High-Risk Human Papillomavirus (hrHPV) E6/E7 mRNA Testing by PreTect HPV-Proofer for Detection of Cervical High-Grade Intraepithelial Neoplasia and Cancer among hrHPV DNA-Positive Women with Normal Cytology

Abstract

T o reduce the mortality and morbidity of cervical cancer, most developed countries have adopted some form of cervical screening using cytological examination of cervical smears. However, cervical cytology is known to display only a modest sensitivity for cervical precancer or cancer (i.e., cervical intraepithelial neoplasia grade 2 or higher [ՆCIN2]) (3, 15).Infection with high-risk human papillomavirus (hrHPV) has been recognized as the necessary cause of cervical cancer (27,44). Recently, evidence has accumulated that a considerable improvement of the effectiveness of cervical cancer screening can be achieved by using hrHPV DNA testing as a primary screening tool. hrHPV DNA testing has a higher sensitivity for ՆCIN2 and consequently better protects against high-grade CIN and cervical cancer in the subsequent screening round than cytology (2,8,21,29,33,35). This permits extension of the screening interval. Nonetheless, hrHPV infections are rather common in a screened population and most are transient. In fact, the positive predictive value (PPV) of an hrHPV test for ՆCIN2 is rather low (i.e., only a small proportion of the women who test positive for hrHPV DNA will have or develop ՆCIN2 lesions). It is therefore important to consider alternative or supplementary testing methods in order to limit unnecessary follow-up procedures for women with clinically irrelevant, transient hrHPV infections.In this context, reflex cytology has been advocated as a valuable triage tool for hrHPV DNA-positive women. In population-based screening programs, hrHPV-positive women with abnormal cytology have a high risk of underlying ՆCIN2, but this does not account for the up to 8% of the hrHPV-positive women with normal cytology who also have or will develop ՆCIN2 (16, 34). Thus, there is a need for biomarkers that allow stratification of hrHPV-positive women with normal cytology for risk of ՆCIN2 or, alternatively, for biomarkers that can replace cytology as a triage tool. As activity of the hrHPV oncogenes E6 and E7 is pivotal not only for the initiation but also for maintenance of the malignant phenotype (48), demonstration of hrHPV E6/E7 transcripts might be more specific than hrHPV DNA testing for detection of ՆCIN2. Transcript analysis is nowadays feasible on cervical scrapings because the introduction of liquid-based cytology has resulted in collection media that preserve RNA sufficiently to allow in vitro amplification and detection (13). The PreTect HPVProofer assay (NorChip AS, Klokkarstua, Norway) has been de-

Effectiveness of a two‐stage strategy with HPV testing followed by visual inspection with acetic acid for cervical cancer screening in a low‐income setting

“…[46][47][48] In conclusion, adding VIA to HPV testing improves PPV of cervical cancer screening, but at the cost of an important loss of sensitivity. Further studies are warranted to explore this strategy.…”

Expression of human papillomavirus E6 and E7 oncoprotein mRNA in women with low-grade squamous intraepithelial lesions or less

“…The molecular detection of HPV provides evidence of the infection and Rijkaart et al (2012) demonstrated the risk of cervical intraepithelial neoplasia grade 2 or higher (≥CIN2) in 55% of women with positive expression of E6/E7 mRNA, HPV DNA with high positive oncogenic risk and normal oncotic cytologies, compared with 20% in those with negative test results. The authors concluded that the test could aid in the selection of women with high-oncogenic risk HPV for prompt referral or a colposcopic examination.…”

CerviCal Cytology, HPv DNa aND mrNa – a ComParative StuDy iN 162 PatieNtS

“…It has to be considered that despite normal cytology, women positive for high-risk HPV genotypes have much higher risk of developing CIN3+ in the future (33) . It has been recently shown among cytologically normal women, those testing E6/E7 mRNA positive were at a much higher risk for CIN2+ development comparing to mRNA negative, on a short follow-up period within 3 years (34) . NILM subjects harboring HPV 16 DNA may represent, in a subset, limitations of the cytological diagnosis.…”