Human papillomavirus DNA testing for cervical cancer screening in low-resource settings

High-risk human papillomavirus genotypes in previously unscreened reproductive-age women in Ethiopia: A community-based cohort study

High-risk human papillomavirus (hrHPV) genotype is needed for adequate cervical cancer screening and HPV vaccination program evaluation as recommended by different guidelines. We aimed to assess the rate of HPV infection and HPV genotype distribution using vaginal self-sampling in a cohort of unscreened reproductive-age women in Ethiopia. A community-based cohort study was conducted with women aged 23-46 living in Adama, Ethiopia. A total of 885 self-collected vaginal swabs were obtained and tested for hrHPV genotypes with the real-time polymerase chain reaction technique. The overall hrHPV prevalence was 21.1% (187/885, 95% confidence interval [CI]: 18.5-24.0). Among women living with human immunodeficiency virus, 46% (30/56) (95% CI: 33.7-59) were hrHPV positive compared with 19% (157/820) (95% CI: 16.2-22) of human immunodeficiency virus-negative women. The most frequent genotypes were HPV16 (3.1%), HPV51 (3.1%), HPV35 (2.6%), HPV56 (2.6%), HPV52 (2.4%), HPV31 (2.5%), and HPV39 (2.5%). Among the 187 HPV-positive women in self-samples, HPV 16/18 was found in 21% (39), HPV 16/18/45 was found in 24% (44), and HPV 16/18/31/33/45/52/58 was prevalent in 56% (104). Out of 116 biopsies, 7% (8) had cervical intraepithelial lesions and worse identified. Of these eight cervical intraepithelial lesions and worse patients, only 25% tested positive for HPV-16; none tested positive for HPV-18 or 45. One out of five women tested positive for hrHPV genotypes. Other HPV genotypes not covered by the quadrivalent HPV vaccine but associated with clinically significant cervical high-grade lesions or cancer were detected in 75%. It is more effective to prevent cervical cancer by switching to the nine-valent HPV vaccine.

Mapping the HPV Landscape in South African Women: A Systematic Review and Meta-Analysis of Viral Genotypes, Microbiota, and Immune Signals

This systematic review and meta-analysis evaluate human papillomavirus (HPV) prevalence, genotype distribution, and associations with cervicovaginal microbiota and cytokine profiles among South African women, where cervical cancer ranks as the second most common cancer. PubMed, SCOPUS, and Web of Science were searched for studies on HPV infection up to 21 September 2024. The pooled prevalence was estimated using a random-effects model, with subgroup analyses by province, sample type, and HIV status. Publication bias was evaluated using funnel plots and Egger's test. Of the 19,765 studies screened, 120 met the inclusion criteria, comprising 83,266 participants. Results indicate a high HPV burden, with a pooled prevalence of 58% (95% CI: 52-64%), varying regionally from 53% (95% CI: 41-65%) to 64% (95% CI: 55-73%), with some regions under-researched. Cervical samples had the highest HPV prevalence (60% (95% CI: 54-66%)), while non-genital samples were less studied. High-risk (HR) HPV types, notably HPV 16 (7.5%), HPV 35 (4.1%), and HPV 18 (3.9%), were prominent, with HPV 35 emphasizing the need for expanded vaccine coverage. HIV-positive women had a higher pooled HPV prevalence (63% (95% CI: 55-71%)). Funnel plot analysis and Egger's test suggested a potential publication bias (p = 0.047). HPV-positive women exhibited lower Lactobacillus levels and an increase in Bacterial Vaginosis (BV)-associated species like Gardnerella, potentially supporting HPV persistence. Cytokine analysis showed elevated MIP-1α and MIP-1β in HPV infections, though cytokine profiles may depend on HPV genotypes. These findings underscore the need for research on HPV-microbiome-immune interactions and call for comprehensive HPV-prevention strategies, including vaccines targeting regional HPV types and tailored interventions for HIV-positive populations.

High-risk human papillomavirus infection and cervical cytopathology: relationship with cervical nitric oxide levels

BACKGROUND

Nitric oxide (NO) may contribute to the persistence of high-risk human papillomavirus (hrHPV) infection, which has been linked to the development of premalignant lesions and cervical cancer. Our study aimed to examine the relationship between cervical NO metabolite (NOx) levels, hrHPV infection, and cytopathological findings. Additionally, we assessed cervical NOx levels as a biomarker for predicting hrHPV infection and epithelial atypia.

METHODS

The study involved 74 women who attended the Gynecology and Obstetrics outpatient clinics at Cairo University Hospitals between November 2021 and August 2022. Cervical samples were subjected to Pap testing, assessment of NOx levels by the Griess method, and detection of hrHPV DNA by real-time polymerase chain reaction.

RESULTS

High-risk HPV was detected in 37.8% of women. EA was found in 17.1% of cases, with a higher percentage among hrHPV-positive than negative cases (35.7% vs. 4.3%, p = 0.001). The most prevalent hrHPV genotype was HPV 16 (89.3%). The cervical NOx level in hrHPV-positive cases was significantly higher (37.4 µmol/mL, IQR: 34.5-45.8) compared to negative cases (2.3 µmol/mL, IQR: 1.2-9.8) (p = < 0.001). Patients with high-grade atypia showed significantly higher NOx levels (38.0 µmol/mL, IQR: 24.6-94.7) in comparison to NILM and low-grade atypia cases (5.0 µmol/mL, IQR: 1.6-33.3 and 34.5 µmol/mL, IQR: 11.7-61.7, respectively) (p = 0.006). Although the NOx levels among hrHPV-positive cases with low-grade atypia (40.4 µmol/mL, IQR: 33.3‒61.8) were higher than those with NILM (36.2 µmol/mL, IQR: 35.7‒44.0) and high-grade atypia (38.0 µmol/mL, IQR: 24.6‒94.7), the difference was not significant (p = 0.771). ROC curve analysis indicated that the cervical NOx cut-off values of > 23.61 µmol/mL and > 11.35 µmol/mL exhibited good diagnostic accuracy for the prediction of hrHPV infection and EA, respectively.

CONCLUSIONS

The high prevalence of hrHPV infection, particularly HPV 16, in our hospital warrants targeted treatment and comprehensive screening. Elevated cervical NOx levels are associated with hrHPV infection and high-grade atypia, suggesting their potential use as biomarkers for predicting the presence of hrHPV and abnormal cytological changes.

Cytology compared with Hybrid Capture 2 human papilloma virus cervical cancer screening in HIV positive and HIV negative South African women

OBJECTIVES

Cervical cancer is preventable and caused by persistent infection with oncogenic human papilloma virus (HPV) types. HPV screening is more sensitive and is the preferred screening test. HPV screening data are mainly from developed settings, and the purpose of this study was to investigate the performance of HPV screening in previously unscreened HIV positive and negative women.

METHODS

In this cross sectional multicenter study, liquid based cytology and HPV testing were performed on women attending different clinics. Patients with positive screening tests had colposcopy and biopsy or large loop excision of the transformation zone. Some women with normal screening had colposcopy and biopsy. Data of women with histology results, and data of HIV positive and negative women were analyzed for comparison. For women without histology results, data were imputed using a statistical model.

RESULTS

In 903 women with known HIV status, 683 (75.6%) had negative cytology, 202 women (22.4%) had abnormal cytology, and in 18 patients (2.0%) the results were uncertain. Mean age was 41.4 years (range 25-65). HPV tests were negative in 621 women (68.8%). In HIV positive women, 54.5% tested negative compared with 79.7% HIV negative women (p<0.0001). HPV screening had higher sensitivity (60.9%), but lower specificity (82.4%), compared with cytology (48.6% and 86.7%) for detection of cervical intraepithelial neoplasia (CIN) 2+ in all women. For detection of CIN 3+, HPV screening had higher sensitivity (70.4%) compared with cytology (62.9%), and specificity (75.5%) was lower compared with cytology at a threshold of atypical squamous cells of undetermined significance (ASCUS+) (82.4%).

