Morphological correlation of human papillomavirus infection of matched cervical smears and biopsies from patients with persistent mild cervical cytological abnormalities

Abstract

Human papillomavirus (HPV) analysis of cytological material has been advocated for determining those patients with low-grade cervical cytological abnormalities who have current high-grade squamous intraepithelial lesions (SILs). In this study, we analyzed concurrent cervical smears and biopsies from 167 patients with Papanicolaou (Pap) smears showing persistent atypical squamous cells of uncertain significance (ASCUS) or low grade SILs (1) to compare the detection of HPV by nonisotopic in situ hybridization (NISH) on matched smears and biopsies; (2) to analyze the type and distribution of NISH signal within lesions; and (3) to define further the ability of NISH techniques to distinguish between patients with low- and high-grade SIL. Whether present in cervical smears or biopsies, high-risk HPV types (16, 18, 31, 33, and related types) were significantly associated with high-grade SILs ( P < .001) but were found in 15% of low-grade SILs. Ninety percent of high grade lesions were directly infected by these HPV types, and good concordance (92.2%) was found between NISH analysis of matched cervical smears and biopsies, indicating accurate colposcopic targetting of biopsies and excision specimens. Punctate signal morphology, which correlates with viral integration, was associated with high-grade SILs but was also observed in two low-grade SILs. Although the presence of high-risk HPV types in low-grade SILs limits the predictive ability of HPV testing by this means in this group of patients, those patients with high-risk HPV infection of low-grade SILs may be at greater risk of progression to high-grade SIL or invasive carcinoma. If this were the case, HPV testing would be of potential value in the management of patients with low-grade cytological abnormalities.