Comparison of the Digene HC2 assay and the Roche AMPLICOR human papillomavirus (HPV) test for detection of high-risk HPV genotypes in cervical samples

Screening Methods for Cervical Cancer

Cervical cancer seriously affects the health of women worldwide. Persistent infection of high-risk HPV (Human Papilloma Virus) can lead to cervical cancer. There is a great need for timely and efficient screening methods for cervical cancer. The current screening methods for cervical cancer are mainly based on cervical cytology and HPV testing. Cervical cytology is made of Pap smear and liquid-based cytology, while HPV testing is based on immunological and nucleic acid level detection methods. This review introduces cervical cancer screening methods based on cytology and human papillomavirus testing in detail. The advantages and limitations of the screening methods are also summarized and compared.

Alternative cytology triage strategies for primary HPV screening

OBJECTIVE

Primary HPV screening programmes for cervical cancer have been implemented in many European countries using a cytology triage. Nonetheless, the optimal cytology triage strategy for minimizing the harms and maximizing the benefits is yet unclear. We identified key characteristics of different algorithms for HPV screening with cytology triage.

METHODS

Using the Finnish randomized HPV screening trial data, we formulated five post-hoc algorithms for HPV screening with a cytology triage, one for HPV screening without a triage and one for cytology screening. Sensitivity, specificity, positive predictive value, colposcopy referral rate and cumulative sensitivity for CIN II + s detected during the first and second screening rounds of the trial were calculated for all algorithms.

RESULTS

In the first screening round, direct referral of HPV positives to colposcopy led to the highest sensitivity (94%) accompanied by the lowest specificity (93%). Following HPV positives up with one repeat screen showed 86% sensitivity and 97% specificity. The corresponding figures with two repeat screens were 84% and 98%. In HPV algorithms, where cytology negative HPV positive individuals had no follow-up, the sensitivities were 65-82% and the specificities 98-99%. The Cytology algorithm had a low sensitivity (69%) with a high specificity (99%). Compared to the first round, the second-round sensitivities were lower and specificities similar or higher.

CONCLUSIONS

The best balance between sensitivity and specificity was achieved by an HPV algorithm with two repeated follow-up tests. However, all HPV algorithms with cytology triage increased colposcopy volume more than the cytology algorithm and thus provoked overdiagnosis.

Limitations and opportunities of technologies for the analysis of cell-free DNA in cancer diagnostics

Cell-free DNA (cfDNA) in the circulating blood plasma of patients with cancer contains tumour-derived DNA sequences that can serve as biomarkers for guiding therapy, for the monitoring of drug resistance, and for the early detection of cancers. However, the analysis of cfDNA for clinical diagnostic applications remains challenging because of the low concentrations of cfDNA, and because cfDNA is fragmented into short lengths and is susceptible to chemical damage. Barcodes of unique molecular identifiers have been implemented to overcome the intrinsic errors of next-generation sequencing, which is the prevailing method for highly multiplexed cfDNA analysis. However, a number of methodological and pre-analytical factors limit the clinical sensitivity of the cfDNA-based detection of cancers from liquid biopsies. In this Review, we describe the state-of-the-art technologies for cfDNA analysis, with emphasis on multiplexing strategies, and discuss outstanding biological and technical challenges that, if addressed, would substantially improve cancer diagnostics and patient care.

Detection of Oral Human Papillomavirus (HPV) and its Clinical Importance

Statement of the Problem

Human papillomavirus (HPV) has a tropism for the squamous epithelium and cause a wide range of diseases, from benign lesions to invasive tumors that can affect the oral cavity.

Purpose

This study aimed to estimate HPV infection in compatible stomatological lesions.

Materials and Method

A cross-sectional study was carried out from March 2017 to August 2019, which included patients who attended the Oral Medicine Department of the School of Dentistry of the University of Buenos Aires who presented oral manifestations compatible with HPV infection that accepted to be studied by histopathology and determination of viral genotype by polymerase chain reaction (PCR). The study was carried out from the biopsy fixed in formalin and included in paraffin, for histopathological study and the genotypification of HPV by genotype-specific PCR and/or sequencing of the L1 fragment. To confirm the negative cases hybrid capture method was also used. The 95% OR-IC was estimated.

Results

108 patients, 76 women and 32 men were studied, who underwent a clinical stomatological examination and genotyping of HPV (PCR-specific genotype), being positive for 60 patients and negative for 48. Among the positive cases (n= 60) 46.7% (n= 28) corresponded to elevated lesions infected with high-risk HPV genotypes, 43.3% (n= 26) to elevated lesions with low-risk HPV genotypes, regarding flat lesions it was found that 5% (n=3) corresponded with high-risk HPV genotypes and another 5% (n=3) with low-risk genotypes, with OR 1,076 95% CI (0.1993-5.818). The HPV genotypes found were 2, 6, 11, 13, 16, 18, 26, 31, 32, 33, 35, 51, 58, 64 and 72.

Conclusion

Our results estimated an association between white, bright, and elevated oral lesions and the presence of high-risk HPV.

Split-type electrochemiluminescent gene assay platform based on gold nanocluster probe for human papillomavirus diagnosis

Persistent high-risk human papillomavirus (HPV) infection is the leading cause of cervical cancer. Efficient detection of HPV16 E7 is necessary for early diagnosis and cure of the disease. Here, a novel and high-performance Au nanocluster (AuNC) probe-based split-type electrochemiluminescent (ECL) assay platform has been established to detect these oncogenes, in which the nucleic acid hybridization assay and the ECL measurements are performed independently. The proposed approach combines superior magnetic nanobead enrichment and separation technology, specific nucleic acid hybridization technology, and high-efficiency AuNC probe ECL strategy, and shows excellent advantages. First, the split-type ECL sensing platform can effectively avoid interference from biological samples and adequately uses the ECL efficiency of the AuNC probe. Furthermore, the ultrahigh sensitivity assay of HPV DNA can be achieved without any complex nucleic acid amplification technique. Taking advantage of the above merits of split-type detection, the ECL DNA sensor achieved ideal low detection of 6.8 aM and a wide dynamic range bridging 10 orders of magnitude HPV16 E7. Furthermore, together with its favorable and powerful specificity, high sensitivity, and good selectivity, this strategy could detect HPV16 E7 DNA in human samples, which showed great consistency with the FDA-approved approach (Hybrid capture 2, HC2). Therefore, this work proposes a facile and reliable split-type ECL platform for HPV diagnosis and shows great potential for the early diagnosis of other diseases.

