Comparing triage algorithms using HPV DNA genotyping,HPV E7 mRNA detection and cytology in high-risk HPV DNA-positive women

BackgroundHigh-risk human papillomavirus (hrHPV) DNA positive women require triage testing to identify those with high-grade cervical intraepithelial neoplasia or cancer (≥CIN2).ObjectiveComparing three triage algorithms (1) E7 mRNA testing following HPV16/18/31/33/45/52/58 genotyping (E7 mRNA test), (2) HPV16/18 DNA genotyping and (3) cytology, for ≥CIN2 detection in hrHPV DNA-positive women.Study designhrHPV DNA-positive women aged 18–63 years visiting gynecology outpatient clinics were included in a prospective observational cohort study. From these women a cervical scrape and colposcopy-directed biopsies were obtained. Cervical scrapes were evaluated by cytology, HPV DNA genotyping by bead-based multiplex genotyping of GP5+6+-PCR-products, and presence of HPV16/18/31/33/45/52/58 E7 mRNA using nucleic acid sequence-based amplification (NASBA) in DNA positive women for respective HPV types. Sensitivities and specificities for ≥CIN2 were compared between E7 mRNA test and HPV16/18 DNA genotyping in the total group (n = 348), and E7 mRNA test and cytology in a subgroup of women referred for non-cervix-related gynecological complaints (n = 133).ResultsSensitivity for ≥CIN2 of the E7 mRNA test was slightly higher than that of HPV16/18 DNA genotyping (66.9% versus 60.9%; ratio 1.10, 95% CI: 1.0002–1.21), at similar specificity (54.8% versus 52.3%; ratio 1.05, 95% CI: 0.93–1.18). Neither sensitivity nor specificity of the E7 mRNA test differed significantly from that of cytology (sensitivity: 68.8% versus 75.0%; ratio 0.92, 95% CI: 0.72–1.17; specificity: 59.4% versus 65.3%; ratio 0.91, 95% CI: 0.75–1.10).ConclusionFor detection of ≥CIN2 in hrHPV DNA-positive women, an algorithm including E7 mRNA testing following HPV16/18/31/33/45/52/58 DNA genotyping performs similar to HPV16/18 DNA genotyping or cytology.     

Comparison of HPV detection technologies: Hybrid capture 2, PreTect HPV-Proofer and analysis of HPV DNA viral load in HPV16, HPV18 and HPV33 E6/E7 mRNA positive specimens

Human papillomavirus (HPV) testing using molecular methods in liquid based cytology (LBC) specimens may be useful as an adjunct to cervical screening by cytology. We compared the positivity rate of the commercially available HPV DNA method hybrid capture 2 (hc2) and the commercially available E6/E7 mRNA method PreTect HPV-Proofer in cytological specimens (n=299). LBC specimens collected (n=299) represented the following cervical cytological disease categories: Normal (n=60), borderline nuclear abnormalities (BNA) (n=34), CIN1 (n=121), CIN2 (n=60), CIN3 (n=24). Overall, 69% (205/299) of the cases were positive by hc2 and 38% (112/299) of the cases were positive by PreTect HPV-Proofer. Concordance rates between the two tests were highest in the high-grade cytology cases (CIN2: 67% and CIN3: 83%) and the normal cytology cases (88%) and lowest in the BNA and CIN1 categories (56% and 52%). HPV DNA viral load analyses were carried out on HPV16 (n=55), HPV18 (n=9) and HPV33 (n=13) samples that were positive by PreTect HPV-Proofer. The sensitivity and specificity of PreTect HPV-Proofer and the hc2 DNA test for the detection of high-grade cytology (i.e. CIN2+) were 71.4% and 75.8% vs 100% and 43.7%, respectively. The relatively low detection rate observed by PreTect HPV-Proofer in the whole range of cytological positive cases, combined with a relatively higher specificity and PPV, suggests that PreTect HPV-Proofer may be more useful than hc2 for triage and in predicting high-grade disease.     