CONCLUSION

HPV screening was more sensitive than cytology in HIV positive and HIV negative women, but specificity was lower. Although HPV screening should be the preferred screening test, cytology is a suitable screening test in HIV positive women in low resource settings.

TRIAL REGISTRATION NUMBER

NCT02956031.

Digital cervicography for cervical cancer screening in low-resource settings: A scoping review

Introduction

Digital cervicography (DC) is a method of capturing images for analysis during visual inspection with acetic acid (VIA) for cervical cancer screening. Cervical cancer is the 3rd leading cause of female cancer in the world with approximately 90 % of deaths due to cervical cancer occurring in low and middle income countries (LMICs). The need for cost-effective and sustainable methods for screening is vital in these settings. This scoping review systematically synthesizes published data illustrating the use of DC in screening programs. We aim to understand how digital cervicography is used, implemented, and impacted on programs.

Methods

Search of eight online databases identified 53 studies published between 1993 and 2021. Inclusion of articles were English language, cervical cancer screening program located in an LMIC, and DC as an intervention.

Results

All studies were cross-sectional studies (n = 53), with variation in terminology, uses, and device methods. Devices were grouped as either smartphones (n = 14), commercially available digital cameras (n = 17), or other (EVA®, n = 4; Cerviscope, n = 12; custom device, n = 4; or not specified, n = 2). Nineteen studies found acceptability and feasibility for DC in their screening programs. Various programs using DC found benefits such as task sharing, healthcare worker training, patient education and using images for review from a remote specialist or mentor.

Conclusion

The use of DC in LMICs is beneficial for support of healthcare workers, enhances quality improvement and demonstrates overall acceptability in screening programs. Advancing technologies for human papillomavirus (HPV) testing and cytology are common methods for cervical cancer screening, although are limited in LMICs. This scoping review demonstrates the different methods, uses, and benefit of digital cervicography in cervical cancer screening programs.

Prevalence and distribution of selected cervical human papillomavirus types in HIV infected and HIV uninfected women in South Africa, 1989-2021: A narrative review

Background

Human papillomavirus infection, a causative agent of cervical cancer, is of great concern, more so in populations with high HIV prevalence, such as South Africa.

Aim

This review aimed to examine the prevalence and distribution of selected cervical human papillomavirus (HPV) types in HIV infected and HIV uninfected women in South Africa.

Methods

PubMed and Web of Science databases were searched using key words. For data integrity, data was assessed by two authors independently. The study inclusion criteria comprised records on cervical HPV, HPV genotyping and HPV type distribution among South African women. Statistical analysis was performed using Social Science Statistics.

Results

Sixty-nine articles met the inclusion criteria for analysis. Data on cervical HPV prevalence and type distribution was available only for five of the nine provinces of South Africa. Only 4/69 studies used sequencing as an approach to identify HPV types. In a general population, HPV type 16 was the most frequent (8.80%), followed by types 35 (4.86%), 18 (4.14%), 58 and 52 with the frequency of 3.65% and 3.62%, respectively. Furthermore, the least frequent type was HPV 70 (0.74%). Both HIV infected and HIV uninfected populations had a higher prevalence of high-risk human papillomavirus (hrHPV) types 16, 18 and 35 than other HPV types; while HPV types 6, 11 and 70 were the least frequent types from these populations. Lastly, HPV 16 was the most predominant type among women with normal (2.03%) and abnormal cervical cytology (6.60%).

Conclusion

Expanding on HPV genotyping will improve the knowledge in patterns of HPV type distribution in South Africa that will further help in decision making to improve current diagnostics, and future vaccine development and assessment.

CIN extension at colposcopy: relation to treatment and blood parameters

OBJECTIVE

To determine the colposcopic lesion size that predicts the presence of residual lesion in patients with cervical intraepithelial neoplasia (CIN) 2/3, to aid gynaecologists in selecting conservative management.

METHODS

Data from 51 patients with low- and high-grade squamous intraepithelial lesions were evaluated. Colposcopic images were captured and lesion areas were calculated. Polymerase chain reaction (PCR) for human papillomavirus was performed. Laboratory parameters were evaluated. Receiver operating characteristic (ROC) curves were used to obtain cut-off values for lesion area. The performance of PCR in the detection of high-grade CIN was assessed. A flowchart was created to compare the costs of related procedures in the Brazilian health system.

RESULTS

For CIN 2/3 treated with excisional surgery, the best cut-off value for lesion area below which no residual lesion was present was 21 019 pixels² (58.87 mm²). The cut-off value that predicted compromised surgical margins was 155 577.65 pixels² (435.75 mm²). Among all patients with CIN, lesion area correlated inversely with neutrophil/lymphocyte ratio (NLR; r = -0.446, P = 0.001), platelet/lymphocyte ratio (PLR; r = -0.438, P = 0.001), and absolute number of leukocytes (r = -0.351, P = 0.011). Conservative clinical management with semi-annual clinical follow-up was found to reduce direct costs to the Brazilian Health System by R $909.82 (US $169.42).

CONCLUSION

CIN reflects systemic alteration, leading to altered NLRs, PLRs, and absolute numbers of leukocytes. Patients with high-grade CIN and colposcopic lesion areas <21 019 pixels² could benefit from conservative management, which would result in cost savings for the Brazilian health system.

Point-of-care cancer diagnostic devices: From academic research to clinical translation

Early and timely diagnosis of cancer plays a decisive role in appropriate treatment and improves clinical outcomes, improving public health. Significant advances in biosensor technologies are leading to the development of point-of-care (POC) diagnostics, making the testing process faster, easier, cost-effective, and suitable for on-site measurements. Moreover, the incorporation of various nanomaterials into the sensing platforms has yielded POC testing (POCT) platforms with enhanced sensitivity, cost-effectiveness and simplified detection schemes. POC cancer diagnostic devices provide promising platforms for cancer biomarker detection as compared to conventional in vitro diagnostics, which are time-consuming and require sophisticated instrumentation, centralized laboratories, and experienced operators. Current innovative approaches in POC technologies, including biosensors, smartphone interfaces, and lab-on-a-chip (LOC) devices are expected to quickly transform the healthcare landscape. However, only a few cancer POC devices (e.g. lateral flow platforms) have been translated from research laboratories to clinical care, likely due to challenges include sampling procedures, low levels of sensitivity and specificity in clinical samples, system integration and signal readout requirements. In this review, we emphasize recent advances in POC diagnostic devices for cancer biomarker detection and discuss the critical challenges which must be surmounted to facilitate their translation into clinical settings.

Cervical cancer: a meta-analysis, therapy and future of nanomedicine

Cervical cancer is one of the leading causes of female death, with an annual mortality rate exceeding 200,000 in developing communities. Despite the past decade bearing witness to a reduction in cervical cancer cases throughout developed countries, the prevalence in developing countries continues to rapidly rise. The increase in cervical cancer cases is attributed to the lack of financial resources and the unavoidable risk factors of the disease. Traditional means of anticancer therapy are compromised by reduced drug potency, non-specificity, negative side effects and the development of multiple drug resistance (MDR), which leads to a decrease in the long-term anticancer therapeutic efficacy. Recent advances in nanomedicine have elucidated the potential of nanoparticles to reduce the side effects and improve the survival rate of patients, by enhancing selective delivery and uptake of photosensitive, therapeutic and genetic material to cervical cancer cells, thereby enhancing antitumour efficiency. This review paper analyses the risk factors and epidemiology of cervical cancer globally, especially in developing communities, whilst demonstrating the enhanced anticancer treatment using selected nanoparticles.