Elimination of cervical cancer in Tanzania: Modelled analysis of elimination in the context of endemic HIV infection and active HIV control

The World Health Organisation (WHO) has launched a strategic initiative for cervical cancer (CC) elimination which involves scaling up three interventions: human papillomavirus (HPV) vaccination, twice-lifetime HPV-screening screening and pre-cancer/cancer treatment by 2030. CC is challenging to control in countries with endemic human immunodeficiency virus (HIV), as women living with HIV (WLHIV) are at elevated risk of HPV infection, persistence and progression. This analysis estimated the impact of the elimination interventions on CC incidence and mortality but additionally considered more intensive screening for WLHIV, using Tanzania as an example. A dynamic HIV/HPV model was used to simulate the elimination strategy for vaccination, screening and pre-cancer/cancer treatment, with 3-yearly HPV-screening in WLHIV starting at age 25 years, in the context of sustained HIV control in Tanzania from 2020 to 2119. Without vaccination or HPV screening, CC incidence rates per 100 000 women are predicted to fall from 58.0 in 2020 to 41.6 (range: 39.1-44.7) in 2119, due to existing HIV control. HPV vaccination and twice-lifetime HPV-screening for the general population and 3-yearly screening for WLHIV, would reduce CC incidence to 1.3 (range: 1.3-2.5) by 2119, with elimination (<4/100 000) in 2076 (range: 2076-2092). CC mortality rates per 100 000 women are predicted to reach 1.1 (range: 1.1-2.1) with further reductions contingent on increased CC treatment access. Vaccination and 3-yearly HPV-screening for WLHIV is predicted to achieve elimination in the subgroup of WLHIV potentially as early as 2061 (range: 2061-2078), with a 2119 CC incidence rate of 1.7 (range: 1.7-3.3). Scaling-up vaccination and HPV-screening will substantially reduce CC incidence in Tanzania, with elimination predicted within a century. Three-yearly HPV-screening and HPV vaccination, at high coverage rates, would facilitate CC elimination among WLHIV, and thus accelerate elimination in the overall population.

Human Papillomavirus Genome based Detection and Typing: A Holistic Molecular Approach

Human Papillomavirus (HPV) is a species specific double-stranded DNA virus infecting human cutaneous or mucosal tissues. The genome structure of HPV is extremely polymorphic hence making it difficult to discriminate between them. HPV exhibits numerous dissimilar types that can be subdivided into high-risk (HR), probably high-risk and low-risk (LR), causing numerous types of cancers and warts around the genital organs in humans. Several screening methods are performed in order to detect cytological abnormalities and presence or absence of HPV genome. Currently available commercial kits and methods are designed to detect only a few HR/LR-HPV types, which are expensive adding to the economic burden of the affected individual and are not freely available. These gaps could be minimized through Polymerase Chain reaction (PCR) method, which is a gold standard and a cost-effective technique for the detection of most HPV (both known and unknown) types by using specific consensus primers in minimal lab setup. In this context, numerous studies have validated the effectiveness of different sets of consensus primers in the screening of HPVs. Numerous consensus primers, such as E6, E6/E7, GP-E6/E7, MY09/11, GP5+/GP6+, SPF10, and PGMY09/11 have been developed to detect the presence of HPV DNA. In addition, HPV detection sensitivity could be achieved through consensus primer sets targeting specific ORF regions like L1 and E6, which may finally assist in better diagnosis of several unknown HR-HPVs. The present review, provides a summary of the available methods, kits and consensus primer sets for HPV genome based detection, their advantages and limitations along with future goals to be set for HPV detection.

Amplification chemistries in clinical virology

Molecular diagnostic methods have evolved and matured considerably over the last several decades and are constantly being evaluated and adopted by clinical laboratories for the identification of infectious pathogens. Advancement in other technologies such as fluorescence, electronics, instrumentation, automation, and sensors have made the overall diagnostic process more accurate, sensitive, and rapid. Nucleic acid based detection procedures, which rely on the fundamental principles of DNA replication have emerged as a popular and standard diagnostic method, and several commercial assays are currently available based on different nucleic acid amplification techniques. This review focuses on the major amplification chemistries that are used for developing commercial assays and discusses their application in the clinical virology laboratory.

Colorimetric human papillomavirus DNA assay based on the retardation of avidin-induced aggregation of gold nanoparticles

A colorimetric assay for human papillomavirus (HPV) DNA was developed based on the retardation of the avidin-induced aggregation of gold nanoparticles (AuNPs) by HPV DNA. Positively charged avidin acts as a coagulant for AuNP aggregation. In the presence of the target DNA, however, the aggregation of AuNPs is retarded owing to electrosteric stabilization as a result of the hybridization of the target and probe DNA. In the absence of HPV DNA, the stabilization effect caused by the biotinylated probe DNA is weak, resulting in NP aggregation and a color change from red to purple. Aggregation may be easily observed with bare eyes or spectrophotometrically at about 560 nm. The visual detection limit is 1 nM. The assay was used for the determination of HPV DNA after polymerase chain reaction (PCR) amplification without any further purification. Graphical abstract Schematic presentation of the avidin-induced aggregation of unmodified gold nanoparticles (AuNPs) which leads to a color change from red to purple. In the presence of dsDNA, however, the aggregation is remarkably retarded.

Self- versus physician-collected samples for the follow-up of human papillomavirus-positive women in sub-Saharan Africa

Introduction

Human papillomavirus (HPV) testing is a suitable tool for primary cervical cancer (CC) screening and follow-up in low-resource settings. Vaginal samples taken by women themselves (Self-HPV) are an interesting alternative to physician-performed sampling (Dr-HPV). Our aim was to assess the performance of Self-HPV and Dr-HPV at 6 and 12 months following a CC screening campaign.

Methods

This study was carried out at the Dschang District Hospital, Cameroon. Women aged 30–49 years were recruited in a CC screening campaign. HPV-positive women, of whom 2/3 were treated with thermoablation because of abnormal results at baseline screening, were invited to participate in a follow-up study. Self- and Dr-HPV, as well as cytology, were performed at 6 and 12 months. HPV samples were analyzed using the Xpert HPV assay. Sensitivity and specificity for the detection of low-grade squamous intraepithelial lesion or worse and of high-grade squamous intraepithelial lesion or worse were calculated for Self-HPV and Dr-HPV, using cytology as the reference diagnosis.

Results

Overall, 188 HPV-positive women were invited to attend follow-up. The obtained follow-up visits’ attendance was 154 (81.9%) and 131 (69.7%) at 6 and 12 months, respectively. While the overall performance of Dr-HPV at 6 months was slightly superior, Self-HPV showed an improved sensitivity for HSIL+ detection at 12 months when compared with Dr-HPV (83.3% [95% CI 41.8–98.9] versus 71.4% [95% CI 21.5–95.8], respectively). The overall HPV positivity agreement between Self- and Dr-HPV at 6 and 12 months corresponded to a κ value of 0.62 and 0.52, respectively. Among women treated with thermoablation (n=121) at baseline screening, Self-HPV was as sensitive as Dr-HPV, although less specific (P=0.003).

Conclusion

Self-HPV is a valuable tool for the follow-up of HPV-positive women in low-resource settings. Larger, randomized trials are needed to confirm the validity of our findings.

Comparison of DNA testing strategies in monitoring human papillomavirus infection prevalence through simulation

BACKGROUND

HPV DNA diagnostic tests for epidemiology monitoring (research purpose) or cervical cancer screening (clinical purpose) have often been considered separately. Women with positive Linear Array (LA) polymerase chain reaction (PCR) research test results typically are neither informed nor referred for colposcopy. Recently, a sequential testing by using Hybrid Capture 2 (HC2) HPV clinical test as a triage before genotype by LA has been adopted for monitoring HPV infections. Also, HC2 has been reported as a more feasible screening approach for cervical cancer in low-resource countries. Thus, knowing the performance of testing strategies incorporating HPV clinical test (i.e., HC2-only or using HC2 as a triage before genotype by LA) compared with LA-only testing in measuring HPV prevalence will be informative for public health practice.