Sensitivity, specificity, and clinical value of human papillomavirus (HPV) E6/E7 mRNA assay as a triage test for cervical cytology and HPV DNA test

There is evidence that testing for human papillomavirus (HPV) E6/E7 mRNA is more specific than testing for HPV DNA. A retrospective study was carried out to evaluate the performance of the PreTect HPV-Proofer E6/E7 mRNA assay (Norchip) as a triage test for cytology and HPV DNA testing. This study analyzed 1,201 women, 688 of whom had a colposcopy follow-up and 195 of whom had histology-confirmed high-grade intraepithelial neoplasia or worse (CIN2+). The proportion of positive results and the sensitivity and specificity for CIN2+ were determined for HPV mRNA in comparison to HPV DNA and cytology. All data were adjusted for follow-up completeness. Stratified by cytological grades, the HPV mRNA sensitivity was 83% (95% confidence interval [CI] = 63 to 94%) in ASC-US (atypical squamous cells of undetermined significance), 62% (95% CI = 47 to 75%) in L-SIL (low-grade squamous intraepithelial lesion), and 67% (95% CI = 57 to 76%) in H-SIL (high-grade squamous intraepithelial lesion). The corresponding figures were 99, 91, and 96%, respectively, for HPV DNA. The specificities were 82, 76, and 45%, respectively, for HPV mRNA and 29, 13, and 4%, respectively, for HPV DNA. Used as a triage test for ASC-US and L-SIL, mRNA reduced colposcopies by 79% (95% CI = 74 to 83%) and 69% (95% CI = 65 to 74%), respectively, while HPV DNA reduced colposcopies by 38% (95% CI = 32 to 44%) and by 15% (95% CI = 12 to 19%), respectively. As a HPV DNA positivity triage test, mRNA reduced colposcopies by 63% (95% CI = 60 to 66%), having 68% sensitivity (95% CI = 61 to 75%), whereas cytology at the ASC-US+ threshold reduced colposcopies by 23% (95% CI = 20 to 26%), showing 92% sensitivity (95% CI = 87 to 95%). In conclusion, PreTect HPV-Proofer mRNA can serve as a better triage test than HPV DNA to reduce colposcopy referral in both ASC-US and L-SIL. It is also more efficient than cytology for the triage of HPV DNA-positive women. Nevertheless, its low sensitivity demands a strict follow-up of HPV DNA positive-mRNA negative cases.     

Comparison of seven tests for high-grade cervical intraepithelial neoplasia in women with abnormal smears: the Predictors 2 study

High-risk human papillomavirus (HPV) DNA/RNA testing provides higher sensitivity but lower specificity than cytology for the identification of high-grade cervical intraepithelial neoplasia (CIN). Several new HPV tests are now available for this purpose, and a direct comparison of their properties is needed. Seven tests were evaluated with samples in liquid PreservCyt transport medium from 1,099 women referred for colposcopy: the Hybrid Capture 2 (Qiagen), Cobas (Roche), PreTect HPV-Proofer (NorChip), Aptima HPV (Gen-Probe), and Abbott RealTime assays, the BD HPV test, and CINtec p16(INK4a) cytology (mtm laboratories) immunocytochemistry. Sensitivity, specificity, and positive predictive value (PPV) were based on the worst histology found on either the biopsy or the treatment specimen after central review. Three hundred fifty-nine women (32.7%) had CIN grade 2+ (CIN2+), with 224 (20.4%) having CIN3+. For detection of CIN2+, Hybrid Capture 2 had 96.3% sensitivity, 19.5% specificity, and 37.4% PPV. Cobas had 95.2% sensitivity, 24.0% specificity, and 37.6% PPV. The BD HPV test had 95.0% sensitivity, 24.2% specificity, and 37.8% PPV. Abbott RealTime had 93.3% sensitivity, 27.3% specificity, and 38.2% PPV. Aptima had 95.3% sensitivity, 28.8% specificity, and 39.3% PPV. PreTect HPV-Proofer had 74.1% sensitivity, 70.8% specificity, and 55.4% PPV. CINtec p16(INK4a) cytology had 85.7% sensitivity, 54.7% specificity, and 49.1% PPV. Cytology of a specimen taken at colposcopy (mild dyskaryosis or worse) had 88.9% sensitivity, 58.1% specificity, and 50.7% PPV. Our study confirms that, in a referral setting, HPV testing by a number of different tests provides high sensitivity for high-grade disease. Further work is needed to confirm these findings in a routine screening setting.     

