Laboratory and clinical aspects of human papillomavirus testing

Human Papilloma Virus DNA Detection in Clinical Samples Using Fluorogenic Probes Based on Oligonucleotide Gated Nanoporous Anodic Alumina Films

In this work, fluorogenic probes based on oligonucleotide capped nanoporous anodic alumina films are developed for specific and sensitive detection of human papilloma virus (HPV) DNA. The probe consists of anodic alumina nanoporous films loaded with the fluorophore rhodamine B (RhB) and capped with oligonucleotides bearing specific base sequences complementary to genetic material of different high-risk (hr) HPV types. Synthesis protocol is optimized for scale up production of sensors with high reproducibility. The sensors' surfaces are characterized by scanning electron microscopy (HR-FESEM) and atomic force microscopy (AFM) and their atomic composition is determined by energy dispersive X-ray spectroscopy (EDXS). Oligonucleotide molecules onto nanoporous films block the pores and avoid diffusion of RhB to the liquid phase. Pore opening is produced when specific DNA of HPV is present in the medium, resulting in RhB delivery, that is detected by fluorescence measurements. The sensing assay is optimized for reliable fluorescence signal reading. Nine different sensors are synthesized for specific detection of 14 different hr-HPV types in clinical samples with very high sensitivity (100%) and high selectivity (93-100%), allowing rapid screening of virus infections with very high negative predictive values (100%).

CIN grades possessing different HPV RNA location patterns and RNAscope is helpful tool for distinguishing squamous intraepithelial lesions in difficult cervical cases

BACKGROUND AND OBJECTIVES

The precise grading and characterization of cervical intraepithelial neoplasia (CIN) has been the focus of pathologists for a long time. This study aimed to explore known strategies for the grading of CINs.

METHODS

After routine H&E review, 85 lesions graded CIN 1, 2, or 3 were investigated primarily by HPV RNAscope to detect HR-HPV and LR-HPV, in combination with an HPV-DNA test and P16/Ki67 immunohistochemistry (IHC). Then, the 85 cases were divided into a control group (49 cases) and a test group (36 cases). The former consisted of cases with consistency between morphology, HPV DNA detection and P16/Ki67 IHC. We used them to evaluate HPV RNA distribution patterns in CINs of different grades. The latter were ambiguous cases in which pathologists could not confirm the diagnosis because of inconsistencies between morphology, HPV DNA detection and P16/Ki67 IHC. We reassessed them by comparison to the pattern in the control group.

RESULTS

The expression patterns of HPV mRNA signals were different in different CIN lesions. LSIL/CIN1 lesions were mostly expressed in superficial epithelium with diffuse clustered nuclear or cytoplasmic staining; HSIL/CIN2 were characterised by nuclear/cytoplasmic punctate or diffuse cluster nuclear staining in the mid-surface layer, and scattered nuclear/cytoplasmic punctate staining in basal and parabasal cells; whereas HSIL/CIN3 showed full-thickness nucleus/cytoplasmic scattered staining with a punctate pattern. According to the staining pattern, we corrected the diagnosis of 22 cases (22/36, 61.1%).

CONCLUSION

Because of its distinct location pattern, HPV RNAscope has obvious advantages over the HPV-DNA test, and combined with P16/Ki67 IHC, it can help pathologists correctly grade CIN. In addition, it can effectively discriminate true CIN from normal or CIN mimic lesions, such as immature squamous metaplasia, atrophy, and inflammatory/reactive changes. Therefore, HPV RNAscope is a valuable auxiliary diagnostic test to avoid the overtreatment and undertreatment of CIN lesions.

siRNA-E6 sensitizes HPV-16-related cervical cancer through Oxaliplatin: an in vitro study on anti-cancer combination therapy

BACKGROUND

Persistent infection with high-risk Human papillomaviruses (HPV), such as hr-HPV-16 and hr-HPV-18, lead to cervical cancer, the fourth most common cancer in the world. In the present study, we investigated the alteration of E6 oncogene expression by E6-specific short interfering RNA (siRNA) combined with Oxaliplatin.