METHOD

We conducted a Monte Carlo simulation study. Data were generated using mathematical algorithms. We designated the reported HPV infection prevalence in the U.S. and Latin America as the "true" underlying type-specific HPV prevalence. Analytical sensitivity of HC2 for detecting 14 high-risk (oncogenic) types was considered to be less than LA. Estimated-to-true prevalence ratios and percentage reductions were calculated.

RESULTS

When the "true" HPV prevalence was designated as the reported prevalence in the U.S., with LA genotyping sensitivity and specificity of (0.95, 0.95), estimated-to-true prevalence ratios of 14 high-risk types were 2.132, 1.056, 0.958 for LA-only, HC2-only, and sequential testing, respectively. Estimated-to-true prevalence ratios of two vaccine-associated high-risk types were 2.359 and 1.063 for LA-only and sequential testing, respectively. When designated type-specific prevalence of HPV16 and 18 were reduced by 50 %, using either LA-only or sequential testing, prevalence estimates were reduced by 18 %.

CONCLUSION

Estimated-to-true HPV infection prevalence ratios using LA-only testing strategy are generally higher than using HC2-only or using HC2 as a triage before genotype by LA. HPV clinical testing can be incorporated to monitor HPV prevalence or vaccine effectiveness. Caution is needed when comparing apparent prevalence from different testing strategies.

Development and application of a rapid detection system for human papillomavirus and Herpes simplex virus-2 by loop-mediated isothermal amplification assay

Human papillomavirus (HPV) infection is an important factor that causes cervical cancer and non-melanoma skin cancer (NMSC), while HSV-2 plays an important role when HR-HPV triggers the cancer. Thus, a quick and convenient assay in the detection of HPV and HSV-2in the screening of HPV and HSV-2 infection is required. Two respective HPV and HSV-2 detection methods were established based on loop-mediated isothermal amplification (LAMP) assay. Specific outer primers, inner primers, and loop primers were designed according to the conserved domains of HPV and HSV-2 genomes, respectively, while degenerate primers were used for HPV assay. After optimizing the reaction conditions, the results were observed by LAMP Tubidimeter real-time LA-320. Standard plasmids HPV-L-P and HSV-2-L-P were cloned and used in sensitivity tests of HPV LAMP and HSV-2 LAMP, respectively. Fifty samples of actinic keratosis (AK), 20 samples of squamous cell carcinoma (SCC), 50 samples of basal cell carcinoma (BCC) and 20 samples of seborrheic keratosis (SK) were detected by HPV assay. Seventy three clinical samples of vaginitis, chronic cervicitis, cervical intraepithelial neoplasias and cervical cancer level positive were detected with HPV and HSV-2 assays. The reaction conditions of two assays were the same with a reaction temperature of 63 °C and a reaction time of 45 min. The sensitivity of HPV LAMP assay was 10 copies/μL, while that of the HSV-2 LAMP assay was 100 copies/μL. No cross-reactivity was observed. The HPV positive rates of AK, SCC, BCC and SK samples were 80% (40/50), 75% (15/20), 44% (22/50) and 21% (15/72), respectively. As an economic and quick diagnostic tool, LAMP assay is conducive to the extensive screening of HPV and HSV-2 and has huge potential to be promoted in resource-limited hospitals.

Low initial human papillomavirus viral load may indicate worse prognosis in patients with cervical carcinoma treated with surgery

Objective

To evaluate the prognostic implication of human papillomavirus (HPV) viral load in cervical cancer patients who underwent radical hysterectomy.

Methods

We conducted a retrospective review of patients with stage IA2 through stage IIIA cervical carcinoma who underwent radical hysterectomy at Sun Yat-sen University Cancer Center between January 2005 and December 2009. Patients who had undergone preoperative hybrid capture 2 testing to detect HPV DNA were included. A total of 346 patients positive for HPV DNA were enrolled and stratified into two groups according to the median HPV viral load.

Results

HPV viral load was significantly correlated with lymphovascular space invasion (p=0.026) and deep stromal invasion (p=0.024). However, other factors, such as age, stage, histologic grade, histologic type, lymph node metastasis, and tumor size, were not significantly associated with viral load. Low HPV viral load was correlated with poor disease-free survival in univariate analysis (p=0.037) and multivariate analysis (p=0.027). There was no significant difference in overall survival with regard to initial HPV viral load.

Conclusion

Low initial HPV viral load may be a poor prognostic factor for cervical cancer patients who have undergone radical hysterectomy.

A Comparison of the Roche Cobas HPV Test With the Hybrid Capture 2 Test for the Detection of High-Risk Human Papillomavirus Genotypes

Context

All Food and Drug Administration–approved methods in the United States for human papillomavirus testing including the Hybrid Capture 2 human papillomavirus assay and the Roche cobas human papillomavirus test are approved for cytology specimens collected into ThinPrep media but not for specimens collected into SurePath solution.

Objective

To compare the performance of the Roche cobas and Hybrid Capture 2 tests for the detection of high-risk human papillomavirus using both ThinPrep and SurePath preparations as part of a validation study.

Design

One thousand three hundred seventy-one liquid-based cytology samples, including 1122 SurePath and 249 ThinPrep specimens, were tested for high-risk human papillomavirus DNA using the Roche cobas human papillomavirus test and the Hybrid Capture 2 human papillomavirus assay. For cases with discrepant results, confirmatory testing was performed using Linear Array human papillomavirus testing.

Results

One hundred and fifty-six (11.38%) and 184 (13.42%) of the 1371 specimens tested positive for high-risk human papillomavirus DNA using the Hybrid Capture 2 human papillomavirus assay and Roche cobas human papillomavirus assay, respectively. In addition, 1289 (94.0%) of 1371 specimens demonstrated concordant high-risk human papillomavirus results with a κ value of 0.72 (95% confidence interval, 065–0.78). There was no statistically significant difference in the percentage of positive high-risk human papillomavirus results between the 2 liquid-based preparations with either assay. Discordant results between the 2 assays were noted in 82 of 1371 cases (6%). Twenty-seven of 82 cases (32.9%) were Hybrid Capture 2 positive/Roche cobas negative and 55 of 82 cases (67.1%) were Roche cobas positive/Hybrid Capture 2 negative. Two of 20 Hybrid Capture 2–positive/Roche cobas–negative cases (10%) and 26 of 37 Roche cobas–positive/Hybrid Capture 2–negative cases (70%) tested positive for high-risk human papillomavirus by Linear Array.

Conclusions

Both assays showed good agreement and excellent specificity with either ThinPrep or SurePath preparations. The number of discordant results was relatively small. The performance of both assays was similar for ThinPrep specimens, but the Roche cobas test demonstrated higher sensitivity with SurePath specimens.

Comparison of Analytical and Clinical Performance of HPV 9G DNA Chip, PANArray HPV Genotyping Chip, and Hybrid-Capture II Assay in Cervicovaginal Swabs

Background:

Human papillomavirus (HPV) infection can be detected by using several molecular methods, including Hybrid-Capture II (HC2) assay and variable HPV DNA chip tests, although each method has different sensitivities and specificities.