National Policies to Prevent and Manage Cervical Cancer in East African Countries: A Policy Mapping Analysis

Policy mapping is used to provide evidence on effective interventions and highlight the necessary refinements of health policies. The goal of this work is to carry out legal mapping to identify and assess health policies for the prevention and management of cervical cancer in East African countries. Cervical cancer, as a largely preventable disease, is the cause of most cancer deaths among women in East African countries. Legal documents were searched uniformly from government websites, national cancer institute sites, and international and national legal databases, then the data were analyzed using the Nvivo12 software package. The sample of 24 documents includes policies, plans, guidelines, acts, and strategies from 12 East African countries. The emerging themes were screening, prevention, diagnosis, treatment, challenges, and mitigation efforts. A few binding policies, a significant discrepancy to international standards in at least four countries, patchy screening registries, and a lack of prophylactic vaccination against human papillomavirus incorporation into national immunization schedules are the main findings. This paper underlies the role of law in health and the need for transparent legal and regulatory tools to achieve a further reduction in cervical cancer mortality in East African countries.

Loop Electrosurgical Excision Procedure Treats Cervical Intraepithelial Neoplasia 2/3 Among HIV- and HIV+ Women in Kenya

OBJECTIVE

The aim of the study was to compare loop electrosurgical excision procedure (LEEP) as treatment for cervical intraepithelial neoplasia (CIN) 2/3 in HIV- versus HIV+ women.

MATERIALS AND METHODS

Seventy-five HIV- and 75 HIV+ women at 6 months or more after LEEP for CIN 2/3 were enrolled between September 2013 and November 2014 in this prospective cohort study at the cervical cancer screening clinic in Eldoret, Kenya. Visual inspection with acetic acid (VIA), followed by cervical cytology with conventional cytology, was performed on all women. Women with positive VIA or abnormal cervical cytology underwent colposcopy/biopsy. Lesion progression, persistence, and regression were assessed to quantify the efficacy of LEEP.

RESULTS

Post-loop electrosurgical excision procedure screening test showed both a negative VIA and normal cervical cytology in 64 (85%) of HIV- and 57 (77%) HIV+ women (risk difference = 8.3%, CI = -4.2% to 21%, p = .20). Eleven (15%) HIV- and 17 (23%) HIV+ (p = .20) women had positive VIA, abnormal cervical cytology, or both and were referred for colposcopy/biopsy. Twenty-one (8 HIV-, 13 HIV+) women were biopsied. Of the 8 HIV- women, 4 (50%) had CIN lesions that regressed, 3 (38.0%) persisted, and 1 (12%) progressed to invasive cancer after LEEP. Of the 13 HIV+ women, 6 (46%) had CIN lesions that regressed, 7 (54%) had CIN lesions that persisted, and no HIV+ women had CIN lesions that progressed after LEEP. There was no difference in estimated efficacies of LEEP for HIV- and HIV+ women (92.7% versus 89.4%, risk difference = 3.3%, CI = -4.8% to 15.3%, p = .85).

CONCLUSIONS

Loop electrosurgical excision procedure for CIN 2/3 is effective treatment for HIV- and HIV+ women in low-resource settings. Future efforts should improve follow-up after treatment.

Evaluating the implementation of cervical cancer screening programs in low-resource settings globally: a systematized review

PURPOSE

Cervical cancer disproportionately burdens low-resource populations where access to quality screening services is limited. A greater understanding of sustainable approaches to implement cervical cancer screening services is needed.

METHODS

We conducted a systematized literature review of evaluations from cervical cancer screening programs implemented in resource-limited settings globally that included a formal evaluation and intention of program sustainment over time. We categorized the included studies using the continuum of implementation research framework which categorizes studies progressively from "implementation light" to more implementation intensive.

RESULTS

Fifty-one of 13,330 initially identified papers were reviewed with most study sites in low-resource settings of middle-income countries (94.1%) ,while 9.8% were in low-income countries. Across all studies, visual inspection of the cervix with acetic acid (58.8%) was the most prevalent screening method followed by cytology testing (39.2%). Demand-side (client and community) considerations were reported in 86.3% of the articles, while 68.6% focused scientific inquiry on the supply side (health service). Eighteen articles (35.3%) were categorized as "Informing Scale-up" along the continuum of implementation research.

CONCLUSIONS

The number of cervical cancer screening implementation reports is limited globally, especially in low-income countries. The 18 papers we classified as Informing Scale-up provide critical insights for developing programs relevant to implementation outcomes. We recommend that program managers report lessons learnt to build collective implementation knowledge for cervical cancer screening services, globally.

Molecular characterisation of genital human papillomavirus among women in Southwestern, Nigeria

Background

Persistent infections with high-risk genital Human papillomavirus (HPV) especially types 16 and 18, are associated with cervical cancer. However, distribution of HPV types varies greatly across geographical regions and the available vaccines target only few types. This study was designed to determine the HPV types circulating in Southwestern Nigeria, thereby providing necessary information for effective control of the virus.

Methods

Endocervical swab samples were collected from a total of 295 consenting women attending routine cervical cancer screening, STI clinics and community-based outreach programme. Viral DNA was extracted from the samples and the consensus region of the HPV DNA was amplified by PCR using GP-E6/E7 primers. Type-specific nested multiplex PCR and Sanger sequencing were used to genotype the HPV isolates.

Results

In this study, 51 (17.3%) individuals were positive for HPV DNA using consensus primers that target the E6/E7 genes but only 48 (16.3%) were genotyped. A total of 15 HPV types (HPV-6, 16, 18, 31, 33, 35, 42, 43, 44, 52, 58, 66, 74, 81, 86) were detected, with HPV-31 being the most predominant (32.8%), followed by HPV-35 (17.2%) and HPV-16 (15.5%). Two rare HPV types; 74 and 86 were also detected. The HPV-74 isolate had three nucleotide (CCT) insertions at E7 gene that translated into amino acid proline. Highest nucleotide substitutions (n = 32) were found in HPV-44 genotype. Among positive individuals, 20.8% had dual infections and 86.2% had High-risk HPV types.

Conclusions

Multiple Human papillomavirus types co-circulated in the study. Most of the circulating Human papillomavirus are high-risk type with type 31 being the most predominant. Although the implication of HPV-74 with proline insertion detected for the first time is unknown, it may have effect on the transformation potential of the virus. Polyvalent HPV vaccine will be more effective for the infection control in Nigeria.

Prevalence of human papillomavirus infection and genotyping for population-based cervical screening in developed regions in China

We conducted a cross-sectional analysis to assess the distribution of human papillomavirus (HPV) types and explored an acceptable strategy for cervical screening in Shenzhen, China. A total of 2717 individuals ranging in age from 30–59 years were recruited. Clinical sensitivity and specificity as well as positive (PPV) and negative (NPV) predictive values were estimated. A triage strategy was regarded as acceptable when the NPV was at least 98.0%. 432 (15.9%) participants presented HPV positive. The five most prevalent HPV types were HPV52 (22.9%), HPV16 (12.7%), HPV53 (10.0%), HPV51 (8.6%), and HPV58 (8.1%). The CIN2+ risks for each HPV type were 40.0% for HPV33, 32.4% for HPV16, 18.2% for HPV58, 13.3% for HPV56, and 11.1% for HPV68 in descending order. Baseline cytology testing combined with HPV16/33/52/58 genotyping met the NPV thresholds at 98.6% with a PPV of 17.9%, demonstrating excellent clinical performance for detecting HPV types in CIN2+ patients. In conclusion, triaging HPV-positive women by baseline cytology combined with HPV16/58/33/52 genotyping is an acceptable strategy for cervical cancer screening in Shenzhen, China.