METHODS

The cervical cancer cell line, CaSki, was transfected with E6-siRNA, then treated with Oxaliplatin. The cellular genes, such as p53, MMP9, Nanog, and caspases expression, were assessed by quantitative real-time PCR. The cell death rate, cell cycle, and cell viability were assessed by Annexin V/PI staining, DAPI staining, and MTT test, respectively. Furthermore, colony formation assay and scratch test determined the stemness ability and cell metastasis, respectively.

RESULTS

Combination therapy increased the re-expression of genes involved in the p53-dependent apoptosis pathway (increase in apoptosis to 44.2%), and reduced stemness and metastasis ability compared to either siRNA or Oxaliplatin monotherapy. Together, our results demonstrate that E6-siRNA and Oxaliplatin combination increased the cervical cancer cells' sensitivity to Oxaliplatin and decreased the survival rate, proliferation, and metastasis, and consequently escalated apoptosis rate, induced cell cycle arrest in the sub-G1 stage, and reduced the chemotherapy drug dosage.

CONCLUSION

Inhibition of E6 oncogene expression and subsequent E6-siRNA with Oxaliplatin combination therapy could be a novel strategy for cervical cancer treatment.

Impact of high-risk Human Papillomavirus genotyping in cervical disease in the Northern region of Portugal: Real-world data from regional cervical cancer screening program

Cervical cancer prevention is based on primary prevention with vaccines against Human Papillomavirus (HPV) and secondary prevention by screening with High-Risk-HPV (Hr-HPV) detection. Since 2017, cervical cancer screening in women aged 25-60 years has been performed in Portugal using Hr-HPV detection, followed by cytology in Hr-HPV-positive cases. Herein we report the prevalence of Hr-HPV genotypes and cytological abnormalities among 462 401 women (mean age: 43.73 ± 10.79; median age: 45; range: 24-66 years) that participated in the Regional Cervical Cancer Screening Program of the Northern Region of Portugal, performed between August 2016 and December 2021. Overall, we describe a prevalence rate of 12.50% for Hr-HPV varying from 20.76% at age 25% to 8.32% at age 64. The five most common Hr-HPV genotypes identified were HPV-68 (16.09%), HPV-31 (15.30%), HPV-51 (12.96%), HPV-16 (11.06%), and HPV-39 (11.01%). The prevalence of Hr-HPV included in the nonavalent vaccine (HPV-9valent) was 55.00% ranging from 47.78% to 59.18% across different age groups. Considering positive Hr-HPV cases, 65.68% had a Negative for Intraepithelial Lesion or Malignancy (NILM) cytology, 20.83% atypical squamous cells of undetermined significance (ASC-US), 8.85% Low-Grade Squamous Intraepithelial Lesion (LSIL), 1.65% High-Grade Squamous Intraepithelial Lesion (HSIL), 2.85% ASC-H, 0.09% Atypical Glandular Cells, 0.02% Adenocarcinomas, and 0.02% Squamous Cell Carcinoma (SCC). Our analysis revealed that HPV-9val genotypes were responsible for 52.13% NILM, 59.21% ASC-US, 55.06% LSIL, 90.14% HSIL, 83.50% ASC-H, and 100.00% SCC. Furthermore, multiple Hr-HPV infections (risk ratio [RR] = 1.46; 95% confidence interval [CI] 1.34-1.58), HPV-16/18 (RR = 5.16; 95% CI 4.75-5.93), or HPV-9val genotypes (RR = 5.23; 95% CI 4.68-5.85) were associated with a significant risk of developing >  HSIL (p < 0.001). To date, this is the largest study on Hr-HPV genotyping in cervical cancer screening that includes data from a complete cycle of the screening program. Our findings suggest a high prevalence of HPV-9valent genotypes and a significant association with an increased risk of developing > HSIL. This constitutes important data for health authorities, which may help define the future of vaccination and cervical cancer screening strategies.