Methods:

We performed HPV 9G DNA Chip (9G) and PANArray HPV Genotyping Chip (PANArray) tests on 118 cervicovaginal swabs and compared the results with HC2, cytology, histology, and direct sequencing results.

Results

The overall and high-risk HPV (HR-HPV) positivity rates were 62.7% and 44.9% using 9G, and 61.0% and 30.5% using PANArray, respectively. The positivity rates for HR-HPV with these two chips were significantly lower than 55.1% when HC2 was used. The sensitivity of overall HPV positivity in detecting histologically confirmed low-grade cervical squamous intraepithelial lesions or higher was 88.7% for all three tests. The specificity was 58.5% for 9G and 61.5% for PANArray, which was significantly lower than the 72.3% for HC2. With the HR-HPV⁺ genotype threshold, the sensitivity decreased to 75.5% for 9G and 52.8% for PANArray, which was significantly lower than the 88.7% for HC2. Comparison of the two chips showed concordant results in 55.1% of the samples, compatible results in 16.9%, and discordant results in 28.0%, exhibiting poor agreement in detecting  certain HPV genotypes. Compared with direct sequencing, 9G yielded no discordant results, whereas PANArray yielded 31 discordant results (26.7%).

Conclusions

Compared with HC2, the HPV genotyping tests showed lower sensitivity in histologic correlation. When the two chips were compared, the 9G was more sensitive and accurate for detecting HR-HPV than the PANArray.

Expression of Yes-associated protein in cervical squamous epithelium lesions

OBJECTIVE

Yes-associated protein (YAP) was defined as a candidate oncogene in multiple cancers. Yet, the role of YAP in cervical cancer is largely unknown. The aim of this study was to determine whether YAP could be used as a predictive biomarker in cervical precancerous lesions.

METHODS

Immunohistochemical analysis of YAP expression was performed in 10 chronic cervicitis, 49 cervical intraepithelial neoplasia (CIN) 1, 55 CIN 2, 34 CIN 3, and 32 cervical squamous cell carcinoma (SCC) samples. Human papillomavirus (HPV) was detected by HPV genotype detection kit in 70 cases including 10 chronic cervicitis cases, 13 CIN 1 cases, 19 CIN 2 cases, 14 CIN 3 cases, and 14 SCC cases. Furthermore, the relationship between YAP expression and HPV integration status was analyzed using Spearman rank correlation coefficient test.

RESULT

Samples of chronic cervicitis had negative or weak expression of YAP in cytoplasm. In the CIN 1 group, YAP expression was primarily confined to the lower third part of squamous epithelia or basal layer, whereas higher-grade CIN (2 and 3) and SCC groups had a strong nuclear expression of YAP. The expression levels of YAP in chronic cervicitis and CIN 1 were significantly lower compared to those in higher-grade CIN and SCC. Moreover, YAP expression was correlated with HPV integration status. Most high-risk HPV(+)/YAP(+) cases were found in the CIN 3 and SCC groups.

CONCLUSION

This study suggested that YAP could function as a predictive marker in CIN and cervical cancer. YAP expression, in combination of HPV, might facilitate the identification of precancerous cervical lesions.

Evaluation of using composite HPV genotyping assay results to monitor human papillomavirus infection burden through simulation

Background

Researchers often group various HPV types into composite measures based on vaccine subtypes, oncogenic potential, or phylogenetic position. Composite prevalence estimates based on PCR genotyping assay results have been calculated to assess HPV infection burden and to monitor HPV vaccine effectiveness. While prevention and intervention strategies can be made based on these prevalence estimates, the discussion on how well these prevalence estimates measure the true underlying infection burdens is limited.

Methods

A simulation study was conducted to evaluate accuracy of using composite genotyping assay results to monitor HPV infection burden. Data were generated based on mathematical algorithms with prespecified type-specific infection burdens, assay sensitivity, specificity, and correlations between various HPV types. Estimated-to-true prevalence rate ratios and percent reduction of vaccine types were calculated.

Results

When “true” underlying type-specific infection burdens were prespecified as the reported prevalence in U.S. and genotyping assay with sensitivity and specificity (0.95, 0.95) was used, estimated-to-true infection prevalence ratios were 2.35, 2.29, 2.18, and 1.46, for the composite measures with 2 high-risk vaccine, 4 vaccine, 14 high-risk and 37 HPV types, respectively. Estimated-to-true prevalence ratios increased when prespecified “true” underlying infection burdens or assay specificity declined. When prespecified “true” type-specific infections of HPV 6, 11, 16 and 18 were reduced by 50%, the composite prevalence estimate of 4 vaccine types only decreased by 17% which is much lower than 48% reduction in the prespecified “true” composite prevalence.

Conclusions

Composite prevalence estimates calculated based on panels of genotyping assay results generally over-estimate the “true” underlying infection burdens and could under-estimate vaccine effectiveness. Analytical specificity of genotyping assay is as or more important than analytical sensitivity and should be considered in selecting assay to monitor HPV.

From Human Papillomavirus (HPV) Detection to Cervical Cancer Prevention in Clinical Practice

The newly gained knowledge of the viral etiology in cervical carcinogenesis has prompted industrial interests in developing virology-based tools for cervical cancer prevention. Due to the long incubation period from viral infection to developing an invasive cancer, a process whose outcome is influenced by numerous life-style and genetic factors, the true efficacy of the genotype-specific human papillomavirus (HPV) vaccines in cervical cancer prevention cannot be determined for another 30 years. Most HPV DNA test kits designed to replace the traditional Papanicolaou (Pap) smears for precancer detection lack the analytical sensitivity and specificity to comprehensively detect all potentially carcinogenic HPVs and to perform reliable genotyping. The authors implemented the classic nested PCR and Sanger DNA-sequencing technology for routine HPV testing. The results showed a true negative HPV PCR invariably indicates the absence of precancerous cells in the cytology samples. However, 80.5% of single positive HPV-16 tests and 97.3% of single positive HPV-18 tests were associated with a negative or a largely self-reversible Pap cytology. Routine sensitive and reliable HPV type-specific or perhaps even variant-specific methods are needed to address the issues of persistence of HPV infection if a virology-based primary cervical screen is used to replace the Pap cytology screening paradigm.

Comparison of digene hybrid capture 2, GeneMatrix PapilloScreen, and a PCR sequencing assay in detecting high-risk and probable high-risk oncogenic HPV genotypes in specimens from Korean women

Most cervical cancers are caused by 15 high-risk (HR) and three probable high-risk (pHR) oncogenic types of human papillomavirus (HPV). However, current commercial HR HPV screening test products do not include pHR HPV genotypes. Recently, PapilloScreen has been developed to detect the 15 HR and three pHR HPV types. In this study, we evaluated the concordance levels and clinical performance of Hybrid Capture 2 (HC2), PapilloScreen, and a PCR sequencing assay in detecting HR and pHR HPV. The PapilloScreen (96.8 %) and PCR sequencing assay (96.8 %) demonstrated higher sensitivity than HC2 (80.7 %) for detecting HR and pHR HPV. The three assays showed similar specificities and positive or negative predictive values. The concordance levels were 86.5 % (κ = 0.68) and 86.5 % (κ = 0.67) between HC2 and PapilloScreen and between HC2 and PCR sequencing, respectively. A near-perfect concordance was observed between PapilloScreen and PCR sequencing (97.8 %, κ = 0.95). Overall, the agreement between the three assays suggests that the results obtained by the HC2 assay are more often discordant (12.6 %) than the PCR-based tests. In conclusion, PapilloScreen is highly sensitive for detecting high-grade CIN or cervical cancer. The PapilloScreen assay should be considered an accurate and sensitive method for detecting HR and pHR HPV infections and an epidemiological tool for prevalence studies as well as early diagnosis and intervention in HR and pHR HPV infections.

