Human papillomavirus testing in primary cervical screening

Impact of human papillomavirus age-related prevalence and vaccination levels on interpretation of cervical screening modalities: a modelling study

OBJECTIVE

Cervical screening is a life-saving intervention, which reduces the incidence of and mortality from cervical cancer in the population. Human papillomavirus (HPV) based screening modalities hold unique promise in improving screening accuracy. HPV prevalence varies markedly by age, as does resultant cervical intraepithelial neoplasia (CIN), with higher rates recorded in younger women. With the advent of effective vaccination for HPV drastically reducing prevalence of both HPV and CIN, it is critical to model how the accuracy of different screening approaches varies with age cohort and vaccination status. This work establishes a model for the age-specific prevalence of HPV factoring in vaccine coverage and predicts how the accuracy of common screening modalities is affected by age profile and vaccine uptake.

DESIGN

Modelling study of HPV infection rates by age, ascertained from European cohorts prior to the introduction of vaccination. Reductions in HPV due to vaccination were estimated from the bounds predicted from multiple modelling studies, yielding a model for age-varying HPV and CIN grades 2 and above (CIN2+) prevalence.

SETTING

Performance of both conventional liquid-based cytology (LBC) screening and HPV screening with LBC reflex (HPV reflex) was estimated under different simulated age cohorts and vaccination levels.

PARTICIPANTS

Simulated populations of varying age and vaccination status.

RESULTS

HPV-reflex modalities consistently result in much lower incidence of false positives than LBC testing, with an accuracy that improves even as HPV and CIN2+ rates decline.

CONCLUSIONS

HPV-reflex tests outperform LBC tests across all age profiles, resulting in greater test accuracy. This improvement is especially pronounced as HPV infection rates fall and suggests HPV-reflex modalities are robust to future changes in the epidemiology of HPV.

Impact of HPV testing in opportunistic cervical screening: Support for primary HPV screening in the United States

Human papillomavirus (HPV) testing for cervical screening increases diagnosis of precancer and reduces the incidence of cervical cancer more than cytology alone. However, real-world evidence from diverse practice settings is lacking for the United States (U.S.) to support clinician adoption of primary HPV screening. Using a population-based registry, which captures all cervical cytology (with or without HPV testing) and all cervical biopsies, we conducted a real-world evidence study of screening in women aged 30 to 64 years across the entire state of New Mexico. Negative cytology was used to distinguish cotests from reflex HPV tests. A total of 264 198 cervical screening tests (with exclusions based on clinical history) were recorded as the first screening test between 2014 and 2017. Diagnoses of cervical intraepithelial neoplasia grades 2 or 3 or greater (CIN2+, CIN3+) from 2014 to 2019 were the main outcomes. Of cytology-negative screens, 165 595 (67.1%) were cotests and 4.8% of these led to biopsy within 2 years vs 3.2% in the cytology-only group. Among cytology-negative, HPV tested women, 347 of 398 (87.2%) CIN2+ cases were diagnosed in HPV-positive women, as were 147 of 164 (89.6%) CIN3+ cases. Only 29/921 (3.2%) CIN3+ and 67/1964 (3.4%) CIN2+ cases were diagnosed in HPV-negative, cytology-positive women with biopsies. Under U.S. opportunistic screening, across a diversity of health care delivery practices, and in a population suffering multiple disparities, we show adding HPV testing to cytology substantially increased the yield of CIN2+ and CIN3+. CIN3+ was rarely diagnosed in HPV-negative women with abnormal cytology, supporting U.S. primary HPV-only screening.

A systematic review and meta-analysis of the diagnostic effectiveness of human papillomavirus methylation biomarkers for detection of cervical cancer

Background: The aim of this systematic review and meta-analysis was to assess the evidence for the diagnostic effectiveness of human papillomavirus (HPV) methylation biomarkers for detection of cervical cancer. Methods: PubMed, Embase and Web of Science were searched. Nine articles focusing on HPV methylation for detection of precancerous and cancerous cervical lesions were included. The QUADAS-2 tool was used for quality assessment. The receiver operating characteristic (ROC) was the main diagnostic performance parameter extracted. Results: Of the nine articles included in this study, seven were of moderate quality and two were of high quality. A meta-analysis of the ROC for 27 HPV methylation biomarkers revealed an overall pooled ROC of 0.770 (95% CI: 0.720-0.819; I²: 98.4%; Q: 1537.4; p < 0.01). Four methylation biomarkers had strong diagnostic ability (ROC > 0.900), 17 were moderate (ROC: 0.7000-0.8999) and six were poor (ROC < 0.700). Conclusion: HPV methylation biomarkers hold significant promise as independent screening tests for the detection of cervical precancerous and cancerous lesions.

Acceptability and Feasibility of HPV Self-Sampling as an Alternative Primary Cervical Cancer Screening in Under-Screened Population Groups: A Cross-Sectional Study

Background: Cervical cancer is one of the most common cancers in women and about 90% of cervical cancer can be reduced by regular screening. The Pap smear has been well in place as a primary cervical screening method since 1950s; however, coverage is still not optimal. This study explored the feasibility of HPV self-sampling in two under-screened population groups in Hong Kong (HK): never screened and not regularly screened females, to estimate the uptake rate and preference rate in the future. Materials and Methods: This was a cross-sectional study to explore the acceptability and feasibility of HPV self-sampling in two age groups: aged 25–35 and aged ≥45, which were reported as the highest proportion of the under-screened population in HK between 2017 and 2018. The study invited eligible women from an HPV study cohort to perform HPV self-sampling at home by themselves. The number of specimens returned from participants was recorded and used to determine the feasibility of HPV self-sampling in the community. The participants were asked to fill in the questionnaires before and after HPV self-sampling to indicate their attitudes, acceptability, and future preference for HPV self-sampling as an acceptable alternative primary cervical cancer screening method. Results: A total of 177 subjects participated in the present study and have achieved a good overall uptake rate of 73% (129/177) who returned the self-collected cervicovaginal sample for HPV testing. Among the under-screened population, there was a higher response rate in aged ≥45 than those aged 25–35. The findings also revealed that women who were under-screened, including those who have never been screened, were more likely to prefer HPV self-sampling than those who had regular screening. This study found that the acceptability of HPV self-sampling was fairly positive among the respondents. The findings also indicated that HPV self-sampling was not only beneficial to enhance their health awareness but also to promote the cervical cancer screening uptake rate, especially among the under-screened or never screened populations. Conclusions: HPV self-sampling would be a solution to overcome the perceived barriers in clinician-based screening. The findings also indicated that it could be feasible to use as an alternative primary cervical cancer screening.

