Background: To compare the cytomorphological features of atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H) observed in a liquid-based Pap smear with the histopathological features observed in a concurrent colposcopic biopsy specimen obtained immediately after obtaining the Pap smear. Methods: Cytomorphological features such as cytoplasmic differentiation, nuclear/cytoplasm (N/C) ratio, chromatin pattern, thickening of nuclear contour, and the appearance of the nucleolus of 247 ASC-H obtained from 25 liquid-based Pap smear ASC-H cases were compared with those of the cells obtained from biopsied samples. Human papillomavirus (HPV) infection was tested for 39 HPV genotypes using Uniplex E6/E7 polymerase chain reaction method. Results: Of the 25 ASC-H cases, 22 (88%) showed cervical intraepithelial neoplasia grade 1 or greater (CIN1+) and 3 (12%) were benign. HPV infection was detected in 100% CIN1+ cases and 66.7% benign cases. Significant differences such as marked hyperchromasia, thickened nuclear contour, and prominent nucleoli were observed between ASC-H cases with CIN1+ and the benign cases. Conclusion: The presence of small dysplastic cells displaying marked hyperchromasia, thickening of nuclear contour, and prominent nucleoli on Pap smear strongly suggest the presence of CIN in ASC-H cases.
Keywords: ASC-H; CIN; HPV; cytomorphological features.