Genotype-specific human papillomavirus detection in cervical smears

Human papillomavirus (HPV) is widely accepted as a causative agent of cervical cancer. The distribution and prevalence of HPV types depend on geographic region and demographic factors. The aim of this study was to investigate the relationship between the presence of various HPV types and the outcome of cytological examination. Cervical smears were obtained from 125 women from southern Poland: low grade squamous intraepithelial lesions (LSIL) - 44, high grade squamous intraepithelial lesions (HSIL) - 12, cervical carcinoma - 27 and 42 women without abnormality in cytology as a control group. DNA was extracted from the smears and broad-spectrum HPV DNA amplification and genotyping was performed with the SPF 10 primer set and reverse hybridisation line probe assay (INNO-LiPA HPV Genotyping, Innogenetics). HPV DNA was detected in approximately 72% cases, more frequently in women with squamous intraepithelial lesions and cervical carcinoma than in the control group (P < 0.0005). The most frequent type found was HPV 16 (37%), followed by HPV 51 (28%) and HPV 52 (17%). A single HPV type was detected in 51% positive cases, more frequently in cervical cancer specimens. Multiple HPV infection was dominant in women with LSIL and normal cytology. Prevalence of HPV 16 increased with the severity of cervical smear abnormality. For women HPV 16 positive, the relative risk (odds ratio) of the occurrence of HSIL and cervical cancer versus LSIL was 14.4 (95% CI, 3.0-69.2; P=0.001) and 49.4 (95% CI, 6.5-372.8; P < 0.001), respectively. Genotyping of HPV will allow better classification of women with cervical abnormalities into different risk groups and could be useful in therapy.