Improved Rates of Cervical Cancer Screening Among Transmasculine Patients Through Self-Collected Swabs for High-Risk Human Papillomavirus DNA Testing

Introduction: Nearly all cervical cancer cases are caused by one of several high-risk strains of the human papillomavirus (hr-HPV). Transmasculine (TM) individuals (persons who have a masculine spectrum gender identity, but were recorded female at birth) have low adherence to standard cervical cancer screening modalities. Introduction of self-collected vaginal swabs for hr-HPV DNA testing may promote initiation and adherence to cervical cancer screening among TM individuals to narrow screening disparities. The purpose of this study was to assess the rate of cervical cancer screening among TM individuals following the introduction of self-collected swabbing for hr-HPV DNA testing in comparison to clinician-administered cervical specimen collection.

Methods: Rates of uptake and adherence to cervical cancer screening among TM individuals were assessed before and after the clinical introduction of self-collected swab testing in October 2017. Rates were compared with the rates of cervical cancer screening among cisgender women at a colocated Comprehensive Health Program during the time period of review.

Results: Of the 121 TM patients seen for primary care in the 6-month baseline period before the October 2017 introduction of self-collected swabbing for hr-HPV DNA testing, 30 (25%) had cervical cancer screening documented in the electronic medical record. Following the implementation of self-swabbing, of 193 patients, 98 (51%) had a documented cervical cancer screening, a two-fold increase in the rates of adherence to cervical cancer screening (p<0.001).

Conclusion: Self-collected swab testing for hr-HPV can increase rates of adherence to screening recommendations among an otherwise under-screened population.

Population-based primary HPV mRNA cervical screening compared with cytology screening

Primary HPV screening for cervical cancer by HPV mRNA testing (Aptima) was implemented in January 2017, for women ≥30 through 70 years, in the Region of Skåne, Sweden. HPV positive samples underwent cytology assessment, and women with any degree of abnormal cytology were referred for colposcopy. The aim was to audit the primary HPV screening program, by comparing the cytology results to those of corresponding women (aged ≥30 through 65 years) screened with conventional cytology during 2016. Overall, HPV was detected among 7.0% (4433/63,055) of the women ≥30-70 years in the primary HPV screening program. Among a co-tested (cytology and HPV) subgroup aged 40-42 years (N = 5039), HPV was detected in 100% (28/28) of high-grade squamous intraepithelial lesions (HSIL) and atypical squamous cells of undetermined significance (ASCUS) where HSIL could not be excluded (ASCH) (9/9), and in 80% (4/5) of cases of atypical glandular cells (AGC). Among women ≥30-65 years, the proportion ASCUS or worse (ASCUS+) was similar with cytology (3.52% [2016]) and primary HPV screening (3.70% [2017]). Only the proportion of ASC-H changed by the use of primary HPV screening, from 0.13% (2016) to 0.23% (2017) (p < 0.001). The colposcopy referral rate increased by 54% (3.70 vs 2.41%), when primary HPV screening was introduced. In conclusion, the implemented primary HPV screening approach demonstrated similar prevalence of ASCUS+ cytology as conventional screening. In addition, primary HPV screening decreased cytology assessments by 86% in our screening population of women 30 through 70 years taken into account the co-tested women.

Diagnostic Test Accuracy Review of Cytology for Squamous Intraepithelial Lesion and Squamous Cell Carcinoma of Uterine Cervix

BACKGROUND

Even though cervico-vaginal smears have been used as a primary screening test for cervical carcinoma, the diagnostic accuracy has been controversial. The present study aimed to evaluate the diagnostic accuracy of cytology for squamous intraepithelial lesion (SIL) and squamous cell carcinoma (SqCC) of the uterine cervix through a diagnostic test accuracy (DTA) review.

METHODS

A DTA review was performed using 38 eligible studies that showed concordance between cytology and histology. In the DTA review, sensitivity, specificity, diagnostic odds ratio (OR), and the area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve were calculated.

RESULTS

In the comparison between abnormal cytology and histology, the pooled sensitivity and specificity were 93.9% (95% confidence interval [CI], 93.7%-94.1%) and 77.6% (95% CI, 77.4-77.8%), respectively. The diagnostic OR and AUC on the SROC curve were 8.90 (95% CI, 5.57-14.23) and 0.8148, respectively. High-grade squamous intraepithelial lesion (HSIL) cytology had a higher sensitivity (97.6%; 95% CI, 94.7%-97.8%) for predicting HSIL or worse histology. In the comparison between SqCC identified on cytology and on histological analysis, the pooled sensitivity and specificity, diagnostic OR, and AUC were 92.7% (95% CI, 87.3%-96.3%), 87.5% (95% CI, 87.2%-87.8%), 865.81 (95% CI, 68.61-10,925.12), and 0.9855, respectively. Geographic locations with well-organized screening programs had higher sensitivity than areas with insufficient screening programs.

CONCLUSION

These results indicate that cytology had a higher sensitivity and specificity for detecting SIL and SqCC of the uterine cervix during primary screening.

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.

