Atypical squamous cells of undetermined significance in liquid-based cytologic specimens: results of reflex human papillomavirus testing and histologic follow-up in routine practice with comparison of interpretive and probabilistic reporting methods.

Background: Human papillomavirus (HPV) DNA testing for high-risk types after Papanicolaou (Pap) smear interpretations of atypical squamous cells of undetermined significance (ASCUS) is a sensitive method for identifying women who harbor underlying high-grade squamous intraepithelial lesions (HSIL). To the authors' knowledge, the application of HPV testing to ASCUS smears in routine practice with comparison of probabilistic and interpretive models of cytologic reporting has not been reported.

Methods: HPV DNA testing was performed reflexively on 216 liquid-based Pap smears that initially were interpreted as ASCUS.