Evaluation of cytology versus human papillomavirus-based cervical cancer screening algorithms in Bhutan

To evaluate the performance of existing versus alternative cervical cancer screening protocols in Bhutan, cervical exfoliated cells were collected for cytology and high-risk human papillomavirus (HR-HPV) testing among 1,048 women aged 30-69 years. Conventional smears were prepared and read locally. HR-HPV was tested by GP5+/6+ polymerase chain reaction, followed by genotyping and human DNA methylation analysis among HR-HPV-positives, in Europe. Test positivity was 7.5% for ASCUS or worse (ASCUS+) cytology and 14.0% for HR-HPV. All women with ASCUS+ and/or HR-HPV positivity (n=192) were recalled for colposcopy, among whom a total of 29 cases of histologically confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+) were identified. An additional 7 CIN2+ cases were imputed among women without colposcopy. Corrected sensitivities for CIN2+ and CIN3+ were 61% and 74% for ASCUS+, 86% and 96% for HR-HPV, and 47% and 70% for ASCUS+ triage of HR-HPV. Specificity varied from 88% for HR-HPV up to 98% for ASCUS+ triage of HR-HPV, similarly for CIN2+ and CIN3+. Among HR-HPV-positive women with biopsies, methylation analysis offered similar discrimination of CIN2/3 and cervical cancer as ASCUS+, and better than HPV16/18 genotyping alone, but sample sizes were limited. In conclusion, the performance of cytology in Bhutan is in the mid-range of that reported in other screening settings. HR-HPV testing has the potential to improve detection of CIN2+, albeit with a higher referral rate for colposcopy. Cytological triage of HR-HPV-positives (performed in the absence of knowledge of HR-HPV status) reduced referral but missed more than one third of CIN2+.

Cytology versus HPV testing for cervical cancer screening in the general population

BACKGROUND

Cervical cancer screening has traditionally been based on cervical cytology. Given the aetiological relationship between human papillomavirus (HPV) infection and cervical carcinogenesis, HPV testing has been proposed as an alternative screening test.

OBJECTIVES

To determine the diagnostic accuracy of HPV testing for detecting histologically confirmed cervical intraepithelial neoplasias (CIN) of grade 2 or worse (CIN 2+), including adenocarcinoma in situ, in women participating in primary cervical cancer screening; and how it compares to the accuracy of cytological testing (liquid-based and conventional) at various thresholds.

SEARCH METHODS

We performed a systematic literature search of articles in MEDLINE and Embase (1992 to November 2015) containing quantitative data and handsearched the reference lists of retrieved articles.

SELECTION CRITERIA

We included comparative test accuracy studies if all women received both HPV testing and cervical cytology followed by verification of the disease status with the reference standard, if positive for at least one screening test. The studies had to include women participating in a cervical cancer screening programme who were not being followed up for previous cytological abnormalities.

DATA COLLECTION AND ANALYSIS

We completed a 2 x 2 table with the number of true positives (TP), false positives (FP), true negatives (TN), and false negatives for each screening test (HPV test and cytology) used in each study. We calculated the absolute and relative sensitivities and the specificities of the tests for the detection of CIN 2+ and CIN 3+ at various thresholds and computed sensitivity (TP/(TP + TN) and specificity (TN/ (TN + FP) for each test separately. Relative sensitivity and specificity of one test compared to another test were defined as sensitivity of test-1 over sensitivity of test-2 and specificity of test-1 over specificity of test-2, respectively. To assess bias in the studies, we used the Quality Assessment of Diagnostic test Accuracy Studies (QUADAS) tool. We used a bivariate random-effects model for computing pooled accuracy estimates. This model takes into account the within- and between-study variability and the intrinsic correlation between sensitivity and specificity.

MAIN RESULTS

We included a total of 40 studies in the review, with more than 140,000 women aged between 20 and 70 years old. Many studies were at low risk of bias. There were a sufficient number of included studies with adequate methodology to perform the following test comparisons: hybrid capture 2 (HC2) (1 pg/mL threshold) versus conventional cytology (CC) (atypical squamous cells of undetermined significance (ASCUS)+ and low-grade squamous intraepithelial lesions (LSIL)+ thresholds) or liquid-based cytology (LBC) (ASCUS+ and LSIL+ thresholds), other high-risk HPV tests versus conventional cytology (ASCUS+ and LSIL+ thresholds) or LBC (ASCUS+ and LSIL+ thresholds). For CIN 2+, pooled sensitivity estimates for HC2, CC and LBC (ASCUS+) were 89.9%, 62.5% and 72.9%, respectively, and pooled specificity estimates were 89.9%, 96.6%, and 90.3%, respectively. The results did not differ by age of women (less than or greater than 30 years old), or in studies with verification bias. Accuracy of HC2 was, however, greater in European countries compared to other countries. The results for the sensitivity of the tests were heterogeneous ranging from 52% to 94% for LBC, and 61% to 100% for HC2. Overall, the quality of the evidence for the sensitivity of the tests was moderate, and high for the specificity.The relative sensitivity of HC2 versus CC for CIN 2+ was 1.52 (95% CI: 1.24 to 1.86) and the relative specificity 0.94 (95% CI: 0.92 to 0.96), and versus LBC for CIN 2+ was 1.18 (95% CI: 1.10 to 1.26) and the relative specificity 0.96 (95% CI: 0.95 to 0.97). The relative sensitivity of HC2 versus CC for CIN 3+ was 1.46 (95% CI: 1.12 to 1.91) and the relative specificity 0.95 (95% CI: 0.93 to 0.97). The relative sensitivity of HC2 versus LBC for CIN 3+ was 1.17 (95% CI: 1.07 to 1.28) and the relative specificity 0.96 (95% CI: 0.95 to 0.97).

AUTHORS' CONCLUSIONS

Whilst HPV tests are less likely to miss cases of CIN 2+ and CIN 3+, these tests do lead to more unnecessary referrals. However, a negative HPV test is more reassuring than a negative cytological test, as the cytological test has a greater chance of being falsely negative, which could lead to delays in receiving the appropriate treatment. Evidence from prospective longitudinal studies is needed to establish the relative clinical implications of these tests.

CHAPTER 7 Methods for detection of HPV infection and its clinical utility

HPVs cannot be cultured and the detection of virus relies on a variety of techniques used in immunology, serology, and molecular biology. Currently the only FDA-approved commercially available method for the detection of HPV DNA is the Hybrid Capture assay, version hc2 (Digene, Gaithersburg, MD, USA) which is able to detect 13 high-risk types of HPV. The advantage of PCR-based methods of HPV DNA detection is that they allow for the identification of different types of HPV. This article discusses the advantages and disadvantages of the different methods of HPV DNA detection. HPV DNA testing can be used in a variety of clinical scenarios that include a primary screening test, particularly in women older than 30 years;as an adjunctive test to cytology;to triage women who have an equivocal cytologic finding, e.g., ASC-US, or for follow up post-treatment. In addition, HPV DNA testing can be performed on samples obtained by women themselves (so-called self-sampling), which may be useful in women who are resistant to undergoing gynecologic examinations.

Human papillomavirus infection in Rwanda at the moment of implementation of a national HPV vaccination programme

BACKGROUND

Cervical cancer is the most common female cancer in Rwanda that, in 2011, became the first African country to implement a national vaccination programme against human papillomavirus (HPV).

METHODS

To provide a robust baseline for future evaluations of vaccine effectiveness, cervical cell specimens were obtained from 2508 women aged 18-69 years from the general population in Kigali, Rwanda, during 2013/14. 20 % of women were HIV-positive. Samples were used for liquid-based cytology and HPV testing (44 types) with GP5+/6+ PCR.

RESULTS

HPV prevalence was 34 %, being highest (54 %) in women ≤19 years and decreasing to 20 % at age ≥50. Prevalence of high risk (HR) HPV and cytological abnormalities was 22 and 11 % respectively (including 2 % with high-grade squamous intraepithelial lesions, HSIL) decreasing with age. Age-standardised prevalence of HR HPV was 22 % (or 19 % among HIV-negative women), and HPV16 was the most common type. Prevalence of HPV and cytological abnormalities were significantly higher in HIV-positive than HIV-negative women, and the difference increased with age. Other significant risk factors for HPV positivity in multivariate analyses were high lifetime number of sexual partners, receiving cash for sex, and being a farmer. 40 % of women with HSIL were infected with HPV16/18 and there was no significant difference between HIV-positive and HIV-negative women.