HPV-FASTER: broadening the scope for prevention of HPV-related cancer

Human papillomavirus (HPV)-related screening technologies and HPV vaccination offer enormous potential for cancer prevention, notably prevention of cervical cancer. The effectiveness of these approaches is, however, suboptimal owing to limited implementation of screening programmes and restricted indications for HPV vaccination. Trials of HPV vaccination in women aged up to 55 years have shown almost 90% protection from cervical precancer caused by HPV16/18 among HPV16/18-DNA-negative women. We propose extending routine vaccination programmes to women of up to 30 years of age (and to the 45-50-year age groups in some settings), paired with at least one HPV-screening test at age 30 years or older. Expanding the indications for HPV vaccination and much greater use of HPV testing in screening programmes has the potential to accelerate the decline in cervical cancer incidence. Such a combined protocol would represent an attractive approach for many health-care systems, in particular, countries in Central and Eastern Europe, Latin America, Asia, and some more-developed parts of Africa. The role of vaccination in women aged >30 years and the optimal number of HPV-screening tests required in vaccinated women remain important research issues. Cost-effectiveness models will help determine the optimal combination of HPV vaccination and screening in public health programmes, and to estimate the effects of such approaches in different populations.

Detection and Typing of Human Papilloma Viruses by Nested Multiplex Polymerase Chain Reaction Assay in Cervical Cancer

Background:

Cervical cancer is the leading cause of death from cancer in under-developed countries. Human papilloma virus (HPV) 16 and 18 are the most prevalent types associated with carcinogenesis in the cervix. Conventional Polymerase Chain Reaction (PCR), type-specific and consensus primer-based PCR followed by sequencing, Restriction Fragment Length Polymorphism (RFLP) or hybridization by specific probes are common methods for HPV detection and typing. In addition, some researchers have developed a multiplex PCR for simultaneous detection and typing of different HPVs.

Objectives:

The aim of the present study was to investigate the prevalence of HPV infection and its types in cervical Squamous Cell Carcinoma (SCC) using the Nested Multiplex PCR (NMPCR) assay.

Patients and Methods:

Sixty-six samples with histologically confirmed SCC were evaluated. Total DNA was isolated by phenol–chloroform extraction and ethanol precipitation. Nested multiplex PCR was performed with first-round PCR by GP-E6/E7 consensus primers for amplification of the genomic DNA of all known mucosal HPV genotypes and second-round PCR by type-specific multiplex PCR primer cocktails.

Results:

Human papilloma virus infection was detected in 78.8% of samples, with the highest prevalence of HPV 16 (60.6%) while concurrent infections with two types was detected in 10.6%.

Conclusions:

The NMPCR assay is more convenient and easy for analysis of results, which is important for fast diagnosis and patient management, in a type-specific manner.

Comparison of the hybrid capture test and polymerase chain reaction in identifying women who have an atypical squamous cell of undetermined significance papanicolaou smear and need colposcopy

OBJECTIVES

The objective of this study was to detect human papillomavirus (HPV) in women with a newly diagnosed atypical squamous cells of undetermined significance (ASCUS) using the hybrid capture (HC) test and the polymerase chain reaction (PCR). We sought to evaluate the accuracy of both tests in identifying women with a concomitant cervical intraepithelial neoplasia (CIN).

MATERIALS AND METHODS

We studied 360 women who had a diagnosis of ASCUS and were referred to the colposcopy clinic. Subjects were between 18 and 50 years, had newly diagnosed ASCUS, had no history of cervical biopsies or treatment, and were not pregnant. A cell sample for HPV testing and colposcopically directed biopsies of lesions were obtained. HPV was detected using the Digene HC and PCR systems (Digene, Silver Spring, MD).

RESULTS

Biopsies showed concomitant CIN in 80 patients (22.2%). Of these, 19 had CIN2 or CIN3. HPV-DNA was detected in 76 of the 360 women (21.1%) using HC and in 166 of 348 women (47.7%) using PCR. The concordance between HC and PCR for detecting HPV was 65%. The sensitivity, specificity, and positive and negative predictive values of HC for detecting CIN were 48%, 86%, 50%, and 85%, respectively. The sensitivity, specificity, and positive and negative predictive values of PCR for detecting CIN were 67%, 58%, 31%, and 86%, respectively. Focusing on CIN2 and CIN3 alone, these values were 79%, 82%, 20%, and 99% for HC, respectively, and 89%, 55%, 10%, and 99% for PCR, respectively.

CONCLUSION

The specificity of HC was higher than the specificity of PCR. For this reason, the HC might be more useful than PCR as a secondary triage method for detecting CIN in women who have incident ASCUS and need colposcopy.

The Triage of Women with ASCUS Cytology Using Human Papillomavirus DNA Testing

OBJECTIVE

Our goal was to determine whether human papillomavirus (HPV) DNA testing is a valuable tool in triage of patients with cytology demonstrating atypical squamous cells of undetermined significance (ASCUS).

METHODS

Our study included a total of 355 women who were referred for evaluation of a Papanicolaou smear with ASCUS diagnosed during routine screening. At the first visit, all patients had colposcopic examinations and HPV DNA testing by Hybrid Capture assay. Patients were evaluated every 4 to 6 months. Follow-up included repeat cytology and colposcopy at each visit; biopsy was performed if indicated. Followup continued for up to 2 years.

RESULTS

Sensitivity, specificity, and positive and negative predictive values of HPV DNA testing in detecting cervical intraepithelial neoplasia grade 2 (CIN2) or CIN3 were 85%, 77%, 12%, and 99%, respectively. The prevalence of oncogenic HPV types was higher in patients younger than age 35 (35% versus 25%) in whom ASCUS-favor dysplasia/ASCUS-not otherwise specified was diagnosed. The presence of oncogenic HPV types equated with a 12.4% risk of biopsy-proven CIN2 and CIN3. The rate of CIN2 and CIN3 was 0.4% in those who tested negative (95% confidence interval, 0-2.1%).

