"Equivocal" high-risk HPV DNA tests performed on ThinPrep specimens after ASC-US diagnoses are associated with an increased incidence of CIN3: a cytologic/histologic review of 315 cases.

ABSTRACT

OBJECTIVE: The Hybrid Capture II high-risk HPV test (HC II hrHPVT) improves early detection of cervical neoplasia in Pap tests. However, weakly positive HC II results may be reported as indeterminate or "equivocal," for which there is little clinical guidance. This study is designed to evaluate the clinical outcome of equivocal HC II hrHPVTs and concurrent atypical squamous cells of undetermined significance (ASC-US) on ThinPrep Pap specimens through correlation with 2-year follow-up cervical biopsies. MATERIALS AND METHODS: Over a 5-year period, ThinPrep Pap tests diagnosed as ASC-US were grouped according to their hrHPVT results (i.e., positive, negative, or equivocal) and correlated with histologic follow-up. All equivocal and representative positive and negative hrHPVTs were included. Biopsies showing high-grade dysplasia were reviewed by two pathologists. RESULTS: Of 9,012 ASCUS Pap tests, 945 had corresponding hrHPVTs and follow-up cervical biopsies. High-grade squamous intraepithelial lesion (HSIL-cervical intraepithelial neoplasia grades 2/3, CIN2/3) was identified in 20.3% (14/69) of biopsies after equivocal hrHPVTs (CIN2-5.8%, CIN3-14.5% (p=.0261); 16.7% (25/150) after positive hrHPVT (CIN2-12%, CIN3-4.7%); and 5.4% (5/93) of biopsies after negative hrHPVT (CIN2-4.3%, CIN3-1.1%). CONCLUSION: ASC-US in association with equivocal and positive HC II results respectively shows similar incidences of CIN2/3 on 2-year follow-up cervical biopsy. Additionally, a significant proportion of CIN3 biopsies are in the equivocal HC II cohort. As clinical decision making would be impacted by this finding, laboratories should consider evaluating the clinical performance of their HC II assay via correlation with subsequent cervical biopsies.