Cytology and human papillomavirus testing 6 to 12 months after ASCUS or LSIL cytology in organized screening to predict high-grade cervical neoplasia between screening rounds

We carried out a prospective study comparing the performance of human papillomavirus (HPV) E6/E7 mRNA (PreTect HPV-Proofer; NorChip, Klokkarstua, Norway) and DNA (Amplicor HPV test; Roche Diagnostics, Basel, Switzerland) triage testing of women 6 to 12 months after atypical-squamous-cells-of-undetermined-significance (ASCUS) or low-grade-squamous-intraepithelial-lesion (LSIL) cytology in organized screening to predict high-grade cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) between screening rounds. Between January 2005 and April 2008, 692 study women with screening-detected ASCUS/LSIL cytology 6 to 12 months earlier returned for HPV mRNA and DNA testing and repeat cytology. The median follow-up time was 3 years, using existing health care facilities. Follow-up test results were available for 625 women. Of the 145 CIN2+ cases detected during the study period, 95 (65.5%) were HPV mRNA positive 6 to 12 months after screening-detected ASCUS/LSIL, 44 (30.4%) were HPV mRNA negative, and 6 (4.1%) were invalid. The corresponding HPV DNA results were 139 (95.9%), 5 (3.4%), and 1 (0.7%), respectively. The cumulative incidences of CIN2+ 3 years after a negative HPV mRNA and DNA test were 10.3% (95% confidence interval [CI], 7.2 to 13.3%) and 1.8% (95% CI, 0.0 to 3.6%), respectively. The cumulative incidences of CIN2+ 3 years after positive HPV mRNA and DNA tests were 52.8% (95% CI, 40.1 to 60.1%) and 41.3% (95% CI, 35.5 to 46.6%), respectively. In conclusion, both positive HPV mRNA and DNA test results have a high enough long-term prediction of CIN2+ risk to consider referral to colposcopy as good practice when performed in delayed triage of women with ASCUS/LSIL cytology. In addition, the low CIN2+ risk among women with a negative Amplicor HPV test in our study confirms its safe use in a clinical setting.     

High concordance of results of testing for human papillomavirus in cervicovaginal samples collected by two methods, with comparison of a novel self-sampling device to a conventional endocervical brush

A user-friendly self-sampling method for collecting representative cervical cell material would lower the threshold for women to respond to the invitation for cervical screening. In the present article, we introduce such a device; we have evaluated its sensitivity and specificity to detect high-grade cervical intraepithelial neoplasia (CIN), via high-risk human papillomavirus (hrHPV) detection and liquid-based cytology (LBC), compared to endocervical brush samples obtained by gynecologists. Women who had a cervical smear reading of moderate dyskaryosis or worse or a repeat equivocal Pap smear result in the cervical screening program (n=64) and healthy volunteers (n=32) took a self-obtained sample at home prior to their visit to the gynecological outpatient department. At the outpatient department, an endocervical brush smear was taken, followed by colposcopy and biopsy whenever applicable. Both self-obtained samples and endocervical brush samples were immediately collected in Surepath preservation solution and used for LBC and hrHPV testing (by general primer-mediated GP5+/6+PCR). hrHPV test results showed a good concordance between the two sample types (87%; kappa=0.71), with sensitivities for prevalent high-grade CIN that did not differ significantly (92% and 95%; P=1.0). The hrHPV test on self-obtained samples proved to be at least as sensitive for high-grade CIN as cytology on endocervical brush samples (34/37 versus 31/37; P=0.5). LBC showed a poor concordance between self-obtained and endocervical brush samples (60%; kappa=0.27). In conclusion, self-obtained samples taken by this novel device are highly representative of the hrHPV status of the cervix. In combination with hrHPV testing, the use of this device may have implications for increasing the attendance rate for cervical screening programs.     