Comparison of the performance of carcinogenic HPV typing of the Roche Linear Array and Qiagen LiquiChip® HPV assays

BACKGROUND

Cervical cancer is caused by high-risk types of human papillomavirus (HPV). DNA testing of such high-risk types of HPV could improve cervical screening.The aim of the study was to compare the sensitivities and positive predictive values of two commercially available typing assays (Qiagen LQ and Roche LA) and to comparatively assess the distribution of HPV types with these two assays.

METHODS

The study population comprised 311 ASCUS + women with abnormal pap tests who were HCII positive and who were admitted to three European referral gynecology clinics between 2007 and 2010 (Madrid, Marseille and Milan). All patients underwent LQ and LA tests.

RESULTS

The sensitivity of the two assays for HPV typing was 94% for LQ and 99% for LA (compared with HCII). The overall concordance between LQ and LA was 93%. The three prevalent genotypes, HPV16, HPV18, and HPV31, were identified with a high concordance using the two assays: kappa 0.93, 0.83, and 0.91, respectively. Mixed genotypes were more frequently detected by LA than by LQ: 52% vs. 18%, respectively (p < .0001).

CONCLUSIONS

These assays have a good clinical sensitivity for detecting HPV types in CIN2+ patients and allow the virus type to be detected in the same experiment. Our study revealed no significant difference between LQ and LA for CIN2+ or CIN3+ diagnosis, indicating similar distributions of HPV types and a mixed genotype detection that is higher for LA than for LQ.

High-resolution melting molecular signatures for rapid identification of human papillomavirus genotypes

Background

Genotyping of human papillomarvirus (HPV) is crucial for patient management in a clinical setting. This study accesses the combined use of broad-range real-time PCR and high-resolution melting (HRM) analysis for rapid identification of HPV genotypes.

Methods

Genomic DNA sequences of 8 high-risk genotypes (HPV16/18/39/45/52/56/58/68) were subject to bioinformatic analysis to select for appropriate PCR amplicon. Asymmetric broad-range real-time PCR in the presence of HRM dye and two unlabeled probes specific to HPV16 and 18 was employed to generate HRM molecular signatures for HPV genotyping. The method was validated via assessment of 119 clinical HPV isolates.

Results

A DNA fragment within the L1 region was selected as the PCR amplicon ranging from 215–221 bp for different HPV genotypes. Each genotype displayed a distinct HRM molecular signature with minimal inter-assay variability. According to the HRM molecular signatures, HPV genotypes can be determined with one PCR within 3 h from the time of viral DNA isolation. In the validation assay, a 91% accuracy rate was achieved when the genotypes were in the database. Concomitantly, the HRM molecular signatures for additional 6 low-risk genotypes were established.

Conclusions

This assay provides a novel approach for HPV genotyping in a rapid and cost-effective manner.

Comparison of the Abbott RealTime High-Risk Human Papillomavirus (HPV), Roche Cobas HPV, and Hybrid Capture 2 assays to direct sequencing and genotyping of HPV DNA

Infection with high-risk (HR) human papillomavirus (HPV) genotypes is an important risk factor for cervical cancers. We evaluated the clinical performances of two new real-time PCR assays for detecting HR HPVs compared to that of the Hybrid Capture 2 test (HC2). A total of 356 cervical swab specimens, which had been examined for cervical cytology, were assayed by Abbott RealTime HR and Roche Cobas HPV as well as HC2. Sensitivities and specificities of these assays were determined based on the criteria that concordant results among the three assays were regarded as true-positive or -negative and that the results of genotyping and sequencing were considered true findings when the HPV assays presented discrepant results. The overall concordance rate among the results for the three assays was 82.6%, and RealTime HR and Cobas HPV assays agreed with HC2 in 86.1% and 89.9% of cases, respectively. The two real-time PCR assays agreed with each other for 89.6% of the samples, and the concordance rate between them was equal to or greater than 98.0% for detecting HPV type 16 or 18. HC2 demonstrated a sensitivity of 96.6% with a specificity of 89.1% for detecting HR HPVs, while RealTime HR presented a sensitivity of 78.3% with a specificity of 99.2%. The sensitivity and specificity of Cobas HPV for detecting HR HPVs were 91.7% and 97.0%. The new real-time PCR assays exhibited lower sensitivities for detecting HR HPVs than that of HC2. Nevertheless, the newly introduced assays have an advantage of simultaneously identifying HPV types 16 and 18 from clinical samples.

Comparison of the f-HPV typing™ and Hybrid Capture II® assays for detection of high-risk HPV genotypes in cervical samples

Human papillomavirus genotyping is being considered in cervical screening programs and for monitoring the effectiveness of HPV vaccination. Both approaches require access to fast, easy and high-throughput technology. The aim of this study was to compare a new commercial assay (f-HPV typing™) with the Hybrid Capture II® (HC2) to detect HPV infection. The F-HPV typing is a multiplex fluorescent PCR method recognizing E6 and E7 regions of 13 high-risk (HR) HPV types, the same set of HR-types targeted HC2 test. A subset of 157 cervical samples was tested with both assays. The percentage of positive HR-HPV DNA samples was 24% (37/155) by HC2 and 33% (49/155) by f-HPV typing. Concordant results were found in 133/155 (overall agreement, 85.8%; Cohen's kappa=0.65). The analytical sensitivity and specificity of f-HPV were 97.6 and 93, respectively. In conclusion, this study shows that the f-HPV assay provides a good alternative to HC2 to detect HPV infection, allowing simple and rapid HPV genotyping and detecting multiple infections.

Population-based human papillomavirus 16, 18, 6 and 11 DNA positivity and seropositivity in Chinese women

To optimize HPV vaccination implementation at the population-level in China, data are needed on age-specific HPV 16, 18, 6 and 11 prevalence. This cross-sectional, population-based study evaluated the age- and type-specific HPV 16, 18, 6 and 11 prevalence of DNA and serum antibodies among women in China. From July 2006 to April 2007, 17-54 year old women from three rural provinces (Xinjiang, Shanxi and Henan) and two cities (Beijing and Shanghai) provided cervical exfoliated cells for HPV DNA and liquid-based cervical cytology (SurePath). High- and low-risk HPV types were detected with HC-II (Qiagen), with genotyping of HPV-positive samples using Linear Array (Roche). HPV 16, 18, 6 and 11 serum antibodies were detected using a Luminex-based, competitive immunoassay (Merck). A total of 4,206 women with DNA and serum antibody results were included. HPV 16 DNA prevalence peaked in women aged 30-34 (4.2%) and 45-49 yr (3.8%), while HPV 18 DNA prevalence peaked at ages 40-44 yr (1.3%). Most women were dually DNA and serum antibody negative: HPV 16 (92.2%), 18 (97.2%), HPV 16 and 18 (90.2%), 6 (92.0%), 11 (96.6%), 6 and 11(89.9%) and HPV 16, 18, 6 and 11 (82.5%). Future national HPV vaccination programs in China should target younger women due to increased exposure to HPV types 16, 18, 6 and 11 with increasing age. Cumulative exposure of HPV may be underreported in this population, as cross-sectional data do not accurately reflect exposure to HPV infections over time.