CONCLUSIONS

This study confirms Rwanda to be a setting of high prevalence of HPV and cervical disease that is worsened by HIV. These data will serve as a robust baseline for future evaluations of HPV vaccine programme effectiveness.

A fully integrated paperfluidic molecular diagnostic chip for the extraction, amplification, and detection of nucleic acids from clinical samples

Paper diagnostics have successfully been employed to detect the presence of antigens or small molecules in clinical samples through immunoassays; however, the detection of many disease targets relies on the much higher sensitivity and specificity achieved via nucleic acid amplification tests (NAAT). The steps involved in NAAT have recently begun to be explored in paper matrices, and our group, among others, has reported on paper-based extraction, amplification, and detection of DNA and RNA targets. Here, we integrate these paper-based NAAT steps into a single paperfluidic chip in a modular, foldable system that allows for fully integrated fluidic handling from sample to result. We showcase the functionality of the chip by combining nucleic acid isolation, isothermal amplification, and lateral flow detection of human papillomavirus (HPV) 16 DNA directly from crude cervical specimens in less than 1 hour for rapid, early detection of cervical cancer. The chip is made entirely of paper and adhesive sheets, making it low-cost, portable, and disposable, and offering the potential for a point-of-care molecular diagnostic platform even in remote and resource-limited settings.

Prevalence of human papilloma virus (HPV) and its genotypes in cervical specimens of Egyptian women by linear array HPV genotyping test

BACKGROUND

The association of human papillomavirus (HPV) with cervical cancer is well established.

AIM

To investigate HPV genotype distribution and co-infection occurrence in cervical specimens from a group of Egyptian women.

METHODS

A group of 152 women with and without cervical lesions were studied. All women had cervical cytology and HPV testing. They were classified according to cytology into those with normal cytology, with squamous intraepithelial lesions (SIL) and invasive squamous cell carcinoma (SCC). Cervical samples were analyzed to identify the presence of HPV by PCR, and all positive HPV-DNA samples underwent viral genotype analysis by means of LINEAR ARRAY HPV Genotyping assay.

RESULTS

A total of 26 HPV types with a prevalence of 40.8 % were detected. This prevalence was distributed as follows: 17.7 % among cytologically normal females, 56.5, 3.2, and 22.6 % among those with LSIL, HSIL and invasive SCC respectively. Low-risk HPV types were detected in 81.8 % of the cytologically-normal women, in 5.7 % of those in LSIL women, and in 14.3 % of infections with invasive SCC, while no low-risk types were detected in HSIL. High-risk HPV types were detected in 18.2 % of infections in the cytologically normal women, 14.3 % of infections in LSIL, and in 21.4 % of invasive lesions. The probable and possible carcinogenic HPV were not detected as single infections. Mixed infection was present in 80 % of women with LSIL, in 100 % of those with HSIL, and in 64.3 % of those with invasive SCC. This difference was statistically significant. HPV 16, 18 and 31 were the most prevalent HR HPV types, constituting 41.9, 29.03 and 12.9 % respectively, and HPV 6, 62 and CP6108 were the most prevalent LR HPV types constituting 11.3, 9.7 and 9.7 % respectively.

CONCLUSION

These data expand the knowledge concerning HPV prevalence and type distribution in Egypt which may help to create a national HPV prevention program. HPV testing using the LINEAR ARRAY HPV Genotyping assay is a useful tool when combined with cytology in the diagnosis of mixed and non-conventional HPV viral types.

Performance of alternative strategies for primary cervical cancer screening in sub-Saharan Africa: systematic review and meta-analysis of diagnostic test accuracy studies

OBJECTIVE

To assess and compare the accuracy of visual inspection with acetic acid (VIA), visual inspection with Lugol's iodine (VILI), and human papillomavirus (HPV) testing as alternative standalone methods for primary cervical cancer screening in sub-Saharan Africa.

DESIGN

Systematic review and meta-analysis of diagnostic test accuracy studies.

DATA SOURCES

Systematic searches of multiple databases including Medline, Embase, and Scopus for studies published between January 1994 and June 2014.

REVIEW METHODS

Inclusion criteria for studies were: alternative methods to cytology used as a standalone test for primary screening; study population not at particular risk of cervical cancer (excluding studies focusing on HIV positive women or women with gynaecological symptoms); women screened by nurses; reference test (colposcopy and directed biopsies) performed at least in women with positive screening results. Two reviewers independently screened studies for eligibility and extracted data for inclusion, and evaluated study quality using the quality assessment of diagnostic accuracy studies 2 (QUADAS-2) checklist. Primary outcomes were absolute accuracy measures (sensitivity and specificity) of screening tests to detect cervical intraepithelial neoplasia grade 2 or worse (CIN2+).

RESULTS

15 studies of moderate quality were included (n=61,381 for VIA, n=46,435 for VILI, n=11,322 for HPV testing). Prevalence of CIN2+ did not vary by screening test and ranged from 2.3% (95% confidence interval 1.5% to 3.3%) in VILI studies to 4.9% (2.7% to 7.8%) in HPV testing studies. Positivity rates of VILI, VIA, and HPV testing were 16.5% (9.8% to 24.7%), 16.8% (11.0% to 23.6%), and 25.8% (17.4% to 35.3%), respectively. Pooled sensitivity was higher for VILI (95.1%; 90.1% to 97.7%) than VIA (82.4%; 76.3% to 87.3%) in studies where the reference test was performed in all women (P<0.001). Pooled specificity of VILI and VIA were similar (87.2% (78.1% to 92.8%) v 87.4% (77.1% to 93.4%); P=0.85). Pooled sensitivity and specificity were similar for HPV testing versus VIA (both P ≥ 0.23) and versus VILI (both P ≥ 0.16). Accuracy of VIA and VILI increased with sample size and time period.

CONCLUSIONS

For primary screening of cervical cancer in sub-Saharan Africa, VILI is a simple and affordable alternative to cytology that demonstrates higher sensitivity than VIA. Implementation studies are needed to assess the effect of these screening strategies on the incidence and outcomes of cervical cancer in the region.

Management of precancerous cervical lesions in iran: a cost minimizing study

BACKGROUND

Cervical cancer is a common, preventable and manageable disease in women worldwide.

OBJECTIVES

This study was conducted to determine the cost of follow-up for suspicious precancerous cervical lesions within a screening program using Pap smear or HPV DNA test through the decision tree.

MATERIALS AND METHODS

Patient follow-up processes were determined using standard guidelines and consultation with specialists to design a decision tree model. Costs of treatment in both public and private sectors were identified according to the national tariffs in 2010 and determined based on decision tree and provided services (visits to specialists, colposcopy, and conization) with two modalities: Pap smear and HPV DNA test. The number of patients and the mean cost of treatment in each sector were calculated. The prevalence of lesions and HPV were obtained from literature to estimate the cost of treatment for each woman in the population.

RESULTS

Follow-up costs were determined using seven processes for Pap smear and 11 processes for HPV DNA test. The total cost of using Pap smear and HPV DNA process for each woman in the population was 36.1$ and 174 $ respectively.

CONCLUSIONS

The follow-up process for patients with suspicious cervical lesions needs to be included in the existing screening program. HPV DNA test is currently more expensive than Pap smear, it is suggested that we manage precancerous cervical lesions with this latter test.

Cost-effectiveness analyses and their role in improving healthcare strategies

PURPOSE OF REVIEW

In this era of healthcare reform, attention is focused on increasing the quality of care and access to services, while simultaneously reducing the cost. Economic evaluations can play an important role in translating research to evidence-based practice and policy.

RECENT FINDINGS

Cost-effectiveness analysis (CEA) and its utility for clinical and policy decision making among U.S. obstetricians and gynecologists is reviewed. Three case examples demonstrating the value of this methodology in decision making are considered. A discussion of the methodologic principles of CEA, the advantages, and the limitations of the methodology are presented.

