Incidence of High Grade Squamous Intraepithelial Lesions in Patients with Atypical Squamous Cells of Undetermined Significance Papanicolaou Smears at Naresuan University Hospital

Purpose: To determine the incidence of high-grade cervical intraepithelial neoplasia (CIN2-3) among patients with atypical squamous cells of undetermined significance (ASC-US) Papanicolaou (Pap) smears. Materials and Methods: One-hundred and eighty-seven patients with ASC-US Pap smears who underwent colposcopy with histological study were enrolled between September 2007 and August 2015. Patient factors (including age, parity, current pills used, HIV status, age at first sexual intercourse and number of sexual partners) were obtained. Logistic regression analysis was used to evaluate clinical factors associated with CIN2-3. Results: CIN was diagnosed in 92 of 187 women (49.2%). Sixty-one of these (32.6%) had CIN1 and 31 (16.6%) had CIN2-3. There was no woman who had invasive cancer. There was no correlation of high-grade CIN with factors in this study including age, parity, current pills used, HIV status, age at first sexual intercourse and number of sexual partners. Conclusions: Data from this study showed no invasive cervical cancer was found in patients with ASC-US. There was no patient factor associated with high grade intraepithelial neoplasia in patients with ASC-US Pap smears.