Performance of a New HPV Cervi-Collect Collection and Transportation Kit

Background. Liquid-based Pap (L-Pap) media are used for Pap and human papillomavirus (HPV) testing. Objectives. To compare RealTime High Risk (HR) HPV testing of a new collection kit (Cervi-Collect) and PreservCyt L-Pap specimens. To determine ease of use and safety of Cervi-Collect. Methods. L-Pap samples (n = 203) were tested with HC2 and RealTime HR HPV and Cervi-Collect with RealTime HR HPV. Discordant samples were genotyped. Results. L-Pap and Cervi-Collect specimens tested by RealTime HR HPV showed 93.1% agreement (Kappa 0.86). RealTime HR HPV and HC2 on L-Pap had 90.3% agreement (Kappa 0.80). RealTime HR HPV on Cervi-Collect and HC2 on L-Pap showed 88.2% agreement (Kappa 0.76). Sixteen of 21 samples which were HC2 negative and RealTime HR HPV positive on L-Pap or Cervi-Collect contained HR HPV genotypes. Eleven healthcare collectors were in strong agreement on a usability and safety questionnaire. Conclusion. Cervi-Collect samples were easy to collect and showed strong agreement with L-Pap samples tested with RealTime HR HPV or HC2.

Analytical comparison of the cobas HPV Test with Hybrid Capture 2 for the detection of high-risk HPV genotypes

Human papillomavirus (HPV) is a causal agent of cervical cancer, and persistent HPV16 or HPV18 infection carries a particularly high risk. The cobas HPV Test (cobas) provides individual HPV16/HPV18 genotyping with a simultaneous result for 12 other high-risk HPV (hrHPV) genotypes. Its analytical performance for hrHPV genotype detection was retrospectively evaluated against the digene Hybrid Capture 2 HPV DNA test (HC2), in three European centers, in 1360 cervical samples. Both HPV tests performed similarly, with no significant difference in the number of positive and negative samples identified by each test and good agreement between the tests was observed. Discordant samples were analyzed with the Linear Array HPV genotyping test. More low-risk HPV (lrHPV) genotypes were detected in HC2-positive/cobas-negative samples compared with HC2-negative/cobas-positive samples. Conversely, more hrHPV genotypes were detected in HC2-negative/cobas-positive samples compared with HC2-positive/cobas-negative samples. Eight HC2-negative/cobas-positive samples were positive for HPV16 compared with five HC2-positive/cobas-negative samples; HPV18 was detected in one HC2-negative/cobas-positive sample and one HC2-positive/cobas-negative sample. The cobas HPV Test demonstrates comparable analytical performance to the HC2 test, but with a lower rate of cross-reactivity with lrHPV genotypes, and has the advantage of simultaneously providing HPV16/HPV18 identification.

Comparative performance of human papillomavirus DNA testing using novel sample collection methods

To explore alternative cervical cancer screening approaches in an underserved population, we compared the performance of human papillomavirus (HPV) DNA assays in combination with different sample collection methods for primary cervical screening in the Mississippi Delta region. Three specimens were collected from women aged 26 to 65 years who were either routinely undergoing screening (n = 252) or not (n = 191): clinician-collected cervical specimens, clinician-collected cervicovaginal specimens, and self-collected cervicovaginal specimens taken at home. A novel collection device and medium were used for cervicovaginal sampling. Specimens were tested by three HPV DNA assays: hybrid capture 2 (HC2; Qiagen Corp., Gaithersburg, MD), Linear Array (LA; Roche Molecular Systems, Pleasanton, CA), and Amplicor (Roche Molecular Systems, Pleasanton, CA). Liquid-based cytology was performed on cervical specimens. We compared the overall positivity (a proxy for clinical specificity) for any carcinogenic HPV genotype and calculated the agreement across assay and specimen type using McNemar's test for differences in test positivity. Across all three assays there were no significant differences between clinician-collected and self-collected cervicovaginal specimens (P > 0.01 for all comparisons). For both cervicovaginal specimens (clinician collected and self-collected), fewer women tested positive by HC2 than by LA or Amplicor (P < 0.01 for all comparisons). HC2 had the best agreement between specimens for all assays. HC2 is likely more clinically specific, although possibly less sensitive, than either PCR test. Thus, use of HC2 on cervicovaginal specimens for screening could result in fewer referrals compared to LA and Amplicor.

High risk human papillomavirus genotyping in clinical samples: evaluation of different commercial tests

The aim of the present study is to compare the performance of several commercial human papillomavirus (HPV) tests in a cohort of 281 women. The hybrid capture II, the PreTect-HPV-Proofer, the linear array, and DR.HPVTMIVD were utilized to detect and type HPV in parallel with in-house PCR tests followed by direct automated sequencing or by sub-cloning and sequencing. The concordance levels along with other tests were evaluated with a Cohen's K value varying between 0.60 to 0.88, indicating good correlation with nearly perfect agreement between hybrid capture II, (HCII) and the linear array test. High sensitivity was recorded by the linear array and HCII with 100% (95% CI, 0.8021 to 1.0000) detection of cervical intraepithelial neoplasia (CIN) III by both methods. Conversely, the PreTect-HPV-Proofer showed high specificity with 12% (95% CI, 0.7966 to 0.9163) positivity on normal samples. The genotyping analysis showed that agreement among tests was only low to moderate with great differences between different HPV types. Multiple infections were detected with poor concordance and sub-cloning assays revealed the presence of a lower number of HPV in comparison to the other methods. In summary, the use of different HPV tests applied to the same group of cervical smears may possibly lead to incongruent results, suggesting the need to standardize type-specific sensitivity of genotyping methods and the need to evaluate their accuracy in detecting multiple HPV infections. This would be a prerequisite for the use of genotyping assays in cervical cancer screening programs.