SUMMARY

CEA can play an important role in evidence-based decision making, with value for clinicians and policy makers alike. These studies are of particular interest in the field of obstetrics and gynecology, in which uncertainty from epidemiologic or clinical trials exists, or multiple perspectives need to be considered (maternal, neonatal, and societal). As with all research, it is essential that economic evaluations are conducted according to established methodologic standards. Interpretation and application of results should occur with a clear understanding of both the value and the limitations of economic evaluations.

Age-specific prevalence of human papilloma virus infection among Nigerian women

BACKGROUND

Inconsistent trends in HPV prevalence by age have been described in Africa. We examined the age prevalence pattern and distribution of 37 HPV-DNA types among urban Nigerian women.

METHODS

The study population was a sample of 278 women who presented to cervical cancer screening programs in Abuja, Nigeria, between April and August 2012. Using a nurse administered questionnaire, information on demographic characteristics and risk factors of cervical cancer was collected and samples of cervical exfoliated cells were obtained from all participants. Roche Linear Array HPV Genotyping Test® was used to characterize prevalent HPV and log-binomial regression models were used to examine the association between potential correlates and the prevalence of HPV infection.

RESULTS

The mean age (SD) of the women enrolled was 38 (8) years. The overall prevalence of HPV was 37%. HPV 35 was the most prevalent HPV type in the study population. Among women age ≤ 30 years, 52% had HPV infection compared to 23% of those women who were older than 45 years (p = 0.006). We observed a significant linear association between age and the prevalence of HPV infections. The prevalence ratio (PR) and 95% confidence interval (CI) was 2.26 (1.17, 4.34) for any HPV infection, 3.83 (1.23, 11.94) for Group 1 HPV (definite carcinogens), and 2.19 (0.99, 4.84) for Group 2a or 2b HPV (probable or possible carcinogens) types, among women aged 18-30 years, compared to women who were older than 45 years.

CONCLUSION

The prevalence of HPV infection was highest among younger women and decreased steadily with age among this population of urban Nigerian women.

Optimizing technology for cervical cancer screening in high-resource settings

Although historically successful in reducing the burden of cervical cancer, Papanicolaou (Pap) testing faces numerous limitations. A growing body of evidence suggests that modern screening practice will benefit from primary screening for high-risk human papillomavirus (HPV) infection, the causative agent of cervical cancer. Molecular tests detecting the presence of HPV nucleic acids consistently demonstrate high sensitivity relative to Pap testing, and provide reliable, dichotomous results. Pap cytology is ideally suited to triage HPV-positive cases owing to its high test specificity, and the accuracy of cytological readings will be maximized in high-prevalence conditions. This algorithm of primary HPV testing with Pap triage has been shown to maintain the high sensitivity of HPV testing without compromising Pap cytology's strong ability to rule out falsely positive diagnoses. Given the anticipated decline of high-risk HPV-16 and -18 infections in the emergent post-HPV vaccination era, highly sensitive primary HPV testing is especially warranted. Novel screening technologies that identify HPV viral gene expression continue to emerge and seek to complement current HPV testing by identifying those women who may be at risk of progressive disease. How to best incorporate these new technologies into clinical practice presents our next great challenge. Implementation of novel algorithms for cervical screening is not a trivial task. Avoidance of exceedingly complex screening algorithms is an important priority.

American cancer society guideline for the early detection of cervical neoplasia and cancer

An update to the American Cancer Society (ACS) guideline regarding screening for the early detection of cervical neoplasia and cancer, based on recommendations from a formal review and recent workshop, is presented. The new screening recommendations address when to begin screening, when screening may be discontinued, whether to screen women who have had a hysterectomy, appropriate screening intervals, and new screening technologies, including liquid-based cytology and HPV DNA testing.

Human papillomavirus types 16 and 18 and the prognosis of patients with stage I cervical cancer

OBJECTIVE

This study sought to evaluate the prevalence of human papillomavirus (HPV) types 16 and 18 in women with clinical stage IB cervical cancer treated by radical hysterectomy with pelvic lymphadenectomy as well as to establish a correlation between HPV type and cancer prognosis.

METHODS

A single-center cohort study was conducted with 86 patients who had undergone radical hysterectomy for stage I cervical cancer. Prognostic factors and the presence of HPV 16 and 18 were analyzed using a polymerase chain reaction assay. A univariate analysis using Kaplan-Meier curves was conducted to estimate survival.

RESULTS

The prevalence of HPV 16 in the study group was 65.3%, and the prevalence of HPV 18 was 33.3%. The prevalence of infection with both viruses was 26.9%. Overall survival at 5 years was 91% among women with HPV 18 and 96% among those without this virus type (p=0.133). Among the women with HPV 16, the overall survival was 94%, whereas this rate was 96% among those without this virus type (p=0.663). Disease-free survival was unaffected by the presence of HPV type 16 or 18.

CONCLUSION

In the present study, despite the high prevalence of HPV types 16 and 18, the presence of these virus types did not affect the prognosis of patients with stage I cervical cancer who underwent radical hysterectomy.

Ultrabright fluorescent mesoporous silica nanoparticles for prescreening of cervical cancer

We report on the first functional use of recently introduced ultrabright fluorescent mesoporous silica nanoparticles, which are functionalized with folic acid, to distinguish cancerous and precancerous cervical epithelial cells from normal cells. The high brightness of the particles is advantageous for fast and reliable identification of both precancerous and cancerous cells. Normal and cancer cells were isolated from three healthy women and three cancer patients. Three precancerous cell lines were derived by immortalization of primary cultures of normal cells with human papillomavirus type-16 (HPV-16) DNA. We observed substantially different particle internalization by normal and cancerous/precancerous cells after a short incubation time of 15 minutes. Compared to HPV-DNA and cell pathology tests, which are currently used for prescreening of cervical cancer, we demonstrated that the specificity of our method was similar (94-95%), whereas its sensitivity was significantly better (95-97%) than the sensitivity of those currently used tests (30-80%).

FROM THE CLINICAL EDITOR

This team of investigators reports on the development of a new screening test for cervical cancer using ultrabright fluorescent mesoporous silica nanoparticles functionalized with folic acid, enabling significantly better sensitivity (95-97% vs. 30-80%) and maintained specificity (94-95%) compared with current clinical tests. This test should find a way to clinical use in the near future.

Trends in cervical cancer screening in developing countries

Developing countries suffer the highest burden of cervical cancers but have the lowest resources. Effective cervical cytology screening programme, along with a network of diagnostic and therapeutic colposcopy centres, like developed countries, is almost impossible to be reproduced in developing countries. Visual inspection methods [e.g., Visual inspection with Lugol’s iodine (VILI) and Visual Inspection with Acetic Acid (VIA)] which are cheaper, require less expertise and have the advantage of possible treatment in one setting have been shown to be effective alternatives. The sensitivity to detect CIN2+, by VIA and VILI, have been shown to be 80% and 91% respectively, with a specificity rate of 92% and 85% respectively. Screening by human papillomavirus (HPV) testing has high sensitivity (96.4%) but low specificity (94.1%) to detect CIN2+, when compared to Pap Smear (sensitivity, 55.4% and specificity, 96.8%). A single lifetime HPV testing in a large unscreened population has been shown to significantly reduce cervical cancer incidence and mortality when compared to cervical cytology, VIA or no screening. HPV testing of self-collected vaginal specimens also helps to overcome religious and socio-cultural barriers towards pelvic examination amongst women in developing countries. Current HPV testing methods are expensive, skill/infrastructure demanding and takes time to produce results. A cheaper HPV test, called careHPV™, which is able to provide results within 2.5 h and requires minimal skill/infrastructure to operate, was designed for use in developing countries. One stop screen and treat facilities using VIA or rapid HPV testing, and cryotherapy, can overcome non-compliance to follow-up which is a major issue in developing countries. Cure rates of 81.4% for CIN1, 71.4% for CIN2 and 68.0% for CIN3 at 6 mo after treatment have been reported. Incorporating telemedicine with cervicography of VIA or VILI or even telecolposcopy, has great potential in cervical cancer screening, especially in countries with vast geographical areas.

