Difference in prevalence of human papillomavirus genotypes in cytomorphologically normal cervical smears is associated with a history of cervical intraepithelial neoplasia.

Abstract

The prevalence of human papillomavirus (HPV) genotypes was investigated by the polymerase chain reaction (PCR) method in cytologically normal and abnormal cervical scrapes obtained from asymptomatic women (n = 1,346), participating in a triennial screening program for cervical cancer, and from a gynecological outpatient population (n = 593). In the symptom-free population oncogenic HPV types 16, 18, 31 and 33 were present in 1.5% of cytologically normal scrapes, while the overall HPV prevalence rate was 3.5%. Significantly, higher HPV prevalence rates of 7% (oncogenic HPV; p less than 0.01) and 14% (all HPV; p less than 0.01), respectively, were found in cytologically normal scrapes of the gynecologic outpatient population. It appeared that in this outpatient group 78% of the smears containing HPV 16 and 18 were associated with a history of cervical pathology, i.e. cervical intraepithelial neoplasia grade I to III. In smears with mild and severe dysplasia and smears suspected of carcinoma in situ from both populations, the overall HPV prevalence was 70%, 84% and 100%, respectively. In all squamous-cell carcinomas of the cervix (n = 50) HPV was detected. Frequencies of HPV 16 and 18 increased from 41% in mild dysplasia to 94% in cervical carcinomas. Since a low prevalence of HPV was found in cytomorphologically normal cervices of women without a clinicopathological history, the findings in this study suggest that HPV detection in population-based screening programs for cervical neoplasia can be an important tool in identifying women who are at risk of developing dysplasia and cervical cancer.