Comparative assessment of test characteristics of cervical cancer screening methods for implementation in low-resource settings

Cervical cancer disproportionately affects low-resource settings. Papanicolaou, human papillomavirus (HPV), and visual inspection of cervix with acetic acid (VIA) testing, each with different characteristics, will reduce cervical cancer burden. We conducted a critical literature review using PubMed, Cochrane, WHO, and grey literature from 1994 to 2020. We examined efficacy, harms, and comparative effectiveness of screening methods by age, human immunodeficiency virus, provider characteristics, and assessed implementation challenges in low-resource settings. Comprehensive data on utility and efficacy of screening tests indicates that each screening has strengths and shortcomings but all confer acceptable performance. HPV and VIA appear more promising. Primary HPV test-and-treat, self-testing, and co-testing have been studied but data on triage plans, cost, support system, implementation and sustainability is unclear in low-resource settings. HPV testing could help target subgroups of older or higher risk women. VIA offers local capacity-building and scalability. Quality VIA technique after HPV testing is still required to guide post-screening treatments. VIA competencies decline gradually with current standard trainings. Stationary cervicography improves VIA quality but isn't scalable. Affordable smartphones eliminate this barrier, enhance training through mentorship, and advance continuing education and peer-to-peer training. Smartphone-based VIA facilitates cervical image storage for patient education, health promotion, record-keeping, follow-up care, remote expert support, and quality control to improve VIA reliability and reproducibility and reduce mis-diagnoses and burden to health systems. Rather than ranking screening methods using test characteristics alone in study or higher-resource settings, we advocate for scalable strategies that maximize reliability and access and reduce cost and human resources.

E6-E7 based nested multiplex PCR assay for genital HPV detection and simultaneous typing of 15 high and low-risk HPV types

PURPOSE

Due to a wide range of Human Papillomavirus (HPV) types associated with genital cancers; HPV genotyping remains important for the introduction of an appropriate vaccine, disease diagnosis, follow-up and epidemiological surveys. Currently, available molecular genotyping assays are not only expensive but also requires dedicated and expensive equipment which is not feasible in the majority of low-and-middle-socioeconomic countries. The purpose of the study was to develop and evaluated a cost-effective nested-multiplex polymerase chain reaction (NM-PCR) assay for HPV genotyping.

METHODS

HPV-DNA containing plasmids and cervical scrapings from histologically confirmed cervical cancer cases were used to evaluate the NM-PCR. In the first round PCR, a set of consensus primers were used to amplify 38 mucosal HPV types. HPV Type-specific primers were used in the second-round polymerase chain reaction (PCR) to amplify 15 HPV types in three multiplex cocktails. The assay sensitivity was determined with the control panel containing one to 10¹⁰genome equivalents (GE). DNA sequencing was done to confirm the PCR results.

RESULTS

The assay was able to amplify all HPV types and detected as few as 50GE per reaction. A total of 23 endo-cervical samples obtained from healthy, HPV negative subjects and 52 histologically confirmed cervical scrapings were processed for HPV genotyping by NM-PCR. HPV DNA was detected in all histologically confirmed samples. DNA sequencing results showed complete concordance with PCR results.

CONCLUSIONS

The designed nested PCR based assay had good concordance with clinical histology and sequencing results and appears to be a promising tool for HPV genotyping especially in resource-constrained settings.

Association of human papillomavirus genotype distribution and cervical cytology: a cross-sectional study