Aptima HPV E6/E7 mRNA test is as sensitive as Hybrid Capture 2 Assay but more specific at detecting cervical precancer and cancer

Detection of human papillomavirus (HPV) E6/E7 oncogene expression may be more predictive of cervical cancer risk than testing for HPV DNA. The Aptima HPV test (Gen-Probe) detects E6/E7 mRNA of 14 oncogenic types. Its clinical performance was compared with that of the Hybrid Capture 2 DNA test (HC2; Qiagen) in women referred for colposcopy and those routinely screened. Aptima was also compared with the PreTect HPV-Proofer E6/E7 mRNA assay (Proofer; Norchip) in the referral population. Cervical specimens collected in PreservCyt (Hologic Inc.) were processed for HPV detection and genotyping with the Linear Array (LA) method (Roche Molecular Diagnostics, Laval, Quebec, Canada). Histology-confirmed high-grade cervical intraepithelial neoplasia (CIN 2) or worse (CIN 2+) served as the disease endpoint. On the basis of 1,418 referral cases (CIN 2+, n = 401), the sensitivity of Aptima was 96.3% (95% confidence interval [CI], 94.4, 98.2), whereas it was 94.3% (95% CI, 92.0, 96.6) for HC2. The specificities were 43.2% (95% CI, 40.2, 46.2) and 38.7% (95% CI, 35.7, 41.7), respectively (P < 0.05). In 1,373 women undergoing routine screening (CIN 2+, n = 7), both Aptima and HC2 showed 100% sensitivity, and the specificities were 88.3% (95% CI, 86.6, 90.0) and 85.3% (95% CI, 83.5, 87.3), respectively (P < 0.05); for women ≥ 30 years of age (n = 845), the specificities were 93.9% (95% CI, 92.3, 95.5) and 92.1% (95% CI, 90.3, 93.9), respectively (P < 0.05). On the basis of 818 referral cases (CIN 2+, n = 235), the sensitivity of Aptima was 94.9% (95% CI, 92.1, 97.7) and that of Proofer was 79.1% (95% CI, 73.9, 84.3), and the specificities were 45.8% (95% CI, 41.8, 49.8) and 75.1% (95% CI, 71.6, 78.6), respectively (P < 0.05). Both Aptima and Proofer showed a higher degree of agreement with LA genotyping than HC2. In conclusion, the Aptima test is as sensitive as HC2 but more specific for detecting CIN 2+ and can serve as a reliable test for both primary cervical cancer screening and the triage of borderline cytological abnormalities.     

Isolation of RNA from residual BD SurePath liquid-based cytology specimens and detection of HPV E6/E7 mRNA using the PreTectt HPV-Proofer assay

Infection with high-risk human papillomavirus (HPV) is known to be associated directly with the development of cervical cancer. Recent data suggests that the detection of E6/E7 mRNA from high-risk HPV types may serve as a better diagnostic method for detecting the presence of cervical pre-cancer than HPV DNA testing. This report details a commercially available nucleic acid isolation protocol which can be used to isolate reproducibly RNA from residual BD SurePath liquid-based cytology specimens stored for up to 28 days, and have demonstrated the quality and quantity of mRNA is sufficient for detection with the NorChip PreTect HPV-Proofer assay. Of the 242 specimens tested in this study, 236 (97.5%) tested positive for U1A internal control gene expression. HPV type 16, 18, 31, 33 or 45 mRNA was detected in 16/20 (80%) of the analyzed high-grade squamous intraepithelial lesion (HSIL) specimens, with a low frequency of HPV mRNA detected in the normal lesions (3%). The presence of HPV E6 expression in a subset of HPV positive specimens was also detected by real-time RT-PCR. These findings confirm that RNA of sufficient quality can be isolated from residual BD SurePath cervical cytology specimens for use in downstream NASBA and RT-PCR-based assays.     

