy of liquid-based cytology (LBC) to detect this premalignant lesion is variable, with little evidence of its performance in Colombian patients. Aims: The aim of this study is to determine the performance of LBC in the detection of premalignant lesions, in patients with ASC in CPS. Materials and Methods: Were obtained patients who attended colposcopy clinic due the result of ASC in CPS. An LBC was taken, which was interpreted by two pathologists without access to other results. The performance of LBC to detect HSIL, was determined, considering as a gold standard: histopathological study/negative-satisfactory colposcopy. Results: Were included 114 patients, with a mean age of 38.4 years (SD +/- 13.3). LBC had abnormal results in 40.36% (n = 46), with a slightly higher proportion of low-grade squamous intraepithelial lesion (LSIL) than HSIL. The total of abnormal diagnoses by colposcopy and/or biopsy was 51.75% (n = 59), with a predominance of LSIL (36.84%). The sensitivity of the liquid-based cytology to detect premalignant lesions was 76.5%, specificity: 66.0%, positive predictive value: 28.3% and negative predictive value: 94.1%; The Cohen's kappa index of LBC for detecting HSIL was 0.2492 for the total population and 0.2907 for >= 30 years. Discussion: Although LBC decreases abnormal cytology and increases the detection of HSIL, which improves diagnostic accuracy; sensitivity and predictive values for detecting HSIL are not significantly different between CPS and LBC.