The present study attempted to analyse human papillomavirus (HPV) genotype distribution and its association with cervical cytology results in women in western China. The present retrospective analysis was performed in 1089 female outpatients with a positive HPV test result who had undergone a cervical cytology test at the gynaecological clinic, West China Second Hospital, Sichuan University, China, between January 2014 and December 2016. Of the 1089 patients with HPV infection, multiple HPV genotypes were detected in 220 patients (20.20%). Among the 1368 HPV genotypes detected, 1145 (83.70%) were high-risk subtypes. The most common genotypes were HPV-52 (18.64%), HPV-16 (16.59%), HPV-58 (13.23%), HPV-18 (6.80%), HPV-56 (5.56%) and HPV-59 (5.56%). Cervical cytology revealed abnormal cells in 430 (39.49%) patients. The most common diagnoses were atypical squamous cells of undetermined significance (ASC-US; 236 cases, 54.88%), low-grade squamous intraepithelial lesions (LSIL; 151 cases, 35.12%), high-grade squamous intraepithelial lesions (HSIL; 63 cases, 14.65%) and atypical glandular cells (AGC; 21 cases, 4.88%). HPV-66 was significantly associated (P = 0.037) with ASC; HPV-52 and HPV-56 were significantly associated with LSIL (P = 0.009 and 0.026, respectively); HPV-16 (P < 0.001), HPV-33 (P = 0.014) and HPV-58 (P = 0.003) were significantly associated with HSIL; and HPV-16 (P = 0.005) was significantly associated with AGC. HPV-16, HPV-52 and HPV-58 are associated with different diagnoses in patients with positive cervical cytological findings.

Why Does Cancer Screening Persist Despite the Potential to Harm?

Population screening for early-stage cancer or cancer precursors began in the mid-twentieth century, with the goal of reducing suffering from cancer illness and lengthening average life by preventing cancer deaths. Since the establishment of cancer screening, concerns have emerged that it may be doing considerable harm; despite this, screening practices have remained relatively intractable. This intractability in the face of harm is the central problematic of my analysis. I reinterpret a large study of breast, cervical and prostate cancer screening completed recently by our Australian research group, working across empirical bioethics, public health and social science. I suggest three reasons why cancer screening might persist as it does, and thus reach conclusions about what might be required to make cancer screening systems more responsive to the potential for harm.

Human Papillomavirus-Associated Cancers

Human Papillomavirus (HPV) is the causative agent in the majority of anal, head and neck, oral, oropharyngeal, penile, vaginal, vulvar, and cervical cancers. Cervical cancer is the fourth most common cancer among women worldwide. Of all diagnosed human malignant neoplasms, approximately 4.5% are attributable to HPV, including cervical, anal cancers, vaginal, vulvar, penile, and oropharyngeal cancers. Over 182 HPV types have been identified and sequenced to date however, only certain types of HPV are more frequent in malignant lesions and considered to be a major risk factor in the development of some cancers. Because most HPV infections are transient, and an individual's immunocompetent may clear the infection, HPV infection has received little attention from clinicians, the general public, or policy makers. This lack of attention may underpin a deadly and increasing problem because each newly acquired infection has the potential to persist and become an incurable, lifelong affliction. In addition, no successful treatment of HPV infection currently exists despite the great strides toward understanding the mechanisms underlying HPV pathogenesis. Moreover, ample research has proven that the use of prophylactic vaccines, such as Gardasil and Cervarix, have led to documented progress in decreasing the burden of HPV infection, however not all countries introduced a government-funded National HPV Vaccination Program to protect young men and women. This chapter summarizes the HPV infection, detection and prevention. We also shed light on non-cervical HPV-related cancers, which is rapidly increasing in more developed countries toward cervical cancer.

The role of human papilloma virus test in men: First exhaustive review of literature

Human papilloma virus (HPV) infection is the most common sexually transmitted infection worldwide. There is a high detection rate in sexually active young people but the risk, in males, persists over years. Currently, the American Center for Disease Control and Prevention does not recommend the evaluation of men for HPV and, the extant bibliography, backs up this stance for several reasons. Objective of the paper was to evaluate the usefulness of HPV detection methods for men; A comprehensive and exhaustive review of the literature was performed. Many are methods for HPV detection used in cervical cancer screening as well as in the study and management of patients with cytological alterations of the lower genital tract. Need for HPV detection methods in men are numerous: screening for both partner/gender; anogenital warts; recurrent respiratory papillomatosis; HPV-related cancer in men; fertility. No HPV test for men has been approved by the FDA, nor has any test been approved for detection of the virus in areas other than the cervix. Many are methods for HPV detection that have shown their usefulness in some of the pathologies associated with male HPV but, despite this, none of them has been approved for man.

