New cell findings on low-grade squamous intraepithelial lesions (LSIL): minimizing the atypical squamous cells of undetermined significance (ASC-US) diagnosis rates

Objective : We studied cytological low-grade squamous intraepithelial lesions (LSIL) guidelines based on the detection of cells with a high-risk of human papillomavirus (HPV) infection in cases of atypical squamous cells of undetermined significance (ASC-US). Study Design : Study materials were liquid cervical cytological specimens from 151 cases diagnosed as ASC-US. We identified HPV infection using L1 polymerase chain reaction (L1-PCR) and identified HPV-infected cells using in situ PCR. Results : High-risk HPV was detected in 86.8% of ASC-US cases. Among 7 cell features indicative of HPV infection, binucleation (compression+) and nuclear enlargement (irregular chromatin distribution) had sensitivity exceeding 40% and specificity exceeding 90% in detecting high-risk HPV. High-risk HPV was detected by in situ PCR in 100% of cells showing binucleation (compression+) and in 81.9% of cells with nuclear enlargement (irregular chromatin distribution). The presence of cells with binucleation (compression+) and nuclear enlargement (irregular chromatin distribution) correlated significantly with high-risk HPV infection (p