Cervista HR and HPV 16/18 assays vs hybrid capture 2 assay: outcome comparison in women with negative cervical cytology

Advanced technologies towards improved HPV diagnostics

Persistent infection with high-risk types of human papillomaviruses (HPV) is a major cause of cervical cancer, and an important factor in other malignancies, for example, head and neck cancer. Despite recent progress in screening and vaccination, the incidence and mortality are still relatively high, especially in low-income countries. The mortality and financial burden associated with the treatment could be decreased if a simple, rapid, and inexpensive technology for HPV testing becomes available, targeting individuals for further monitoring with increased risk of developing cancer. Commercial HPV tests available in the market are often relatively expensive, time-consuming, and require sophisticated instrumentation, which limits their more widespread utilization. To address these challenges, novel technologies are being implemented also for HPV diagnostics that include for example, isothermal amplification techniques, lateral flow assays, CRISPR-Cas-based systems, as well as microfluidics, paperfluidics and lab-on-a-chip devices, ideal for point-of-care testing in decentralized settings. In this review, we first evaluate current commercial HPV tests, followed by a description of advanced technologies, explanation of their principles, critical evaluation of their strengths and weaknesses, and suggestions for their possible implementation into medical diagnostics.

Molecular diagnostics of infectious disease: Detection and characterization of microbial agents in cytology samples

BACKGROUND

Cytology samples are widely used to diagnose various infectious diseases by detection and identification of causative infectious agents, including bacteria, fungi, and viruses. The role of cytopathology in infectious disease has expanded tremendously in the past decades with the advances in molecular techniques. Molecular diagnostic methods, compared to conventional methods, have shown improved patient outcome, reduction in cost, and shortened hospital stay times. The aim of this article is to review molecular testing in cytology samples for diagnosis of infectious diseases.

METHODS

The literature search for molecular testing in common cytology samples for diagnosis of infectious diseases was performed. The findings of the studies were summarized. The common cytology samples included in this article were gynecologic specimens, cerebrospinal fluid, bronchoalveolar lavage, and urine samples.

CONCLUSIONS

There are a number of molecular diagnostic tests that are available to be used in common cytology samples to detect infectious agents. Each test has its own advantages and limitations. It is our hope that upon reading this review article, the readers will have better understanding of molecular diagnostic testing of infectious diseases utilizing commonly sampled cytology specimens in daily practice.

Molecular and immunophenotypic characterization of anal squamous cell carcinoma reveals distinct clinicopathologic groups associated with HPV and TP53 mutation status

Squamous cell carcinoma (SqCC) is the most common malignancy of the anal canal, where it is strongly associated with HPV infection. Characteristic genomic alterations have been identified in anal SqCC, but their clinical significance and correlation with HPV status, pathologic features, and immunohistochemical markers are not well established. We examined the molecular and clinicopathologic features of 96 HPV-positive and 20 HPV-negative anal SqCC. HPV types included 89 with HPV16, 2 combined HPV16/HPV18, and 5 HPV33. HPV-positive cases demonstrated frequent mutations or amplifications in PIK3CA (30%; p = 0.027) or FBXW7 mutations (10%). HPV-negativity was associated with frequent TP53 (53%; p = 0.00001) and CDKN2A (21%; p = 0.0045) mutations. P16 immunohistochemistry was positive in all HPV-positive cases and 3/20 HPV-negative cases (p < 0.0001; sensitivity: 100%; specificity: 85%) and was associated with basaloid morphology (p = 0.0031). Aberrant p53 immunohistochemical staining was 100% sensitive and specific for TP53 mutation (p < 0.0001). By the Kaplan-Meier method, HPV-negativity, aberrant p53 staining, and TP53 mutation were associated with inferior overall survival (OS) (p < 0.0001, p = 0.0103, p = 0.0103, respectively) and inferior recurrence-free survival (p = 0.133, p = 0.0064, and p = 0.0064, respectively). TP53/p53 status stratified survival probability by HPV status (p = 0.013), with HPV-negative/aberrant p53 staining associated with the worst OS, HPV-positive/wild-type p53 with best OS, and HPV-positive/aberrant p53 or HPV-negative/wild-type p53 with intermediate OS. On multivariate analysis HPV status (p = 0.0063), patient age (p = 0.0054), T stage (p = 0.039), and lymph node involvement (p = 0.044) were independently associated with OS. PD-L1 expression (CPS ≥ 1) was seen in 30% of HPV-positive and 40% of HPV-negative cases, and PD-L1 positivity was associated with a trend toward inferior OS within the HPV-negative group (p = 0.064). Our findings suggest that anal SqCC can be subclassified into clinically, pathologically, and molecularly distinct groups based on HPV and TP53 mutation status, and p16 and p53 immunohistochemistry represent a clinically useful method of predicting these prognostic groups.