High-Risk human papillomavirus genotype distribution in the Northern region of Portugal: Data from regional cervical cancer screening program

High-Risk Human papillomavirus (HR-HPV) full genotyping methods have been described as of great potential use in epidemiology and preventive strategies, including cervical cancer screening and HPV vaccination. We characterized the prevalence and distribution of HR-HPV genotypes in cervico-vaginal samples obtained from the Regional Cervical Cancer Screening Program from the Northern Region of Portugal. HR-HPV genotyping was performed using Anyplex™ II HPV-HR Detection kit in 105,458 women enrolled between August 2016 and December 2017. HR-HPVs were detected in 10,665 women (10.2%) with a prevalence ranging from 6.2 to 17.1% depending on age, and from 8.7 to 10.7% depending on geographical location. Multiple infections with two or more HR-HPVs were detected in 2736 (25.7%) of HR-HPV women ranging from 16.5 to 31.0% depending on age. Amongst HR-HPV positive women, HPV-16 (17.5%), HPV-39 (16.7%), HPV-31 (15.0%), HPV-68 (13.2%), HPV-52 (10.7%) and HPV-51 (10.6%) were the most common genotypes in our population, being HPV-16 more frequent in women aged from 30 to 45 years and HPV-39 in 50-65 years. Results also show that HPV16/18 are present in 22.1% and HPV16/18/31/33/45/52/58 in 47.6% of HR-HPV positive women. This is the largest study on HR-HPV genotyping for Cervical Cancer Screening in European populations and provides critical data for program management and vaccine policy.

Analytical performance of a low-cost multiplex polymerase chain reaction human papillomavirus genotyping assay for use in Sub-Saharan Africa

We have tested a multiplex polymerase chain reaction (PCR) human papillomavirus (HPV) genotyping assay to fill the need for rapid and low-cost HPV detection in Sub-Saharan Africa. This method allows high throughput genotyping and simultaneous detection of 14 high-risk and two low-risk HPV types, by PCR amplification of HPV DNAs in a single reaction tube. In this study, we describe stepwise experiments to validate the multiplex HPV PCR assay for determination of HPV genotypes from 104 cervical brush samples from Tanzanian women. Assay performance was evaluated by determination of intra-laboratory reproducibility, sensitivity, and specificity. Further performance was assessed by comparison with the widely accepted and validated HPV My09/My11 amplification and hybridization assay. Statistics; the Cohen kappa (κ) and McNemar P values were used to analyze interobserver and intermethod agreement. Overall concordance between the multiplex and line blot hybridization assays was 99% (per sample) with a κ value equal to 0.95; and 96.49% (per detection event) with a κ value of 0.92. Interobserver reproducibility of the assay per sample was 95.76% with κ of 0.91. These results demonstrate that the multiplex HPV PCR assay has high analytical sensitivity and specificity in detecting as many as 16 different HPV genotypes and that its simplicity and low cost makes it well suited for sub-Saharan Africa.

Preparation and characterization of functionalized heparin-loaded poly-Ɛ-caprolactone fibrous mats to prevent infection with human papillomaviruses

In this study, heparin-loaded poly-ɛ-caprolactone (PCL) fibrous mats were prepared and characterized based on their physical, cytotoxic, thermal, and biological properties. The main objective of the work described here was to test the hypothesis that incorporation of heparin into a PCL carrier could serve as bio-compatible material capable of inhibiting Human Papillomavirus (HPV) infection. The idea of firmly anchoring heparin to capture soluble virus, vs. a slow heparin release to inhibit a virus in solution was tested. Thus, one material was produced via conventional heparin matrix encapsulation and electrohydrodynamic fiber processing in one step. A second type of material was obtained via heparin crosslinking. This was achieved by running a carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling reaction on preformed PCL fibers. In vitro HPV16 L1 protein binding capacity studies were performed. Infectivity assays were done using HPV16 pseudoviruses (PsVs) carrying a GFP plasmid to directly test the ability of the fibrous mats to prevent internalization of HPV PsVs. The crosslinked heparin material presented a dissociation constant (K_d) value comparable to those found in the literature for different heparin-protein L1 peptide interactions. Both materials significantly reduced internalization of HPV PsVs, with a reduction of 94% of PsVs internalization when matrix encapsulated heparin-loaded material was present. Differences in performance between the two proposed structures are discussed.