CONCLUSIONS

HPV DNA testing appears to be a valuable tool for triage of women with ASCUS smears. Its high negative predictive value provides needed reassurance for follow-up with only periodic cytology.

Development of a quality framework for models of cervical screening and its application to evaluations of the cost-effectiveness of HPV vaccination in developed countries

BACKGROUND

HPV vaccination has now been introduced in most developed countries, but this has occurred in the context of established cervical cancer screening mechanisms which provide population-level protection against the most common HPV-related cancer. Therefore, estimating the cost-effectiveness of HPV vaccination to further reduce HPV-related disease depends in large part on the estimation of the effectiveness of the cervical screening 'background'. The aim of this study was to systematically review and assess methods for simulating cervical screening in decision analytic models used for evaluation of HPV vaccination.

METHODS

Existing quality frameworks for economic models were extended to develop a specific quality framework for models of cervical screening. This involved domains for model structure, parameterisation (data sources) and validation (consistency). A systematic review of economic evaluations of HPV vaccination was then conducted, and assessment of cervical screening model components was then performed via application of the new quality framework.

RESULTS

Generally, models took into account population-level cervical screening participation, but were inconsistent in their approach to modelling abnormal smear management, diagnostic evaluation and treatment of precancerous disease. There was also considerable variability in the accuracy of modelling clinical pathways and the scope of validation performed for screening-related outcomes, with focus directed towards cervical cancer targets. Only a few models comprehensively validated against observed pre-cancerous abnormalities.

CONCLUSION

Models of HPV vaccination in developed countries can be improved by further attention to the 'background' modelling of secondary protection via cervical screening. The quality framework developed for this review can be used to inform future HPV vaccination evaluations, including evaluations of the cost-effectiveness of male vaccination and next generation HPV vaccines, and to assess models used to evaluate new cervical screening technologies and recommendations.

Methylation of twelve CpGs in human papillomavirus type 16 (HPV16) as an informative biomarker for the triage of women positive for HPV16 infection

An accurate biomarker for the follow-up of women positive for human papillomavirus type 16 (HPV16) DNA may improve the efficiency of cervical cancer prevention. Previously, we analyzed all 113 HPV16 CpGs in cervical cytology samples and discovered differential methylation at different stages of premalignancy. In the current study, we identified a methylation biomarker consisting of a panel of 12 HPV16 CpG sites in the E5, L2, and L1 open reading frames, and tested whether it fulfilled three necessary conditions of a prospective biomarker. A total of 33 cytology samples from North American and West African women with all grades of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC) were analyzed by using DNA bisulfite sequencing. The results showed (i) a highly significant trend for increasing HPV16 biomarker methylation with increasing histologic severity (P < 0.0001), (ii) 100% sensitivity for ICC over a wide range of methylation cutoff scores; 80% detection of CIN3 at cutoff scores up to 39% methylation, and (iii) substantially lower detection of CIN2, from 0% to 71%, depending on the cutoff score. Our results support the prognostic potential of the HPV16 methylation biomarker for the triage to colposcopy of women with HPV16-positive screening tests and, eventually, for the management of women with HPV16-positive CIN2.

Topical imiquimod treatment for human papillomavirus infection in patients with and without cervical/vaginal intraepithelial neoplasia

OBJECTIVE

To evaluate the efficacy and toxicity of topical imiquimod for the treatment of persistent human papillomavirus (HPV) infection in patients with or without cervical/vaginal intraepithelial neoplasia (CIN/VAIN).

METHODS

Patients with persistent HPV infection (≥ 1 year) after a history of treatment for cervical or vaginal neoplasm but normal histology and cytology, abnormal Papanicolaou (Pap) smears without abnormal histology, and untreated histology-documented CIN/VAIN Grade 1/2/3 with HPV-positive testing were recruited. Patients were instructed to apply 250 mg of 5% imiquimod cream intravaginally on consecutive days or at least twice weekly on an outpatient basis for a minimum of 12 doses. A group of age- and previous diagnosis-matched, imiquimod-untreated historical controls (n = 20) were selected. The main outcome measures included HPV DNA detection, cytology, and colposcopy/histology at 6 months after treatment.

RESULTS

A total of 72 patients were eligible for analysis. At a median follow-up of 33.6 months, 37 patients (51.4%) had cytological/histological regression and tested HPV-negative. Six patients (8.3%) had progressive cytology/histology with persistent HPV infections. Of the 72 treated patients, 26 patients who had a normal Pap test but were persistently HPV-positive for at least 1 year had a complete regression rate of 65.4%, which was significantly different from the rate (30%) observed in the untreated historical control (p = 0.036). Six patients with histologically proven CIN2/3 or VAIN2/3 had a complete regression rate of 66.6% (4/6).

CONCLUSIONS

The tolerability of intravaginal self-administered imiquimod is confirmed. Its efficacy in the treatment of women with persistent HPV infection and normal cytology warrants further randomized, controlled trials to determine appropriate dosages and scheduling.

High-risk human papillomavirus genotype detection by electrochemical DNA chip method

High-risk human papillomavirus (HPV) genotypes are the major cause of cervical cancer. Hence, HPV genotype detection is a helpful preventive measure to combat cervical cancer. Recently, several HPV detection methods have been developed, each with different sensitivities and specificities. The objective of this study was to compare HPV high risk genotype detection by an electrochemical DNA chip system, a line probe assay (INNO- LiPA) and sequencing of the L1, E1 regions. A total of 361 cervical smears with different cytological findings were subjected to polymerase chain reaction-sequencing and electrochemical DNA chip assessment. Multiple infections were found in 21.9% (79/361) of the specimens, most prevalently in 20-29-year olds while the highest prevalence of HPV infection was found in the 30-39-year age group. The most prevalent genotype was HPV 16 at 28.2% (138/489) followed by HPV 52 at 9.6% (47/489), with the other types occurring at less than 9.0%. The electrochemical DNA chip results were compared with INNO-LiPA and sequencing (E1 and L1 regions) based on random selection of 273 specimens. The results obtained by the three methods were in agreement except for three cases. Direct sequencing detected only one predominant genotype including low risk HPV genotypes. INNO-LiPA identified multiple infections with various specific genotypes including some unclassified-risk genotypes. The electrochemical DNA chip was highly accurate, suitable for detection of single and multiple infections, allowed rapid detection, was less time-consuming and was easier to perform when compared with the other methods. It is concluded that for clinical and epidemiological studies, all genotyping methods are perfectly suitable and provide comparable results.

