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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] »