Prevention of cervical cancer in women with ASCUS in the Brazilian Unified National Health System: cost-effectiveness of the molecular biology method for HPV detection

This study aimed to assess the performance of PCR as a means of detecting HPV 16/18 compared to the single probe-based PCR for detecting high-risk HPV, and evaluate these methods for detecting cervical intraepithelial neoplasia (CIN) in follow-ups for ASCUS testing. It also compares the costs of cytology, PCR methods, colposcopy and biopsy in the Brazilian Unified National Health System. Of the 81 patients with ASCUS, 41 (50.6%) tested positive for HPV 16/18 in PCR testing and 47 (58.02%) tested positive for high-risk HPV with single probe-based PCR testing. The negative predictive value was 93.75% for HPV 16/18 PCR and 100% for single probe-based PCR in cases that progressed to high-grade CIN. The annual costs of patient referral were the following: R$2,144.52 for referral of patients with ASCUS cytology for colposcopy; R$6,307.44 for referral of patients with ASCUS cytology and PCR positive for HPV 16/18 or colposcopy; R$3,691.80 for referral of patients with ASCUS cytology with single probe-based PCR positive for high-risk HPV. Therefore, cost per user can be reduced by performing single probe-based PCR for high-risk HPV on patients with ASCUS.

Application of TruScreen in detecting ASCUS patients

OBJECTIVE

To explore the application of cervical cancer screening system, TruScreen in detecting atypical squamous cell of undetermined significance (ASCUS) patients.

METHODS

A total of 42 cases were selected, who were diagnosed as ASCUS by thinprep cytologic test (TCT). Area from site 15 to 20, site 21 to 32 were detected by TruScreen. And the result was compared with those of cases which had positive pathological result of cervical biopsy.

RESULTS

There were 16 cases with abnormal pathological result in ASCUS cases, including 6 cases with cervical intraepithelial neoplasia (CIN) I, 6 cases with CIN II, 3 cases with CIN III and 1 case with infiltrating carcinoma. The consistency between TCT and pathological test was 38.10% (16/42). The positive rate of TruScreen at site 15-20 was 61.91% (26/42). There was significant difference in consistency with pathological test between TCT and TruScreen (x(2)=4.762, P=0.029). The positive rate of TruScreen at site 21-32 was 66.67% (28/42)(Kappa=0.181, P=0.016). There was significant difference in consistency with pathological test between TCT and TruScreen (x(2)=9.4919, P=0.002). And no case was missed when site 21-32 of patients with CINII and above were detected by TruScreen.

CONCLUSIONS

TruScreen is effective in detecting ASCUS patients.

Human papillomavirus deoxyribonucleic acid testing in developed countries

Cervical cancer has been largely eliminated in developed countries with the implementation of cytology-based screening programmes that depend on a call-recall system, followed by colposcopy and biopsy, treatment of precancerous lesions and follow up. With the discovery that persistent infection with high-risk human papillomavirus types is necessary for the development of cervical cancer, several tests for human papillomavirus deoxyribonucleic acid have been developed that can identify women at risk. Human papillomavirus deoxyribonucleic acid testing is more sensitive and only slightly less specific than cytology for detecting cervical intraepithelial neoplasia. It is also more reproducible, with the potential for self-sampling. Human papillomavirus genotyping, messenger RNA analysis and other biomarkers can help to further stratify this group and diminish referrals to colposcopy. Initially, human papillomavirus testing was used as an adjunct to cytology for triage of borderline cases, but evidence has shown its superiority as a screening method and in the follow up of women treated for cervical intraepithelial neoplasia.

Oncogenic HPV Types Infection in Adolescents and University Women from North Portugal: From Self-Sampling to Cancer Prevention

This study aimed to characterize the HPV infection status in adolescents and young university women in Portugal. The distribution of HPV genotypes was evaluated by PCR DNA genotyping after self-sampling collection from 435 women of exfoliated cervical cells using a commercial kit. We observed an overall frequency of HPV infection of 11.5%. Furthermore, HPV DNA prevalence was 16.6% in those young women that self-declared as sexually active. The more frequently detected HPV types were 31, 16, 53, and 61. Statistical analysis identified median age (OR = 3.56; P = 0.001), the number of lifetime sexual partners (OR = 4.50; P < 0.001), and years of sexual activity (OR = 2.36; P = 0.008) as risk factors for HPV acquisition. Hence, our study revealed that oncogenic HPV infection is common in young asymptomatic women Portuguese women, with a history of 2-5 sexual partners and over 2 year of sexual activity. Moreover, these results demonstrate that HPV detection performed in self-collected samples may be important to appraise better preventive strategies and to monitorize the influence of vaccination programmes within different populations.

Canadian oncogenic human papillomavirus cervical infection prevalence: systematic review and meta-analysis

BACKGROUND

Oncogenic human papillomavirus (HPV) infection prevalence is required to determine optimal vaccination strategies. We systematically reviewed the prevalence of oncogenic cervical HPV infection among Canadian females prior to immunization.

METHODS

We included studies reporting DNA-confirmed oncogenic HPV prevalence estimates among Canadian females identified through searching electronic databases (e.g., MEDLINE) and public health websites. Two independent reviewers screened literature results, abstracted data and appraised study quality. Prevalence estimates were meta-analyzed among routine screening populations, HPV-positive, and by cytology/histology results.

RESULTS

Thirty studies plus 21 companion reports were included after screening 837 citations and 120 full-text articles. Many of the studies did not address non-response bias (74%) or use a representative sampling strategy (53%). Age-specific prevalence was highest among females aged < 20 years and slowly declined with increasing age. Across all populations, the highest prevalence estimates from the meta-analyses were observed for HPV types 16 (routine screening populations, 8 studies: 8.6% [95% confidence interval 6.5-10.7%]; HPV-infected, 9 studies: 43.5% [28.7-58.2%]; confirmed cervical cancer, 3 studies: 48.8% [34.0-63.6%]) and 18 (routine screening populations, 8 studies: 3.3% [1.5-5.1%]; HPV-infected, 9 studies: 13.6% [6.1-21.1%], confirmed cervical cancer, 4 studies: 17.1% [6.4-27.9%].

CONCLUSION

Our results support vaccinating females < 20 years of age, along with targeted vaccination of some groups (e.g., under-screened populations). The highest prevalence occurred among HPV types 16 and 18, contributing a combined cervical cancer prevalence of 65.9%. Further cancer protection is expected from cross-protection of non-vaccine HPV types. Poor study quality and heterogeneity suggests that high-quality studies are needed.

SOGC–GOC–SCC Joint Policy Statement. No. 255, March 2011. Cervical cancer prevention in low-resource settings

OBJECTIVE

To help care providers understand the current status of cervical cancer in low-resource countries.

OPTIONS

The most effective and practical options for cervical screening and treatment in low-resource countries are evaluated.

OUTCOMES

Improvement in rates of prevention and early detection of cervical cancer in low-resource countries.

EVIDENCE

PubMed or Medline, CINAHL, and The Cochrane Library were searched for studies published in English between January 2006 and December 2009. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table). RECOMMENDATIONS 1. All girls 9 years old or over should have access to the cervical cancer vaccine before they become sexually active. (I-A) 2. Cervical cancer screening by visual inspection with acetic acid is suggested for low-resource settings acceptable. Cervical cytology or human papillomavirus testing may also be used when practical. (II-2B) 3. Cryotherapy is a safe, effective, and low-cost therapy that should be included in pre-invasive cervical cancer treatment. (III-B) 4. All countries should have a documented cervical cancer prevention strategy that includes public education built on existing outreach programs. (III-C) 5. Countries should define a centre or centres of excellence for the management of cervical cancer. (III-C) Because these units would serve a larger population, they would be able to identify leaders and develop their skills, and would be able to invest in costly radiation equipment. 6. All women with cervical cancer should have access to pain management. (III-C).