High-Risk Human Papillomavirus Identification in Precancerous Cervical Intraepithelial Lesions

OBJECTIVE

This review aims to summarize the currently available human papillomavirus (HPV) testing methods for precancerous cervical intraepithelial lesions.

MATERIALS AND METHODS

A literature search of PubMed using key words "high-risk HPV, precancerous cervical intraepithelial lesions, FDA-approved HPV tests, p16 IHC, Ki 67 IHC, fluorescent in situ hybridization for HPV, Pap smear, HPV vaccines, HPV tests using self-collected samples, and next-generation sequencing" was performed between January 1 and June 14, 2019. The package inserts of the Food and Drug Administration-approved HPV tests were obtained from the companies' Web sites.

RESULTS

Multiple morphology-based, immunohistochemical staining and nucleic acid HPV tests were reviewed, including the material required, methodologies, result interpretations, as well as their advantages, limitations, and futures. The structure of HPV and its natural history of infection and transmission were touched on as well for a better understanding of these testing methods.

CONCLUSIONS

Human papillomavirus tests are a critical component for cervical cancer screening, and understanding of these tests helps test results interpretation and patients' triage.

Association of cervical microbial community with persistence, clearance and negativity of Human Papillomavirus in Korean women: a longitudinal study

The present study aimed to identify the cervical microbes that are associated with HPV negativity, HPV clearance and HPV persistence and to assess the microbes’ longitudinal associations as related to HPV infection dynamics among Korean women. We enrolled 41 women with 107 samples, and classified them according to the HPV infection dynamics: HPV negativity (21 samples, 10 subjects), HPV clearance (42 samples, 15 subjects), and HPV persistence (44 samples, 16 subjects). Cervical swabs were collected at the baseline and six-month-interval follow-up visits. HPV positivity was determined by HPV DNA HC2 assay, and the microbiome was analyzed using 16SrRNA pyrosequencing, linear discriminant analysis effect size and multivariate logistic analysis. In the multivariate logistic analysis results, Lactobacillus crispatus (multivariate OR (mOR) = 8.25, 95% CI 2.13~32.0) was predominant in the HPV-negative group. We observed that Eubacterium eligens (mOR = 11.5, 95% CI 1.31~101.4), Gardnerella vaginalis (mOR = 17.0, 95% CI 2.18–131.8), and Ureaplasma urealyticum (mOR = 7.42, 95% CI 1.3–42.46) had the strongest associations with HPV clearance, and Lactobacillus johnsonii (mOR = 16.4, 95% CI 1.77–152.2) with HPV persistence. Overall, greater diversity was observed in HPV-persistence than in HPV-negative women. Our findings suggest that the presence and prevalence of a specific cervical microbiome are factors involved in HPV dynamics.

Comparison of the Cepheid Xpert HPV test and the HC2 High-Risk HPV DNA Test for detection of high-risk HPV infection in cervical smear samples in SurePath preservative fluid

Purpose. Cytological and histological cervical screening methods for human papillomavirus may be subjective. Current guidelines recommend the use of direct human papillomavirus screening by molecular methods in conjunction with cytology for the detection of high-risk human papillomavirus types with carcinogenic potential. In this study, we compared the performance of the molecular Cepheid Xpert HPV test to the FDA-approved HC2 High-Risk HPV DNA Test on samples from patients presenting for cervical screening, regardless of the cytology results, in which cervical cell samples were originally collected for Papanicolaou (Pap) smear specimens in Becton Dickinson (BD) SurePath preservative fluid.Methodology. Cervical cells were obtained for Pap smear specimens from 343 women attending Qatif Central Hospital in Saudi Arabia for cervical cancer screening using a Cytobrush Plus GT and immersed in BD SurePath preservative fluid in BD SurePath collection vials. The study was carried out between December 2015 and July 2016.Results. The Xpert HPV test was positive in 27 (7.9 %) of the samples. The HC2 High-Risk HPV DNA Test was positive in 32 (9.3 %) of the samples. The most common HPV types according to the Xpert HPV test were HPV other types, either alone (n=15) or in combination with HPV16 (n=3). The overall concordance rate between the tests was 98.5 %. The positive concordance was 84.4 %.Conclusion. The Xpert HPV test is convenient to use on cervical cell samples collected for Pap smear specimens in BD SurePath preservative fluid within an hour and is a viable alternative to the HC2 High-Risk HPV DNA Test for HPV testing.