Analysis of the codon 72 polymorphism of TP53 and human papillomavirus infection in Iranian patients with prostate cancer

The TP53 gene is one of the most important tumor suppressor genes controlling DNA transcription and cell regulation. Common polymorphisms in p53 gene may play a role in some cancers. Some studies have reported an association between human papillomavirus (HPV) infections and prostate cancer. The aim of this study was to investigate whether the TP53 codon 72 polymorphism and HPV infection are responsible for susceptibility to prostate cancer in Iranian men. The prostate biopsies were taken during surgery from 68 Iranian prostatic cancer patients, and 85 patients with benign prostate hyperplasia. For genotyping of the p53 polymorphism at codon 72, PCRRFLP methods were used and the PCR products were digested with BstU1. An attempt was also made to detect HPV DNA in benign prostate hyperplasia and prostate cancer specimens. Among cancer cases, the distribution of Arg/Arg, Arg/Pro and Pro/Pro genotypes were 26.5%, 45.4%, and 19.1%, respectively. Among patients with benign prostate hyperplasia, the distribution of Arg/Arg, Arg/Pro, and Pro/Pro genotypes were 27%, 53%, and 20%, respectively. The allele frequencies did not differ significantly between prostate cancer and benign prostate hyperplasia samples. Human papillomavirus was detected only in three patients (4.4%; P = 0.71). The results from this study suggest that the TP53 codon 72 polymorphism and HPV infection do not confer susceptibility to prostate cancer in the Iranian population. Larger population-based studies are needed to clarify the relation between prostate carcinoma and p53 polymorphism and HPV infection.

The prevalence and role of human papillomavirus genotypes in primary cervical screening in the northeast of China

Background

Studies have shown that type-specific persistence of high-risk human papillomavirus (HPV) infection contributed significantly to cervical carcinogenesis.

Methods

In this population-based study (on 24041 women), we report on the prevalent genotypes of HPVs and the prevalent genotypes of HPV persistent infection in the northeast of China.

Results

Our results showed that in HPV infected women (45.6% in total), (95% CI, 44.97%–46.23%), 17.35% (95%CI, 16.87%–17.83%) suffered persistent infection. The most common high-risk HPV types in persistent positivity were HPV-16 (18.21%; 95%CI, 17.04%–19.38%), HPV-58 (13.2%; 95%CI, 12.17%–14.23%), HPV-18 (8.66%; 95%CI, 7.81%–9.51%), HPV-52 (7.06%; 95% CI, 6.28%–7.84%) and HPV-33 (6.78%; 95% CI, 6.02%–7.54%). The prevalence of persistent infections with HPV-16,–58, −18, −52 and 33 in cervicitis were lower compared to those in CIN (all P < 0.05). HPV-58, −33 and multiple HPV persistent positivity were significantly associated with older age (all P < 0.05). HPV-18 persistent positivity was significantly associated with adenocarcinoma and lymphatic metastasis (all P < 0.05). HPV-18 persistent positivity was associated with cervical cancer prognosis (P <0.0001). Multivariate analyses showed that HPV-18 persistent positivity, (RR = 1.704, 95%CI = 1.095–2.654, p = 0.028) and lymphatic metastasis (RR = 2.304, 95%CI = 1.354–3.254, P = 0.015) were independent predictors for 3-year survival in cervical cancer.

Conclusions

we provided extensive results of HPV genotype prevalence and distribution in the northeast of China. HPV genotyping is worthwhile to perform because of its independent prognostic value in cervical cancer

HPV-related (pre)malignancies of the female anogenital tract in renal transplant recipients

Renal transplantations (RTs) are performed routinely in many countries. After RT, the administration of lifelong immunosuppressive therapy is required. As a consequence, renal transplant recipients (RTRs) have a high risk to develop virus-associated (pre)malignancies, such as Human papillomavirus (HPV) related anogenital (pre)malignancies. It is known that the majority of the RTRs are infected with HPV and that these women have a 14-fold increased risk of cervical cancer, up to 50-fold of vulvar cancer and up to 100-fold of anal cancer. Often, treatment of these lesions requires concessions and may be suboptimal as radiation therapy and extensive surgery may damage the renal transplant. Therefore, prognosis may be compromised due to inadequately treated malignancies. Especially for these immunocompromised patients prevention is of utmost importance. Yearly cervical cancer screening for RTRs is advised, but appears to be executed poorly. For the future, optimizing screening and prevention of anogenital (pre)malignancies is an important issue for women after RT. This review gives a broad overview of all aspects regarding HPV-related (pre)malignancies of the female anogenital tract in RTRs.

Intradermal injection of PPD as a novel approach of immunotherapy in anogenital warts in pregnant women

Immunotherapy for treatment of recalcitrant warts was used through different modalities including intralesional injection of purified protein derivative (PPD), which is an extract of Mycobacterium tuberculosis, used for testing exposure to tuberculin protein, either from a previous vaccination or from the environment. This method is used to evaluate the efficacy of a new approach of intradermal injection of PPD in the treatment of anogenital warts in pregnant women. A total of 40 pregnant women, aged 20-35 years, and presented with anogenital warts were enrolled in this study. Human papillomavirus (HPV) typing was done using the GP5+/GP6+ PCR assay. The patients were treated with weekly injections of PPD given intradermally in the forearms, and evaluated for the response regularly. HPV type-6 was the predominant genotype (67.5%). Overall, the improvement in this study was 85% and was related to the extent of tuberculin reactivity. Nineteen (47.5%) patients demonstrated complete clearance, 15 (37.5%) had partial response, and three (7.5%) had minimal response. Three (7.5%) cases did not respond to treatment. Side effects were minimal and insignificant. Treatment of anogenital warts in pregnant women with intradermal injection of PPD was found to be a unique, safe, and effective modality of immunotherapy.

