Background. The cytological interpretation of ASC-US represents a category of morphologic uncertainty. For patients with this result, other tests are necessary in order to determine the risk for cervical lesions.

Materials and methods. 198 patients with ASC-US cytology have been analyzed between 2008 and 2013. All the patients included in the study have subsequently had a high oncogenic HPV testing and colposcopy risk. 103 (52%) patients tested positive for high risk HPV and 21 (10%) had associated colposcopy changes and precancerous and cancerous lesions identified through biopsy. 95 (48%) patients tested negative for HPV and none of these women had lesions at colposcopy.

Results and discussion. High oncogenic risk HPV testing was proven useful in identifying the patients with ASC-US cytology who are at high risk for cervical lesions (100% sensibility). In this study, the HPV testing had a negative predictive value of 100%, which uselessly renders a further colposcopy evaluation. HPV testing for women with ASC-US is not specific in identifying women with cervical lesions (Specificity 53%) and this results from a high prevalence of limited HPV infections in an age group which is less than 30 years old.

Conclusions: High risk HPV testing for women with ASC-US cervical cytology is useful in determining the risk for precancerous and cancerous cervical lesions. A positive result is associated with a high risk for cervical lesions (20%) and for these patients colposcopy is necessary. For women with a negative result, the risk for cervical lesions is practically null so colposcopy is not required.

Abbreviations: HPV = Human Papilloma Virus, ASC-US = Atypical Squamous Cells of Undetermined Significance, CIN = Cervical Intraepithelial Neoplasia, DNA = Deoxyribonucleic Acid, Pap = Papanicolaou test, LSIL = Low Grade Squamous Intraepithelial Lesion, HSIL = High Grade Intraepithelial Lesion.