A seminested PCR assay for detection and typing of human papillomavirus based on E1 gene sequences

HPV infection is considered one of the leading causes of cervical cancer in the world. To date, more than 180 types of HPV have been described and viral typing is critical for defining the prognosis of cancer. In this work, a seminested PCR which allow fast and inexpensively detection and typing of HPV is presented. The system is based on the amplification of a variable length region within the viral gene E1, using three primers that potentially anneal in all HPV genomes. The amplicons produced in the first step can be identified by high resolution electrophoresis or direct sequencing. The seminested step includes nine specific primers which can be used in multiplex or individual reactions to discriminate the main types of HPV by amplicon size differentiation using agarose electrophoresis, reducing the time spent and cost per analysis.

Human Papillomavirus Laboratory Testing: the Changing Paradigm

High-risk human papillomaviruses (HPVs) cause essentially all cervical cancers, most anal and oropharyngeal cancers, and some vaginal, vulvar, and penile cancers. Improved understanding of the pathogenesis of infection and the availability of newer tests are changing the approach to screening and diagnosis. Molecular tests to detect DNA from the most common high-risk HPVs are FDA approved for use in conjunction with cytology in cervical cancer screening programs. More-specific tests that detect RNA from high-risk HPV types are now also available. The use of molecular tests as the primary screening tests is being adopted in some areas. Genotyping to identify HPV16 and -18 has a recommended role in triaging patients for colposcopy who are high-risk HPV positive but have normal cytology. There are currently no recommended screening methods for anal, vulvar, vaginal, penile, or oropharyngeal HPV infections. HPV testing has limited utility in patients at high risk for anal cancer, but p16 immunohistochemistry is recommended to clarify lesions in tissue biopsy specimens that show moderate dysplasia or precancer mimics. HPV testing is recommended for oropharyngeal squamous cell tumors as a prognostic indicator. Ongoing research will help to improve the content of future guidelines for screening and diagnostic testing.

A population-based observational study comparing Cervista and Hybrid Capture 2 methods: improved relative specificity of the Cervista assay by increasing its cut-off

BACKGROUND

High-risk human papillomavirus (HR HPV) testing has been shown to be a valuable tool in cervical cancer screening for the detection of cervical pre-cancer and cancer.

METHODS

We report a purely observational study evaluating HR HPV prevalences in residual liquid-based cytology (LBC) samples using both the Cervista™ HPV HR Test and the Digene Hybrid Capture 2 High-Risk HPV DNA Test (HC2) in a sample of 1,741 women aged ≥30 years of a German routine screening population of 13,372 women. Test characteristics were calculated and a novel method for measuring test performances was applied by calculating ratios of sensitivity or specificity.

RESULTS

The overall agreement of both tests for detection of HR HPV was excellent (κ = 0.8). Relative sensitivities for the detection of histologically confirmed severe cervical intraepithelial dysplasia (CIN3+) were similar for both HPV-tests, which was confirmed by the ratio analysis. However, discrepancy analysis between the Cervista HPV HR test and HC2 revealed a high false positive rate of the Cervista HPV HR test in the cytology normal category.

CONCLUSIONS

Performance of the Cervista HPV test in cervical specimens with abnormal cytology is comparable to HC2 as both tests were highly sensitive and specific for the detection of high grade cervical disease. We also demonstrate evidence that modification of the cut-off values drastically reduces the false positive rate in the cytology normal category without affecting the detection of CIN3+, which ultimately improved specificity of the Cervista HPV HR assay.

Clinical validation of the Cervista HPV HR test according to the international guidelines for human papillomavirus test requirements for cervical cancer screening

This study demonstrates that both the clinical sensitivity and specificity of the Cervista HPV HR test for high-risk human papillomavirus (HPV) detection are not inferior to those of the Hybrid Capture 2 (HC2) test. The intra- and interlaboratory reproducibilities of Cervista were 92.0% (kappa, 0.83) and 90.4% (kappa, 0.80), respectively. The Cervista HPV HR test fulfills all the international HPV test requirements for cervical primary screening purposes.

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.