Intracellular Human Papillomavirus E6, E7 mRNA Quantification Predicts CIN 2+ in Cervical Biopsies Better Than Papanicolaou Screening for Women Regardless of Age

Context.-Cervical cancer screening in women younger than 30?years relies on cervical cytology because of the poor performance of human papillomavirus (HPV) DNA testing in this age group. Objectives.-To determine the performance of in-cell HPV E6, E7 mRNA quantification (HPV OncoTect) for the detection of high-grade cervical intraepithelial neoplasia in women younger than 30?years. Design.-We analyzed 3133 cytology specimens from a screening population of women aged 19-75?years investigate HPV OncoTect as a triage/secondary screening test for atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) cytology in women younger than 30?years. Test results were compared to histology in 246 cases. Results.-The sensitivity of E6, E7 mRNA was 89% for CIN 2+ and 100% for CIN 3+ lesions in women 30?years and older. In women younger than 30?years, the sensitivity of E6, E7 mRNA for CIN 2+ lesions was 88% for CIN 2+ and 92% for CIN 3+ lesions. Abnormal cytology (≥ASCUS) exhibited a sensitivity of 89% for CIN 2+ and 100% for CIN 3+ in women 30?years and older and 96% sensitivity for CIN 2+ and 93% sensitivity for CIN 3+ in women younger than 30. The specificity of E6, E7 mRNA was >80% for CIN 2+ and CIN 3+ in both groups of women compared to a specificity of abnormal cytology of <10% for CIN 2+ and CIN 3+ in both groups. Conclusions.-HPV OncoTect demonstrates a performance that would be effective for ASCUS/LSIL triage in women including those younger than 30?years.     

High-risk HPV testing in women with borderline and mild dyskaryosis: long-term follow-up data and clinical relevance.

In The Netherlands and most other European countries, women with two serial cervical smears with borderline or mild dyskaryosis (BMD) within 6 months are referred for colposcopy-directed biopsies. Only about 10% of these women have high-grade cervical intraepithelial neoplasia (CIN). This study therefore investigated whether human papillomavirus (HPV) testing could identify which women with smears read as BMD are most likely to have high-grade CIN, either at referral or during follow-up and the relationship was determined between clearance of high-risk HPV and regression of abnormal cytology. Women with smears read as BMD (n=278) were referred to the gynaecologist for colposcopy. They were subdivided into two groups; group A comprised women with a single smear (n=172) and group B women with two sequential smears (n=106) read as BMD before referral. High-risk HPV detection with Hybrid Capture II (HC II) was performed on a cervical scrape taken at the first visit before colposcopy (i.e. baseline smear) and during follow-up. Biopsies were taken when lesions suspected for CIN were seen at colposcopy. High-risk HPV DNA was present in the baseline smears of 126 (45.0%) women; 26 (20.6%) of them had histologically confirmed CIN 2/3 at the first visit and another 14 (11.1%) during follow-up. Only one of the 152 women (0.7%) with a negative high-risk HPV test had a CIN 2 lesion at the first visit and no CIN lesions were detected during follow-up of these women. After exclusion of women who were treated for prevalent high-grade CIN, the median follow-up times were 1.3 years (range 0.0-4.3 years) and 1.6 years (range 0.0-4.5 years) for women with HPV-negative and HPV-positive baseline smears, respectively. The sensitivity of a positive high-risk HPV test for CIN 2/3 at the first visit was 96.3%, the specificity 60.2%, the positive predictive value 20.6%, and the negative predictive value 99.3%. These values did not change markedly when stratified for group A or group B. Thus, a high-risk HPV positive test was strongly associated with the presence at the first visit and the development of CIN 2/3 lesions during follow-up. Moreover, regression of abnormal cytology in women with a positive high-risk HPV test at baseline was strongly associated with viral clearance and occurred 0.3 years (range -1.2 to 1.7 years) later than HPV clearance. This study establishes the value of a high-risk HPV positive test for women at risk of high-grade CIN, with virtually no risk for missing CIN 2/3. Addition of a test on high-risk HPV in women with BMD could prevent 55% of the referrals and/or repeat smears.     