HPV prevalence and accuracy of HPV testing to detect high-grade cervical intraepithelial neoplasia

Concern was raised on using testing for high-risk (HR) human papillomavirus (HPV) in cervical cancer screening in populations where HPV prevalence is high. The impact of HR HPV prevalence on the efficiency of HPV test-based screening has never been directly evaluated. A meta-regression of the relationship between HR HPV prevalence and the specificity and positive predictive value (PPV) of HPV DNA testing for the presence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was performed. Only studies that used Hybrid Capture 2 (HC2) were included. Country income (low-medium vs. high) was used as a proxy of previous screening. Twenty-six populations from 20 studies were included. For a 10% increase in HR HPV prevalence, HC2 specificity decreased by 8.41% [95% confidence interval (CI): 8.02-8.81], whereas PPV increased by 4.74% (95% CI: 2.45-7.03). HR HPV prevalence explained 98% of the variability in HC2 specificity and 38% of the variability in PPV. Country income did not affect specificity, but low-medium income was associated with higher PPV (3.81%; 95% CI: 1.53-6.10) after adjustment for HR HPV prevalence. When HR HPV prevalence is high, the specificity of HPV testing for CIN2+ decreases, but PPV does not decrease and it is high in inadequately screened populations. The number of HPV-positive women needing further assessment or treatment per CIN2+ case detected will therefore decrease and screening efficiency will improve. This is explained by the fact that HR HPV causes CIN2+: an increase in HR HPV prevalence is inevitably accompanied by an increase in CIN2+.

The presence of Y chromosomal deoxyribonucleic acid in the female vaginal swab: possible implications for human papillomavirus testing

BACKGROUND

Vaginal self-sampling for human papillomavirus (HPV) detection is the focus of recent research. However, it has been shown previously that male DNA can be detected in vaginal swabs. The aim of this study was to investigate whether a female vaginal swab may reflect a male active HPV infection.

METHODS

Eleven women volunteered to take vaginal samples. The first sample was taken within hours after unprotected intercourse, the others each following morning for five consecutive days. On these samples, a Y-chromosomal locus, as a surrogate marker for HPV, was amplified by PCR. To investigate the prevalence of male DNA in self-obtained vaginal swabs, 282 swabs from 16 women enrolled in an ongoing HPV follow-up study were tested.

RESULTS

All baseline samples from the 11 women were positive for male DNA. In the follow-up samples, positivity ranged from day 1 till day 5, with a sharp drop from day 2 (91%) to day 3 (36%). Of 282 swabs, 23 (8.2%) were positive for male DNA. However, 10 of these 23 swabs were provided by one single woman.

DISCUSSION

Since HPV can be deposited by the male in the vagina, either through semen, or through exfoliated epithelial cells, our results are of some importance when testing for HPV in vaginal swabs. It is conceivable that women with acquired immunity to HPV, but with an HPV positive partner, are found to be HPV positive in the swab. However, larger studies on more diverse populations are warranted.

The prevalence of human papillomavirus infection in Mombasa, Kenya

OBJECTIVES

A human papillomavirus (HPV) prevalence survey was done in Mombasa, Kenya, to improve the knowledge of HPV prevalence and genotype distribution in sub-Saharan African countries overall, and in women of different ages.

METHODS

HPV prevalence was assessed using PCR in women older than 15 years attending family planning and mother-child care services.

RESULTS

Among 496 women, HPV prevalence was high (42.3%; 95% CI: 37.9-46.8; world age-standardized). Moreover, 46% of HPV-positive women harbored multiple-type infections. The most common types were HPV58 (10.5% of women), HPV16 (7.7%), HPV53 (6.7%), HPV18 (4.6%), and HPV6 (4.4%), and the prevalence of any high-risk HPV type was 28.8%. HPV prevalence was elevated among all age-groups (range 36.4-45.7%). Independent associations with HPV positivity were found for being in a polygamous marriage (OR = 1.7) and lifetime number of sexual partners (OR for ≥ 3 vs. 1 = 1.5), although they were of only borderline statistical significance.

CONCLUSIONS

These findings differ from other world regions, showing a high HPV burden in all age-groups with a high proportion of multiple-type infections. Our data strengthen the urgency of HPV vaccination in Kenya but also highlight the elevated number of women who would have positive results in an HPV-based screening program in the country.

Comparison of Hybrid capture 2 testing at different thresholds with cytology as primary cervical screening test

Background:

We evaluated the performance of primary high-risk human papillomavirus (hrHPV) testing by hybrid capture 2 (HC2) with different thresholds for positivity, in comparison with conventional cytology.

Methods:

We used data of 25 871 women (aged 30–60 years) from the intervention group of the VUSA-Screen study (VU University Medical Center and Saltro laboratory population-based cervical screening study), who were screened by cytology and hrHPV. Primary outcome measure was the number of cervical intraepithelial neoplasia grade 3 or higher (CIN3+), detected within 3 years. We compared baseline cytology testing with three possible hrHPV screening strategies at different relative light unit/cutoff (RLU/CO) thresholds.

Results:

Compared with baseline cytology testing, hrHPV DNA testing as a sole primary screening instrument did not yield a superior sensitivity, as well as lower colposcopy referral rate and lower false positivity rate at any RLU/CO threshold. The hrHPV screening at 1 RLU/CO threshold with cytology triage at baseline and at 12 months revealed the highest sensitivity for CIN3+ (relative sensitivity of 1.32), although still displaying a lower colposcopy referral rate than cytology testing (relative colposcopy rate of 0.94). Higher thresholds (>1RLU/CO) yielded lower colposcopy rates, but resulted in substantial loss in sensitivity.

Conclusions:

The hrHPV testing at the commonly used threshold of 1 RLU/CO with cytology triage at baseline and at 12 months showed a much higher sensitivity with a lower colposcopy referral rate compared with cytology testing.

Screening for Cervical Cancer with the Human Papillomavirus Test in an Area of Central Italy with No Previous Active Cytological Screening Programme

Objective

We report performance indicators and costs of the first round of a cervical cancer screening programme based on the human papillomavirus (HPV)-DNA test.

Methods

We implemented a demonstration study using HPV as the primary test in Guidonia, Italy (90,000 inhabitants). All women aged 25-64 were invited to undergo a Hybrid Capture II high-risk HPV test. Two cervical samplings, smear and liquid, were taken. The smear was dyed and interpreted only for HPV-positive (HPV+) women. Women with a non-negative Pap smear were referred for colposcopy, women HPV+/cytology negative were referred to one-year follow-up with HPV. A cost-analysis indicated the price at which the HPV-based and cytological screening would cost the same per screened woman and per lesion found.

Results

Of 24,000 women invited, 7639 accepted and 427 (5.6%) were HPV+; 141 (34%) of these had a non-negative Pap test, and 20 cervical intraepithelial neoplasia (CIN) 2 or higher were found (positive predictive value 15%). Compliance to one-year follow-up was 58% (166/286); 90 (54%) were HPV-positive and five additional lesions were found (positive predictive value 9%; overall detection rate 3.4/1000). The cost analysis showed that at a price of 8.3 euros per HPV DNA test, the strategy using HPV as primary test followed by cytological triage would cost the same per screened woman, while at a price of 12.7 euros it would have the same cost per CIN2+ found.

Conclusion

The workload for management of positive women was similar to cytological screening. Low compliance to one-year follow-up was the main barrier to effectiveness. The price of HPV test should be about 9 euros to maintain the same screening budget, and can go as high as 13 euros per lesion found.