Is the Low-Grade Squamous Intraepithelial Lesion/Atypical Squamous Cells Cannot Exclude High-Grade Squamous Intraepithelial Lesion Category Associated with Cervical Intraepithelial Neoplasia 2?

Objective: A number of cervical smears may exhibit unequivocal low-grade squamous intraepithelial lesions (LSIL) in association with atypical cells cytomorphologically suspicious, but not sufficient to be interpreted as high-grade squamous intraepithelial lesions (HSIL). These lesions are presently called LSIL, atypical squamous cells cannot exclude HSIL (LSIL/ASC-H). Previous studies have shown that LSIL/ASC-H and ASC-H are both equivocal for HSIL and have a high risk of underlying HSIL. However, in researching the literature only two studies were found which rendered the results as cervical intraepithelial neoplasia (CIN) 2 and CIN3 separately. The purpose of this study was to compare the distribution of biopsy results for CIN2 and CIN3 in patients with ASC-H, HSIL, and LSIL/ASC-H. Study Design: Between January 2005 and December 2011, cervicovaginal smears (98,594) with a diagnosis of ASC-H, LSIL, LSIL/ASC-H, or HSIL were re-evaluated to determine the prevalence of future lesion development. Results: A total of 252 patients who had histologic follow-up within a year were selected. Among these, LSIL/ASC-H (31.7%) had the highest prevalence of CIN2 between LSIL (9.3%), ASC-H (10%), and HSIL (16%). All differences were statistically significant. Conclusion: Because of the high predictive value of CIN2, LSIL/ASC-H may have further importance, especially in women of different age groups.