Comparing the Cervista HPV HR test and Hybrid Capture 2 assay in a Dutch screening population: improved specificity of the Cervista HPV HR test by changing the cut-off

The diagnostic performance of the widely-used Cervista HPV HR test was compared to the Hybrid Capture 2 (HC2) test in a Dutch population-based cervical cancer screening program. In 900 scrapings of women with normal cytomorphology, specificity was 90% (95%CI: 87.84–91.87) for the Cervista HPV HR test and 96% (95%CI: 94.76–97.37) for the HC2 test with 93% agreement between both tests (κ = 0.5, p<0.001). The sensitivity for CIN2+ using 65 scrapings of women with histological-confirmed CIN2+ was 91% (95%CI: 80.97–96.51) for the Cervista HPV HR test and 92% (95%CI: 82.94–97.43) for the HC2 test with 95% agreement between both tests (κ = 0.7, p<0.001). Fifty-seven of 60 HC2 negative/Cervista positive cases tested HPV-negative with PCR-based HPV assays; of these cases 56% were defined as Cervista triple-positive with FOZ values in all 3 mixes higher than the second cut-off of 1.93 (as set by manufacturer). By setting this cut-off at 5.0, specificity improved significantly without affecting sensitivity. External validation of this new cut-off at 5.0 in triple-positive scrapings of women selected from the SHENCCASTII database revealed that 22/24 histological normal cases now tested HPV-negative in the Cervista HPV HR test, while CIN2+ lesions remained HPV-positive. The intra-laboratory reproducibility of the Cervista HPV HR test (n = 510) showed a concordance of 92% and 93% for cut-off 1.93 and 5.0 (κ = 0.83 and κ = 0.84, p<0.001) and inter-laboratory agreement of the Cervista HPV HR test was 90% and 93% for cut-off 1.93 and 5.0 (κ = 0.80 and κ = 0.85, p<0.001). In conclusion, the specificity of the Cervista HPV HR test could be improved significantly by increasing the second cut-off from 1.93 to 5.0, without affecting the sensitivity of the test in a population-based screening setting.

Clinical prediction based on HPV DNA testing by hybrid capture 2 (HC2) in combination with liquid-based cytology (LBC)

Primary screening by HPV DNA testing is an effective method for reducing cervical cancer and has proven more sensitive than cytology. To advance this approach, many molecular methods have been developed. Hybrid capture 2 provides semi-quantitative results in ratios of relative light units and positive cutoff values (RLU/ PC). Twenty-five thousand and five patients were included in this study to analyze the correlation between the ratio of RLU/PC and stage of cervical dysplasia. The results show that the RLU/PC ratios ranged from 0-3500 while almost normal cases, ASC-US and ASC-H, had values below 200. Of those samples negative for cytology markers, 94.6% were normal and their RLU/PC ratios were less than 4. With an RLU/PC ratio greater than 4 and less than or equal to 300, the percentages in all age groups were normal 53.6%, LSIL 20.2%, ASC-US 17.2%, HSIL 6.13%, ASC-H 2.72%, and AGC 0.11%, respectively. In contrast, 64.0% of samples with a RLU/ PC ratio greater than 300 and less than or equal to 3500 were LSIL. These results should contribute to cost effective cervical cancer management strategies. Further studies of associations with particular HPV genotypes would be useful to predict the risk of progression to cancer.

Prevent cervical cancer by screening with reliable human papillomavirus detection and genotyping

The incidence of cervical cancer is expected to rise sharply in China. A reliable routine human papillomavirus (HPV) detection and genotyping test to be supplemented by the limited Papanicolaou cytology facilities is urgently needed to help identify the patients with cervical precancer for preventive interventions. To this end, we evaluated a nested polymerase chain reaction (PCR) protocol for detection of HPV L1 gene DNA in cervicovaginal cells. The PCR amplicons were genotyped by direct DNA sequencing. In parallel, split samples were subjected to a Digene HC2 HPV test which has been widely used for "cervical cancer risk" screen. Of the 1826 specimens, 1655 contained sufficient materials for analysis and 657 were truly negative. PCR/DNA sequencing showed 674 infected by a single high-risk HPV, 188 by a single low-risk HPV, and 136 by multiple HPV genotypes with up to five HPV genotypes in one specimen. In comparison, the HC2 test classified 713 specimens as infected by high-risk HPV, and 942 as negative for HPV infections. The high-risk HC2 test correctly detected 388 (57.6%) of the 674 high-risk HPV isolates in clinical specimens, mislabeled 88 (46.8%) of the 188 low-risk HPV isolates as high-risk genotypes, and classified 180 (27.4%) of the 657 "true-negative" samples as being infected by high-risk HPV. It was found to cross-react with 20 low-risk HPV genotypes. We conclude that nested PCR detection of HPV followed by short target DNA sequencing can be used for screening and genotyping to formulate a paradigm in clinical management of HPV-related disorders in a rapidly developing economy.