False-positive Human Papillomavirus DNA tests in cervical screening: it is all in a definition

AIM

Based on data from randomised controlled trials (RCT) on primary cervical screening, it has been reported that the problem of more frequent false-positive tests in Human Papillomavirus (HPV) DNA screening compared to cytology could be overcome. However, these reports predominantly operated with a narrow definition of a (false-)positive test. The aim of this paper was to illustrate how the narrow definition affected the measured adverse effects of HPV DNA screening compared with cytology screening.

METHODS

In the European RCT data, we measured the impact of the narrow definition of a positive screening test on the published relative positive predictive values (PPV), an indicator of the relative frequency of false-positive screening tests.

RESULTS

Using the trialists' definitions of positive screening tests, HPV screening combined with cytology triage had relative PPVs of 0.87 (95% confidence interval (CI): 0.60-1.26) for ≥ CIN3 based on Swedish RCT data, and 0.78 (0.52-1.16) for ≥ CIN2 in the Italian Phase 1 RCT (25-34 years). These PPVs changed to 0.44 (0.30-0.64) and 0.51 (0.33-0.79), respectively, when all positive HPV or cytology screening tests were accounted for. In the Finnish RCT data, HPV screening using the cut-off point of ≥ 10 pg/ml had a relative PPV of 0.27 (0.15-0.50) for ≥ CIN3, which changed to 1.84 (0.99-3.41).

CONCLUSION

The relative PPV was incorrectly estimated in six out of seven studies. In three of those six studies, the relative PPV changed significantly after inclusion of the previously erroneously excluded false-positive HPV or cytology tests.

Cost-effectiveness of different human papillomavirus vaccines in Singapore

Background

Human papillomavirus (HPV) vaccines are widely available and there have been studies exploring their potential clinical impact and cost-effectiveness. However, few studies have compared the cost-effectiveness among the 2 main vaccines available - a bivalent vaccine against HPV 16/18, and a quadrivalent vaccine against 6/11/16/18. We explore the cost-effectiveness of these two HPV vaccines in tropical Singapore.

Methods

We developed a Markov state-transition model to represent the natural history of cervical cancer to predict HPV infection, cancer incidence, mortality, and costs. Cytologic screening and treatment of different outcomes of HPV infection were incorporated. Vaccination was provided to a cohort of 12-year old females in Singapore, followed up until death. Based on available vaccines on the market, the bivalent vaccine had increased effectiveness against a wider range of HPV types, while the quadrivalent vaccine had effectiveness against genital warts. Incremental cost-effectiveness ratios (ICER) compared vaccination to no-vaccination, and between the two vaccines. Sensitivity analyses explored differences in vaccine effectiveness and uptake, and other key input parameters.

Results

For the no vaccination scenario, 229 cervical cancer cases occurred over the cohort's lifetime. The total discounted cost per individual due to HPV infection was SGD$275 with 28.54 discounted life-years. With 100% vaccine coverage, the quadrivalent vaccine reduced cancers by 176, and had an ICER of SGD$12,866 per life-year saved. For the bivalent vaccine, 197 cancers were prevented with an ICER of $12,827 per life-year saved. Comparing the bivalent to the quadrivalent vaccine, the ICER was $12,488 per life-year saved. However, the cost per QALY saved for the quadrivalent vaccine compared to no vaccine was $9,071, while it was $10,392 for the bivalent vaccine, with the quadrivalent vaccine dominating the bivalent vaccine due to the additional QALY effect from reduction in genital warts. The overall outcomes were most sensitive to vaccine cost and coverage.

Conclusion

HPV vaccination is a cost-effective strategy, and should be considered a possible strategy to reduce the impact of HPV infection.

Comparison of the DiagCor GenoFlow Human Papillomavirus Array Test and Roche Linear Array HPV Genotyping Test

Persistent infection of high-risk (HR) human papillomavirus (HPV) infection has been widely associated with cervical cancer. Monitoring HPV infection is therefore an important step against cervical cancer development. The DiagCor GenoFlow Human Papillomavirus Array Test (GenoFlow) is a novel HPV test based on PCR and "Flow-through" hybridization that can identify 33 HPV subtypes in 3 hours. In the present study, the GenoFlow Test was evaluated by comparing the genotyping results of 100 samples with Roche Linear Array HPV Genotyping Test (LA). The tests showed good agreement in detection of HPV-positive samples (concordance rate=95%, Cohen's Kappa=0.896), with good agreement in detection of HR HPVs (Cohen's Kappa=0.876). The GenoFlow Test showed high sensitivity (95%), high specificity (95%), low false positive rate (3.33%) and low false negative rate (7.50%). In conclusion, the novel GenoFlow Test showed comparable clinical performance to LA test, and offers advantages of reduction in turnaround time and manpower.

Cost-effectiveness of human papillomavirus vaccination for prevention of cervical cancer in Taiwan

BACKGROUND

Human papillomavirus (HPV) infection has been shown to be a major risk factor for cervical cancer. Vaccines against HPV-16 and HPV-18 are highly effective in preventing type-specific HPV infections and related cervical lesions. There is, however, limited data available describing the health and economic impacts of HPV vaccination in Taiwan. The objective of this study was to assess the cost-effectiveness of prophylactic HPV vaccination for the prevention of cervical cancer in Taiwan.