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.

Attitude to Human Papillomavirus Deoxyribonucleic Acid-Based Cervical Cancer Screening in Antenatal Care in Nigeria: A Qualitative Study

OBJECTIVES

Human papillomavirus (HPV) deoxyribonucleic acid (DNA)-based testing is increasingly used for cervical cancer screening in developed countries, but the best approach to utilizing it in low- and middle-income countries (LMIC) is unclear. Incorporation of HPV DNA-based testing into routine antenatal care (ANC) is a potential yet poorly explored strategy for cervical cancer screening in LMIC. We explored the attitude of health care workers and pregnant women to the incorporation of HPV DNA-based tests into routine ANC in Nigeria.

METHODS

We conducted nine focus group discussions with 82 pregnant women and 13 in-depth interviews with obstetricians and midwives at four health care facilities in Abuja, Nigeria. We used qualitative content analysis to analyze the data and the theory of planned behavior as a theoretical framework to examine the responses.

RESULTS

Pregnant women expressed a favorable attitude toward HPV DNA testing for cervical cancer screening as part of routine ANC. Acceptability of this approach was motivated by the expected benefits from early detection and treatment of cervical cancer. The factors most commonly cited as likely to influence acceptability and uptake of HPV DNA-based tests are recommendations by their care providers and mandating testing as part of ANC services. Discussants mentioned lack of awareness and affordability as factors that may inhibit uptake of HPV DNA-based cervical cancer screening. Midwives expressed concerns about the safety of sampling procedure in pregnancy, while obstetricians fully support the integration of HPV DNA-based testing into routine ANC.

CONCLUSION

Our results show that incorporating HPV DN-based cervical cancer screening into routine ANC is acceptable to pregnant women and health care providers. Making the test affordable and educating health care workers on its efficacy and safety if performed during ANC will enhance their willingness to recommend it and increase its uptake.

Commercially available molecular tests for human papillomaviruses (HPV): 2015 update

Commercial molecular tests for human papillomaviruses (HPV) are invaluable diagnostic tools in cervical carcinoma screening and management of women with cervical precancerous lesions as well as important research tools for epidemiological studies, vaccine development, and implementation and monitoring of vaccination programs. In this third inventory of commercial HPV tests, we identified 193 distinct commercial HPV tests and at least 127 test variants available on the market in 2015, which represents a 54% and 79% increase in the number of distinct HPV tests and variants, respectively, in comparison to our last inventory performed in 2012. Identified HPV tests were provisionally divided into eight main groups and several subgroups. Among the 193 commercial HPV tests, all but two target alpha-HPV types only. Although the number of commercial HPV tests with at least one published study in peer-reviewed literature has increased significantly in the last three years, several published performance evaluations are still not in line with agreed-upon standards in the HPV community. Manufacturers should invest greater effort into evaluating their products and publishing validation/evaluation results in peer-reviewed journals. To achieve this, more clinically oriented external quality-control panels and initiatives are required. For evaluating the analytical performance of the entire range of HPV tests currently on the market, more diverse and reliable external quality-control programs based on international standards for all important HPV types are indispensable. The performance of a wider range of HPV tests must be promptly evaluated on a variety of alternative clinical specimens. In addition, more complete HPV assays containing validated sample-extraction protocols and appropriate internal controls are urgently needed. Provision of a broader range of automated systems allowing large-scale HPV testing as well as the development of reliable, rapid, and affordable molecular point-of-care tests are priorities for the further improvement of HPV tests.