Comparison of real-time multiplex human papillomavirus (HPV) PCR assays with the linear array HPV genotyping PCR assay and influence of DNA extraction method on HPV detection

Real-time human papillomavirus (HPV) type-specific multiplex PCR assays were developed to detect HPV DNA in specimens collected for the efficacy determination of the quadrivalent HPV (type 6, 11, 16, and 18) L1 virus-like particle (VLP) vaccine (Gardasil). We evaluated the concordance between type-specific multiplex HPV PCR and the widely used, commercially available Roche Linear Array genotyping PCR assay. Female genital swab specimens were tested for the presence of L1, E6, and E7 sequences of HPV type 6 (HPV6), HPV11, HPV16, HPV18, HPV31, HPV45, HPV52, and HPV58 and E6 and E7 sequences of HPV33, HPV35, HPV39, HPV51, HPV56, and HPV59 in type- and gene-specific real-time multiplex PCR assays. Specimens were also tested for the presence of L1 sequences using two versions of the Roche Linear Array genotyping assay. Measures of concordance of a modified version of the Linear Array and the standard Linear Array PCR assay were evaluated. With specimen DNA extraction using the Qiagen Spin blood kit held as the constant, multiplex PCR assays detect more HPV-positive specimens for the 14 HPV types common to both than either version of the Linear Array HPV genotyping assay. Type-specific agreements between the assays were good, at least 0.838, but were often driven by negative agreement in HPV types with low prevalence, as evidenced by reduced proportions of positive agreement. Overall HPV status agreements ranged from 0.615 for multiplex PCR and standard Linear Array to 0.881 for multiplex PCR and modified Linear Array. An alternate DNA extraction technique, that used by the Qiagen MinElute kit, impacted subsequent HPV detection in both the multiplex PCR and Linear Array assays.

Human papillomavirus (HPV) DNA triage of women with atypical squamous cells of undetermined significance with Amplicor HPV and Hybrid Capture 2 assays for detection of high-grade lesions of the uterine cervix

Up to 20% of women having a cytology smear showing atypical squamous cells of undetermined significance (ASC-US) and infected with high-risk human papillomavirus (HR HPV) have high-grade cervical intraepithelial neoplasia (CIN 2/3). Results obtained with the Amplicor HPV and Hybrid Capture 2 (HC-2) assays for HR HPV DNA detection in women referred to colposcopy for an ASC-US smear were compared. Cervical samples in PreservCyt were tested for the presence of 13 HR HPV types with HC-2, with Amplicor at three cutoffs for positivity (0.2, 1.0, and 1.5 optical density units), and for 36 genotypes with the Linear Array (LA). Of 396 eligible women, 316 did not have CIN, 47 had CIN 1, 29 had CIN 2/3, and 4 had CIN of unknown grade. HR HPV was detected in 129 (32.6%) and 164 (41.4%) samples with HC-2 and Amplicor HPV (cutoff, 0.2), respectively (P = 0.01). Overall, 112 specimens were positive and 215 were negative with the HC-2 and Amplicor HPV assays (agreement of 82.6%; 95% confidence interval [CI], 78.5 to 86.0). The clinical sensitivity and specificity of Amplicor HPV at cutoffs of 0.2, 1.0 and 1.5 and of HC-2 for detection of CIN 2/3 were 89.7% (95% CI, 72.8 to 97.2) and 62.5% (95% CI, 57.5 to 52.4), 89.7% (95% CI, 72.8 to 97.2) and 64.5% (95% CI, 59.4 to 69.2), 89.7% (95% CI, 72.8 to 97.2) and 64.7% (95% CI, 59.7 to 69.5), and 93.1% (95% CI, 77.0 to 99.2) and 72.2% (95% CI, 67.4 to 76.5), respectively. Both HR HPV detection tests identified women with ASC-US who would benefit the most from colposcopy. Women with persistent HR HPV infection need further investigation despite a first normal colposcopy.

Cervical nitric oxide release and persistence of high-risk human papillomavirus in women

Nitric oxide may serve as one cofactor for human papillomavirus (HPV)-induced development of cervical cancer. Therefore, we first assessed the levels of cervical fluid nitric oxide metabolite (NOx) in 283 women with and without high-risk (hr) HPV. The NOx level in women with hr HPV (48.4 μmol/L [95% CI: 39.4-56.6], n = 199) was higher (p < 0.001) than that in women without hr HPV (24.6 μmol/L [95% CI: 19.1-38.7], n = 84). Second, we evaluated if cervical fluid NOx levels could predict the persistence of hr HPV. Therefore, we followed up 113 women with detectable hr HPV without any treatment for 12 mo and repeated hr HPV test. High-risk HPV persisted in 72 women (64%) and disappeared in 41 women (36%). The median basal levels of NOx were higher (p = 0.02) in women with persistent hr HPV (56.9 μmol/L [95% CI: 48.7-81.0]) compared to those with eradicated hr HPV (37.7 μmol/L [95% CI: 27.0-58.0]). The NOx level higher than the 75th percentile (>87.0 μmol/L) predicted hr HPV persistence (OR = 4.1 [95% CI: 1.3-13.1]). This cutoff level of NOx showed 33% sensitivity and 90% specificity in predicting the persistence of hr HPV, but it failed to predict cytological progression or regression in 12 mo. In conclusion, high cervical fluid NOx appears to be connected to the persistence of hr HPV, but the low predictive capacity of NOx prevents its clinical use at this phase.

Is HPV-DNA testing a useful tool in predicting low-grade squamous intraepithelial lesion outcome? A retrospective longitudinal study

HPV-DNA testing has entered in clinical practice. Three important questions remain controversial: 1) which is the best HPV-DNA technology? 2) Which age group should be targeted? 3) Is HPV-DNA testing predictive of disease outcome? The answers to these queries represent the endpoints of this study. The population of this retrospective study consisted of 272 women, each one having: baseline cytological diagnosis of Low-grade Squamous Intraepithelial Lesion (LSIL); baseline HPV-DNA reports by Hybrid Capture 2 (HC2) and MY09/11 consensus primers PCR; follow-up duration over 3-years; cytological report of disease status at follow-up time. Firstly, we assessed the concordance and the performances of both HPV-DNA testing, then we correlated, respectively HPV-DNA results and age of patients to disease outcome. DNA testing methods agreed in 83.4 percent of cases (K=0.66). Baseline HPV-DNA result was not significantly associated to disease outcome (p=0.06). Within HPV-DNA positive group, we found no evidence of correlation between age and LSIL prognosis (p=0.89). Confining the analysis to age-stratified HPV-DNA negative women, the differences were statistically significant (p=0.01). In conclusion, HPVDNA testing gives no information about the real behaviour of cervical abnormalities. These findings suggest the demand for additive markers, reflecting the risk of progression, in prevention strategy and clinical approach.

Detection of HPV-DNA by a PCR-based method in formalin-fixed, paraffin-embedded tissue from rare endocervical carcinoma types

High-risk human papilloma virus (HPV) seems to play a role in the pathogenesis of cervical squamous neoplasia and adenocarcinomas of the mucinous and endometrioid cell types. Cervical serous, clear cell, and small cell carcinomas differ from the conventional endocervical adenocarcinoma in their clinical characteristics. The data on the role of HPV in their pathogenesis are limited. In this study, we examined the presence of high-risk HPV-DNA in rare types of cervical carcinoma using polymerase chain reaction-based test. In-house cervical serous, clear cell, and small cell carcinoma cases accessioned between 2000 and 2008 were tested for HPV by polymerase chain reaction amplification of DNA extracted from deparaffinized sections using Roche AMPLICOR HPV Amplification Detection and Control Kits. The kit detects all 13 high-risk HPV-DNA genotypes. The positive cut-off point for AMPLICOR HPV Test was A450 = 0.2. We identified 4 serous, 3 clear cell, 1 mixed clear cell and serous, and 5 small cell carcinomas. High-risk HPV-DNA tested positive in 3 out of 4 serous carcinomas, 2 out of 3 cervical clear cell carcinomas, and all 5 cases of small cell carcinoma and the mixed cell type. Our report documents HPV status in a series of archival unusual types of adenocarcinoma of the uterine cervix. It suggests a robust association between high-risk HPV and these rare subtypes. Despite their unique clinical setting and morphologic appearance, the majority of these tumors likely share a common HPV-mediated carcinogenic pathway. Our observation is particularly significant in cervical cancer prevention as we enter the HPV vaccination era.