METHODS

We developed a Markov model to compare the health and economic outcomes of vaccinating preadolescent girls (at the age of 12 years) for the prevention of cervical cancer with current practice, including cervical cytological screening. Data were synthesized from published papers or reports, and whenever possible, those specific to Taiwan were used. Sensitivity analyses were performed to account for important uncertainties and different vaccination scenarios.

RESULTS

Under the assumption that the HPV vaccine could provide lifelong protection, the massive vaccination among preadolescent girls in Taiwan would lead to reduction in 73.3% of the total incident cervical cancer cases and would result in a life expectancy gain of 4.9 days or 8.7 quality-adjusted life days at a cost of US$324 as compared to the current practice. The incremental cost-effectiveness ratio (ICER) was US$23,939 per life year gained or US$13,674 per quality-adjusted life year (QALY) gained given the discount rate of 3%. Sensitivity analyses showed that this ICER would remain below US$30,000 per QALY under most conditions, even when vaccine efficacy was suboptimal or when vaccine-induced immunity required booster shots every 13 years.

CONCLUSIONS

Although gains in life expectancy may be modest at the individual level, the results indicate that prophylactic HPV vaccination of preadolescent girls in Taiwan would result in substantial population benefits with a favorable cost-effectiveness ratio. Nevertheless, we should not overlook the urgency to improve the compliance rate of cervical screening, particularly for older individuals.

Evaluation of a newly developed GenoArray human papillomavirus (HPV) genotyping assay and comparison with the Roche Linear Array HPV genotyping assay

Persistent infection with high-risk types of human papillomavirus (HPV) is a necessary step in the development of cervical cancer. The incorporation of HPV detection into cervical screening programs may improve the ability to identify women at risk of cervical cancer. We recently evaluated the performance characteristics of a newly developed HPV detection assay, the GenoArray (GA) genotyping assay, for the detection of HPV infections by comparing it with the commercial Roche Linear Array (LA) HPV genotyping assay. The GA assay has an analytical sensitivity for the detection of HPV types 16 (HPV-16) and HPV-18 of as few as 10 to 50 copies, and its reproducibility is adequate. The GA and LA assays showed no significant difference in the rates of detection of genotypes detected by both HPV genotyping assays and oncogenic genotypes, and the interassay agreement was excellent. The GA and LA assays revealed either concordant or compatible genotyping results for 97.5% of the samples and discordant results for only eight (2.5%) samples. Compatible results were also observed for the detection of single or multiple HPV infections and the detection of most of the genotypes. The GA assay also demonstrated good clinical performance characteristics when the comparisons were carried out with clinical subgroups of samples from patients with normal cytologies, low-grade or high-grade squamous intraepithelial lesions, and cancers. Therefore, the GA assay appears to be highly sensitive and specific for the genotyping of HPV. It has the advantage that it specifically detects HPV-52, which overcomes a limitation of the LA assay, and hence, it has potential value for use for genotyping, especially in regions where HPV-52 has a high prevalence.

History of the use of HPV testing in cervical screening and in the management of abnormal cervical screening results

Twenty years have passed since the first studies using human papillomavirus (HPV) testing began in clinical settings. At that time controversy regarding the role of HPV in cervical carcinogenesis still divided the scientific world. Epidemiological and natural history studies on HPV and cervical cancer in the ensuing two decades secured the necessary role of high-risk (carcinogenic) HPV in the genesis of cervical cancer, providing the rationale for testing for its cause. Subsequently, cross sectional studies and large randomized trials have provided clinical validation for high-risk HPV testing in triage of atypical squamous cells of undetermined significance (ASC-US), in postcolposcopy management of women referred for ASC-US, atypical squamous cells "cannot rule out high grade" (ASC-H), atypical glandular cells "not otherwise specified" (AGC NOS) and low grade squamous intraepithelial lesion (LSIL) and not found to have cervical intraepithelial neoplasia (CIN) 2+ or adenocarcinoma in situ (AIS) at initial colposcopy, in post-treatment of CIN 2+ surveillance, and in cotesting with the Papanicolaou (Pap) test of women age 30 and over. This is the story of the road traveled that brought the clinical use of HPV testing from its genesis only a few years after Dr. zur Hausen's discovery to its present eminent role in both primary cervical cancer screening and abnormal Pap management.

Comparison of the hybrid capture II assay with the human papillomavirus DNA chip test for the detection of high-grade cervical lesions

Cervical intraepithelial neoplasia (CIN) 2 is used as the threshold for treatment decisions. This study was conducted to evaluate the clinical efficacy of the Hybrid Capture II assay (HC2) and the human papillomavirus (HPV) DNA chip test (HDC) for detecting HPV in high-grade cervical lesions CIN2 or greater, including adenocarcinoma (CIN2+). Seven hundred forty-one women with abnormal cervical cytology were evaluated with the HC2, the HDC, and histological assessment of the cervix. The overall agreement of the 2 HPV tests was 88.8% (kappa value, 0.61). Of 615 high-risk HPV-positive specimens by the HC2, 571 (92.8%) were HDC-positive. Both tests were performed similarly on CIN2+ samples; the sensitivities of the HC2 and HDC as predictors of CIN2+ were 93.4 and 92.6%, respectively. In 83 cases of discrepancies between the HC2 and HDC, genotyping of 39 HC2-negative/HDC-positive cases revealed 13 HPV-53, 8 HPV-58, 7 HPV-16, 6 HPV-18, 2 HPV-68, 1 HPV-31, 1 HPV-45, and 1 HPV-66. In 515 patients with CIN2+, HPV-16 (45.0%) was the most common type; the next most common types were HPV-58 (20.8%), HPV-18 (16.1%), HPV-31 (6.6%), and HPV-33 (6.6%). Human papillomavirus types 16, 58, and 18 were more likely associated with CIN2+ (P < 0.05). In conclusion, the HDC is a reliable diagnostic tool for the detection of CIN2+. In addition, the HDC provides useful information regarding viral genotypes.