Feasibility study of a human papillomavirus E6 oncoprotein test for diagnosis of cervical precancer and cancer

In a feasibility study using a prototype, lateral-flow test for human papillomavirus type 16, 18, and/or 45 (HPV16/18/45) E6 oncoproteins, 51 of 75 (68%; 95% confidence interval [95% CI] of 56 to 78%) of HPV16/18/45 DNA-positive specimens from women with a diagnosis of CIN3+ (cervical intraepithelial neoplasia grade 3+ or cervical cancer) tested positive for HPV16/18/45 E6 oncoprotein. None of 16 (95% CI of 0 to 37%) HPV16/18/45 DNA-positive cervical specimens from women with a negative or CIN1 diagnosis tested positive for HPV16/18/45 E6 oncoprotein.     

Prevalence and distribution of cervical human papillomavirus genotypes in women with cytological results from Sichuan province,China

The epidemiologic characteristics of human papillomavirus (HPV) genotypes vary by age, ethnicity, and geographic location, and the available data on HPV epidemiological characteristics with cytology results in Sichuan province are limited. Our research was conducted from June 2016 to July 2017. A total of 10 953 women getting HPV testing were enrolled. Liquid-based cytological and histological results were collected. The overall HPV infection rate was 24.1% in Sichuan province. The prevalence of high-risk HPV (hrHPV) was 19.9%. For hrHPV genotypes, HPV52 (15.5%) was the most prevalent genotype, followed by HPV16 (13.8%), HPV58 (13.3%), HPV51 (8.6%), HPV39 (8.1%), and HPV68 (7.8%). Among all HPV-positive women with a cytology or histology result, HPV16-positive women have the highest cervical intraepithelial neoplasia 1 (CIN1)+ prevalence (11.1%), followed by HPV18 and HPV33; HPV16-positive women also have the highest CIN2+ prevalence (9.3%), followed by HPV58 and HPV18. To date, this is the largest study done in the Sichuan province for HPV prevalence and subtype distribution with normal and abnormal cytological results. The age-specific prevalence in patients at gynecology clinics and other clinics is different. Besides, patients at the same age also have a different hrHPV prevalence and lrHPV prevalence. Our result revealed that in every 10 HPV16-positive women, there is approximately one women with CIN2, CIN3, or cervical cancer. A higher oncogenic potential of HPV58 than that of HPV52 was observed.     

HPV detection methods

Given the causal relation between a persistent high-risk human papillomavirus (hrHPV) infection and the development of high-grade cervical intraepithelial neoplasia (CIN) and cervical cancer, hrHPV testing has been advocated in addition to cytology for the detection of clinically relevant cervical lesions. HrHPV testing is thought to improve cervical screening algorithms, the management of women with cytologically equivocal smears, and the management of women treated for high grade CIN. In this chapter we discuss different methods for HPV detection and genotyping and their respective applications.     