Recovery of DNA from BD SurePath cytology specimens and compatibility with the Roche AMPLICOR Human Papillomavirus (HPV) Test

BACKGROUND

The AMPLICOR HPV Test has been validated for use with cervical cells collected in liquid-based preservative fluids, such as BD SurePath. It is currently recommended, however, that residual BD SurePath samples be stored at 4 degrees C prior to testing.

OBJECTIVES

The aim of this study was to demonstrate that DNA isolated from SurePath cervical cytology specimens and stored at ambient temperature was also compatible with the AMPLICOR HPV Test.

STUDY DESIGN

DNA was extracted using the AmpliLute Media Sample Preparation Kit. Amplification and detection of HPV was performed both as directed by the manufacturer and with minor protocol modifications.

RESULTS

Cervical specimens collected in SurePath preservative fluid remained stable for testing with the AMPLICOR HPV Test for at least 21 days. The performance of DNA extracted from specimens stored at room temperature was equivalent to DNA extracted from specimens stored at 4 degrees C. The beta-globin internal control was detected in all of the 146 residual SurePath cervical cytology specimens tested using the AMPLICOR HPV Test, and high-risk HPV was detected in 46.2% (18/39) of ASCUS cases, in 63.3% (19/30) of LSIL cytology specimens, and 92.3% (24/26) of HSIL cases. Concordance of AMPLICOR HPV Test results with Hybrid Capture II was 83.9%.

CONCLUSIONS

The AMPLICOR HPV Test can be successfully and reproducibly performed from DNA isolated from residual SurePath cervical cytology specimens stored at ambient temperature for at least 21 days. This provides clinical laboratories flexible storage conditions for residual SurePath cytology specimens.

Comparison of the clinical performance of carcinogenic HPV typing of the Linear Array and Papillocheck HPV-screening assay

BACKGROUND

HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 66 are considered carcinogenic for human beings. DNA-chip technology, Papillocheck HPV-screening (Greiner) and reverse dot blot, Linear Array (LA) (Roche) are tools to assess the distribution of HPV genotypes.

OBJECTIVES

The aim of the study was to compare the clinical performance of Papillocheck and LA assays using a clinical cut-off of CIN2+. The secondary aim was to comparatively assess the distribution of HPV types using these two assays.

STUDY DESIGN

The study population comprised 239 women referred for colposcopy and histology. Papillocheck, LA, and Hybrid Capture II (HCII) tests were done on all samples.

RESULTS

All tests showed good sensitivity and NPV (greater than 90%). None of the comparisons of sensitivities, specificities, PPVs, and NPVs showed statistically relevant differences between tests. High-risk HPV positivity rate was similar for all tests (Papillocheck 75%, LA 77%, and HCII 73%). Agreement between tests was good. The concordance levels between HCII and Papillocheck and between HCII and LA were 93% (k=0.82) and 92% (k=0.80), respectively. Papillocheck and LA tests showed a high overall concordance rate of 96% (k=0.90). HPV16 was the most detected type (45% with Papillocheck, and 47% with LA), and HPV31 was the second most detected type (13% with Papillocheck, and 14% with LA).

CONCLUSIONS

The Papillocheck HPV-screening test and LA test have a good clinical sensitivity to detect HPV types in CIN2+ patients. These assays allow, in the same experiment, to detect and determine the virus type. Our study showed that HPV types 16 and 31/33 are the most prevalent.

Direct visual detection of DNA based on the light scattering of silica nanoparticles on a human papillomavirus DNA chip

A detection system for a human papillomavirus (HPV) DNA chip based on the light scattering of aggregated silica nanoparticle probes is presented. In the assay, a target HPV DNA is sandwiched between the capture DNA immobilized on the chip and the probe DNA immobilized on the plain silica nanoparticle. The spot where the sandwich reaction occurs appears bright white and is readily distinguishable to the naked eye. Scanning electron microscopy images clearly show the aggregation of the silica nanoparticle probes. When three different sized (55 nm, 137 nm, 286 nm) plain silica nanoparticles were compared, probes of the larger silica nanoparticles showed a higher scattering intensity. Using 286-nm silica nanoparticles, the spots obtained with 200 pM of target DNA were visually detectable. The demonstrated capability to detect a disease related target DNA with direct visualization without using a complex detection instrument provides the prerequisite for the development of portable testing kits for genotyping.

Comparison of the novel human papillomavirus 4 auto-capillary electrophoresis test with the hybrid capture 2 assay and with the PCR HPV typing set test in the detection of high-risk HPV including HPV 16 and 18 genotypes in cervical specimens

The aim of this study was to compare the novel human papillomavirus (HPV) detection method, the HPV 4 Auto-capillary Electrophoresis (ACE) test with the hybrid capture (HC) 2 assay for the detection of high-risk HPVs. In addition, we compared the HPV 4 ACE test with the polymerase chain reaction HPV Typing Set test for the detection of HPV 16 and HPV 18 genotypes. One hundred ninety-nine cervical swab samples obtained from women with previous abnormal Pap smears were subjected to testing with the three HPV tests. The HPV 4 ACE test and the HC 2 assay showed substantial agreement for detection of high-risk HPVs (85.4%, kappa=0.71). The HPV 4 ACE test also showed substantial agreement with the PCR HPV Typing Set test in the detection of HPV 16 and HP V 18 genotypes (89.9%, kappa=0.65). In correlation with cytologic results, the sensitivities and specificities of the HPV 4 ACE test and HC 2 assay were 92.9% vs. 92.9% and 48.1% vs. 50.8%, respectively, when high-grade squamous intraepithelial lesions were regarded as abnormal cytologies. The novel HPV 4 ACE test is a valuable tool for the detection of high-risk HPVs and for genotyping of HPV 16 and HPV 18.

Mannose-binding lectin in high-risk human papillomavirus infection

OBJECTIVE

Mannose-binding lectin (MBL) is a serum lectin that mediates phagocytosis and activates complement. We investigated the association of mbl-2 functional polymorphisms with human papillomavirus (HPV) infection, which is a primary etiologic factor for cervical cancer.

STUDY DESIGN

The frequencies of haplotypes and genotypes of mbl-2 exon1 and promoter region variants were analyzed in 150 patients with HPV and 277 control subjects with no HPV. Unconditional logistic regression analysis was performed to evaluate an association between specific mbl-2 alleles and susceptibility to HPV infection.

RESULTS

The frequency of high-producer mbl-2 genotypes was higher in patients with HPV than in control subjects with no HPV (P = .001). The genotype of the mbl-2 gene polymorphisms represented the least significant risk for the group with HPV.

CONCLUSION

Certain polymorphisms in the MBL promoter region are increased among cervical samples that demonstrate HPV infection. This finding suggests a potential link between MBL and high-risk HPV infection.