Atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion triage in Korean women: Revisiting the 2012 American Society of Colposcopy and Cervical Pathology screening guidelines

OBJECTIVE To determine whether triage for atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) from the updated American Society for Colposcopy and Cervical Pathology cervical cancer screening guidelines is applicable in Korean women. METHODS We investigated women with ASC-US or LSIL including referred from local hospitals visited for cervical cancer screening at Korea University Guro Hospital from February 2004 to December 2014. Detailed information on the results of Papanicolaou (Pap) smears, human papillomavirus (HPV) DNA tests, and cervical biopsies were collected through chart review. Cervical biopsy results were compared in eligible women according to individual Pap smear findings and HPV DNA status. RESULTS Of 216,723 possible cases, 3,196 were included. There were 212 (6.6%) women with ASC-US and 500 (15.6%) with LSIL. The risk of ≥cervical intraepithelial neoplasia (CIN) 2 was significantly higher in women who were ASC-US/HPV+ than ASC-US/HPV- and LSIL/HPV+ than LSIL/HPV- (93.3% vs. 6.7% and 96.7% vs. 3.3%, P<0.001 and P<0.001, respectively). The risk of ≥CIN 3 was also significantly higher in women who were ASC-US/HPV+ than ASC-US/HPV- and LSIL/HPV+ than LSIL/HPV- (97.0% vs. 3.0% and 93.0% vs. 7.0%, P<0.001 and P<0.001, respectively). Age-stratified analysis revealed that more CIN 2 or CIN 3 was diagnosed in women aged 30 to 70 with ASC-US or LSIL when HPV DNA was present. CONCLUSION Observation with Pap and HPV DNA tests rather than immediate colposcopy is a reasonable strategy for ASC-US or LSIL when the HPV DNA test is negative, especially in women aged 30 to 70. Reflection of these results should be considered in future Korean screening guidelines.