Cross-sectional comparison of an automated hybrid capture 2 assay and the consensus GP5+/6+ PCR method in a population-based cervical screening program

In this cross-sectional study, clinical performances of the hybrid capture 2 assay using an automated instrument (i.e., rapid capture system) (hc2-RCS) and the high-risk human papillomavirus GP5+/6+ PCR-enzyme immunoassay (EIA) test were compared using cervical scrape specimens from 8,132 women that participated in a population-based screening trial. The hc2-RCS test scored significantly more samples positive (6.8%) than the GP5+/6+ PCR-EIA (4.8%) (P < 0.0005). This could be attributed largely to a higher positivity rate by the hc2-RCS test for women with cytologically normal, borderline, or mild dyskaryosis. A receiver operator characteristics analysis of the semiquantitative hc2-RCS results in relation to different cytology categories revealed that these differences are owing to differences in assay thresholds. For women classified as having moderate dyskaryosis or worse who also had underlying histologically confirmed cervical intraepithelial neoplasia grade 3 or cervical cancer (> or =CIN3), the hc2-RCS scored 97% (31/32) of samples positive, versus 91% (29/32) by GP5+/6+ PCR-EIA. However, this difference was not significant (P = 0.25). After increasing the hc2-RCS cutoff from 1.0 to 2.0 relative light units/cutoff value of the HPV16 calibrator (RLU/CO), no additional CIN3 lesions were missed by hc2-RCS, but the number of test-positive women with normal, borderline, or mild dyskaryosis was significantly decreased (P < 0.0005). However, at this RLU/CO, the difference in test positivity between hc2-RCS and the GP5+/6+ PCR-EIA was still significant (P = 0.02). The use of an RLU/CO value of 3.0 revealed no significant difference between hc2-RCS and GP5+/6+ PCR-EIA results, and equal numbers of smears classified as > or =CIN3 (i.e., 29/32) were detected by both methods. In summary, both assays perform very well for the detection of >or =CIN3 in a population-based cervical screening setting. However, adjustment of the hc2-RCS threshold to an RLU/CO value of 2.0 or 3.0 seems to produce an improved balance between the clinical sensitivity and specificity for > or =CIN3 in population-based cervical screening.     

Resolution of equivocal results with the Hybrid Capture II high-risk HPV DNA test: a cytologic/histologic review of 191 cases.

INTRODUCTION: The Hybrid Capture II (HC II, Digene) high-risk human papilloma virus (HPV) (hrHPV) DNA test is an in vitro nucleic acid hybridization assay that uses enhanced chemiluminescence for the qualitative and semiquantitative detection of hrHPV in cervical samples. Patient samples are concomitantly tested with positive and negative DNA controls and results reported as positive or negative on the basis of a ratio of relative light units to a cutoff value derived from the positive control (RLU/CO). Samples with a ratio <1.0 RLU/CO are expressed as negative for hrHPV, samples with a ratio >2.5 RLU/CO are expressed as positive for hrHPV, and samples with a ratio between these numbers are submitted for retesting. These "equivocal" values are resulted as positive for hrHPV if either of 2 subsequent test values equals or exceeds 1.0 RLU/CO. Samples that show <1.0 RLU/CO after 2 repeat tests are resulted as negative for hrHPV. METHODS: In this study, we evaluated all hrHPV test results over a 17-month period in our institution. Initial tests showing an equivocal result were analyzed for final retesting result, and for all corresponding and subsequent cytology and histology results. All hrHPV tests were conducted on SurePath (TriPath) or ThinPrep (Cytyc) cervical cytology specimens using the HC II hrHPV DNA test. Subsequent hrHPV tests also were correlated with incident and follow-up findings. RESULTS: A total of 4792 hrHPV test results were evaluated. Of these, 191 (4%) showed equivocal initial results. When retested, 178 of the 191 samples (93%) resulted positive for hrHPV on first retest and an additional 8 resulted positive for hrHPV on the second retest, bringing the total positive tests to 186 out of 191 (97.4%). Five samples (2.6%) out of 191 were finally expressed as negative for hrHPV. Corresponding cytologic interpretations for the 191 specimens were as follows: NILM-30, atypical squamous cell of undetermined significance (ASC-US)-138, atypical squamous cells--cannot exclude HSIL-13 (ASC-H-13), LSIL-9, and high-grade squamous intraepithelial lesion (HSIL)-1. Follow-up histology was available for 60 of the 191 equivocal cases and showed cervical intraepithelial neoplasia (CIN) II or CIN III in 7 cases, CIN I in 13 cases, and negative or reactive changes in 40 cases. CONCLUSIONS: On the basis of the results, repeat testing of equivocal specimens might not be necessary as these specimens are overwhelmingly found to be positive for hrHPV. Additionally, hrHPV tests falling in the equivocal range should be considered as definite positive tests, as follow-up results in this cohort demonstrate that significant histologic abnormalities are associated with 10.5% of these cases (20/191), and with 33% of those biopsied (20/60) cases.     

