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« Historically, HPV testing [15] was introduced to compensate for the poor sensitivity and specificity of the Pap smear cytology often used as a diagnostic tool for borderline precancerous lesions. The only FDA approved Digene Hybrid Capture 2 (HC2) assay is commonly used to determine if a cervicovaginal lavage sample harbors »high-risk« HPVs [16], as an adjunctive test for evaluation of the cytologically borderline cases [17-19]. However, it is now recognized that persistent infection of a »high-risk« HPV, not the HPV virus itself, is the pivotal promoter incausing cervical precancerous lesions and cancer [7-10].
Most of HPV infections, even caused by »high-risk« genotypes, are transient with normal Pap cytology in sexually active young women [1, 3-6]. In 93% of the initially infected women, the same viral type is not detected upon re-examination four menstrual cycles later [20]. The median duration of positivity detectable by PCR for a specific HPV type in these young women is 168 days [21]. Multiple »high-risk« HPV infections do not constitute a higher risk for the development of cervical neoplasia when compared with single high-risk HPV infection [22]. For the development and maintenance of a high-grade squamous intra epithelial lesion (SIL), the risk is greatest in women positive for the same genotype of HPV on repeated testing [7-9]. Viral load is not a useful parameter to predict high-grade SIL [23]. High-grade SIL is often associated with a viral DNA load lower than that observed in less severely affected cells [24] »