Knowledge, attitude, practice and barriers on vaccination against human papillomavirus infection: a cross-sectional study among primary care physicians in Hong Kong

This study explored the knowledge, attitude, practice and barriers to prescribe human papillomavirus (HPV) vaccines among private primary care physicians in Hong Kong. A self-administered questionnaire survey was conducted by sending letters to doctors who had joined a vaccination program for school girls. From 720 surveys sent, 444 (61.7%) completed questionnaires were returned and analyzed. For knowledge, few responded to questions accurately on the prevalence of cervical HPV (27.9%) and genital wart infection (13.1%) among sexually active young women in Hong Kong, and only 44.4% correctly answered the percentage of cervical cancers caused by HPV. For attitude, most agreed that HPV vaccination should be fully paid by the Government (68.3%) as an important public health strategy. Vaccination against HPV was perceived as more important than those for genital herpes (52.2%) and Chlamydia (50.1%) for adolescent health, and the majority selected adolescents aged 12–14 years as the ideal group for vaccination. Gardasil^® (30.9%) and Cervarix^® (28.0%) were almost equally preferred. For practice, the factors influencing the choice of vaccine included strength of vaccine protection (61.1%), long-lasting immunity (56.8%) and good antibody response (55.6%). The most significant barriers to prescribe HPV vaccines consisted of parental refusal due to safety concerns (48.2%), and their practice of advising vaccination was mostly affected by local Governmental recommendations (78.7%). A substantial proportion of physicians had recommended HPV vaccines for their female clients/patients aged 18–26 years for protection of cervical cancer (83.8%) or both cervical cancer and genital warts (85.5%). The knowledge on HPV infection was low among physicians in Hong Kong. Prescription of HPV vaccine was hindered by the perceived parental concerns and was mostly relied on Governmental recommendations. Educational initiatives should be targeted towards both physicians and parents, and the Government should consider full subsidy to enhance vaccine uptake rate.

Evidence that alpha-9 human papillomavirus infections are a major etiologic factor for oropharyngeal carcinoma in black South Africans

Human papillomavirus (HPV) infection, most commonly genotype 16 of the alpha-9 family, is implicated in the etiology of a subset of oropharyngeal squamous cell carcinomas (OPSC) worldwide. Data are scarce regarding OPSC in South Africans, and three prior studies suggest no significant etiologic role for HPV. We aimed to investigate for evidence of HPV etiology in OPSCs from black South Africans by polymerase chain reaction (PCR) methodologies with determination of HPV subtype by sequencing, in situ hybridization (ISH), and p16INK4a immunohistochemistry (IHC), as a surrogate marker for an HPV-driven tumor. It was hypothesized that HPV-driven tumors would be positive by PCR plus IHC and/or ISH whereas OPSCs with HPV background infections (HPV-passenger) would be positive by PCR alone. Formalin-fixed, paraffin embedded tissues from 51 OPSCs collected between 2005 and 2010 from 41 patients were analyzed for HPV by GP5?6? PCR (targeting the HPV L1 region), pU-1M/pU- 2R PCR (targeting the HPV E6/E7 region) and HPV-31 specific PCR (targeting the E5 region), chromogenic ISH, and p16INK4a IHC. All cases positive by PCR were subject to sequencing to determine HPV genotype. The patient mean age was 58.0 years and 88 % were male. Of the 51 evaluable tumors, 48 (94.1 %) were positive for HPV DNA by PCR: 25 (49.1 %) met criteria for an HPV-driven tumor, 23 (45.1 %) for HPV-passenger, and 3 (5.9 %) were HPV unrelated. Sequencing of the PCR-positive cases revealed the following genotypes: combined HPV-16 and 31 (41.7 %), HPV-31 (25.0 %), HPV-16 (22.9 %), combined HPV-16 and 18 (6.3 %), and a single case each of HPV 18 and HPV 33. Studies via ISH were negative in all cases. In accordance with worldwide trends but contrary to prior South African data, HPV likely plays an etiologic role in a significant subset (at least 49.1 %) of OPSC in black South Africans. We found that the alpha-9 HPV family, particularly HPV-16 and 31 either in combination or separately, to predominate in our sample tumors. The use of multiple PCR primers increased sensitivity of viral detection, and a HPV-31 specific primer confirmed the presence of this genotype in many samples. Further studies including HPV E6/E7 mRNA assays are needed to better elucidate the pathogenic role of HPV in black South African OPSCs.