PreTect HPV-Proofer: real-time detection and typing of E6/E7 mRNA from carcinogenic human papillomaviruses

Monitoring human papillomavirus (HPV) E6/E7 mRNA expression may provide an accurate and informative diagnostic approach for detection of oncogene activity related to the development of severe dysplasia or cervical carcinoma. A multiplex nucleic acid sequence based amplification (NASBA) assay, utilizing molecular beacon probes for real-time detection was developed for the identification of E6/E7 mRNA from HPV types 16, 18, 31, 33 and 45. The assay is called PreTect HPV-Proofer and this report describes the development and the analytical performance of the assay. The reproducibility of PreTect HPV-Proofer with regard to a positive result was found to be between 96 and 100%, depending on HPV type. The melting temperature for the different molecular beacons was in the range of 48-55 degrees C, indicating conformational stability, i.e. the molecular beacons will not get activated by the 41 degrees C annealing temperature, but will be activated by the annealing to the target itself. The limit of detection for HPV 16 was ten SiHa or CaSki cells and for HPV 18 one HeLa cell. No cross reactivity was observed with E6/E7 mRNA from the other tested HPV types. mRNA from cervical cells was also successfully amplified after more than one year of storage. In conclusion, the PreTect HPV-Proofer assay, individually identifying E6/E7 mRNA expression from five carcinogenic HPV types, is a reproducible assay that may serve as a valuable tool in monitoring HPV infections producing proteins with a transforming potential.     

Serial quantitation of HPV-16 in the smears of women with mild and moderate dyskaryosis

The aim of this study was to examine the efficacy of semi-quantitative polymerase chain reaction (PCR) testing in cervical smears as an adjunct to cytological surveillance in a cohort of women with mild or moderate dyskaryosis. The study population comprised a group of 62 women who underwent twelve months of cytological and col-poscopic surveillance as part of a larger randomised prospective study of women with mild and moderate dyskaryosis. Semi-quantitative PCR for HPV-16 DNA was carried out on the initial and twelve month study smears before a large loop excision of the transformation zone (LLETZ) was carried out. Smears from a control population which comprised 167 women without a history of abnormal cervical cytology who were attending family planning and general practitioner clinics for routine cervical smears were tested similarly. The presence of high or intermediate levels of HPV-16 DNA on both the initial and twelve month study smear was positively associated with the identification of cervical intraepithelial neoplasia (CIN) grades II or III in the LLETZ specimen (P=0.01). While the combination of HPV-16 DNA testing with cytology on a repeat cervical smear improved the selection of women with underlying CIN II/III, there was still a false negative rate of 53%. Twenty-nine women had ‘low risk’ levels of HPV-16 DNA and mild dyskaryosis or less on both repeat smears indicating suitability for surveillance, but in fact 34% of them had CIN II/III. This study supports the finding reported previously of an association between high and intermediate levels of HPV-16 DNA and CIN II/III. This suggests that semi-quantitative PCR may be a useful adjunct to cytology for selecting those women with mildly abnormal smears who would benefit most from colposcopy. A significant fluctuation in the levels of HPV-16 DNA was not detected when repeated smears were studied, suggesting that serial estimations of HPV-16 levels would add little to cytological examination for the subsequent surveillance of women considered to be at low risk of CIN II/III. © 1995 Wiley-Liss, Inc.