Estimating the Long-Term Clinical Impact of Cervical Cancer Vaccination in Taiwan

The high burden of human papillomavirus (HPV) infection and subsequent cervical cancer in the presence of screening in Taiwan suggests the need for further prevention strategies. Epidemiology and screening practices vary considerably between countries, and specific analyses are required to estimate the impact of HPV vaccination. This study adapted a computer-based health economic model to Taiwan to project the clinical impact of the introduction of a prophylactic vaccine against persistent HPV 16/18 infection on cervical disease. A Markov model based on the natural history of HPV and cervical cancer was developed to simulate transitions between health states (normal, HPV, cervical intraepithelial neoplasia [CIN] stages I to III, cervical cancer stages I to IV, and death) in the presence of screening. The model was calibrated to Taiwan epidemiological end points including age-specific HPV prevalence, prevalence of CIN lesions, and predicted cervical cancer incidence and mortality. Taiwanese screening and treatment practices were modeled, and published clinical trial data were used to estimate vaccine efficacy. With 100% vaccine coverage in a 13-year-old cohort of females, there is estimated to be a 71% reduction in cervical cancer cases and deaths due to all HPV types and substantial reductions in the prevalence of precancerous lesions and screening outcomes. Removing the risk of HPV infection of a large proportion of Taiwanese females, with a high underlying cervical cancer incidence rate, would be expected to have dramatic effects on the health care system and mortality in Taiwan.

Age-specific prevalence of infection with human papillomavirus in females: a global review

PURPOSE

Global data on age-specific prevalence of human papillomavirus (HPV) infection overall, and for high-risk HPV types 16 and 18, are essential for the future implementation of HPV prophylactic vaccines for cervical cancer prevention.

METHODS

A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in women. Studies with clear descriptions of polymerase chain reaction or hybrid capture detection assays were included.

RESULTS

A total of 346,160 women were included in 375 studies. Of 134 studies with age-stratified HPV prevalence data (116 low sexual risk populations, 18 high sexual risk populations), over 50% were from Europe and the Middle East (38%) and North America (19%), with smaller proportions from Asia and Australia (21%), Central and South America (11%), and Africa (10%). Across all geographical regions, data on HPV prevalence were generally limited to women over 18 years of age. Consistently across studies, HPV infection prevalence decreased with increasing age from a peak prevalence in younger women (< or =25 years of age). In middle-aged women (35-50 years), maximum HPV prevalence differed across geographical regions: Africa (approximately 20%), Asia/Australia (approximately 15%), Central and South America (approximately 20%), North America (approximately 20%), Southern Europe/Middle East (approximately 15%), and Northern Europe (approximately 15%). Inconsistent trends in HPV prevalence by age were noted in older women, with a decrease or plateau of HPV prevalence in older ages in most studies, whereas others showed an increase of HPV prevalence in older ages. Similar trends of HPV 16 and/or 18 prevalence by age were noted among 12 populations with available data.

DISCUSSION

Genital HPV infection in women is predominantly acquired in adolescence, and peak prevalence in middle-aged women appears to differ across geographical regions. Worldwide variations in HPV prevalence across age appear to largely reflect differences in sexual behavior across geographical regions. Further studies of HPV prevalence in adolescents are needed for all geographic regions.

[Natural history of precursor lesions of cervical cancer]

Precursor lesions of invasive cancer of uterine cervix begin at the squamocolumnar junction. On this zone in permanent transformation, human papillomavirus (HPV) gives condylomatous lesions, pure or associated with neoplasic transformation of the epithelium. For 50 years, various histological classifications have been proposed. First, four groups have been designed: light, moderate, severe dysplasia and in situ carcinoma. Secondly, Richart proposed the cervix intraepithelial neoplasia classification (CIN) with three grades (1 to 3) according to their severity. Progression from CIN 1 to CIN 3 and invasive carcinoma is admitted and is consistent with the concept of lesional continuum. However, because of the elevated rate of spontaneous regression of CIN 1, it is probably a lesion of very low potential aggressivity and its role as a precursor is uncertain. Now two groups of different evolutivity are currently considered: low grade and high grade lesions. The last one's, at the opposite of the first, are monoclonal, have major epithelial abnormalities with sometimes abnormal mitoses and are frequently aneuploid. Aggressivity depends on the persistence of HR HPV more than on progressive morphologic transformation. By integrating in-host genoma, it induces modifications on cellular cycle proteins. Revelation by immunohistochemistry brings help to diagnosis of high grade lesions when traditional morphology is ambiguous.

Results at recruitment from a randomized controlled trial comparing human papillomavirus testing alone with conventional cytology as the primary cervical cancer screening test

BACKGROUND

In the first recruitment phase of a randomized trial of cervical cancer screening methods (New Technologies for Cervical Cancer Screening [NTCC] study), we compared screening with conventional cytology with screening by human papillomavirus (HPV) testing in combination with liquid-based cytology. HPV-positive women were directly referred to colposcopy if aged 35 or older; if younger, they were retested after 1 year.

METHODS

In the second recruitment phase of NTCC, we randomly assigned women to conventional cytology (n = 24,661) with referral to colposcopy if cytology indicated atypical squamous cells of undetermined significance or more severe abnormality or to testing for high-risk HPV DNA alone by Hybrid Capture 2 (n = 24,535) with referral to colposcopy if the test was positive at a concentration of HPV DNA 1 pg/mL or greater. For the main endpoint of the study, histologic detection of cervical intraepithelial neoplasia of grade 2 or more (CIN2+), we calculated and compared sensitivity and positive predictive value (PPV) of the two screening methods using HPV DNA cutoffs of 1 pg/mL and 2 pg/mL. All statistical tests were two-sided.

RESULTS

For women aged 35-60 years, the relative sensitivity of HPV testing for detection of CIN2+ at a cutoff of 1 pg/mL vs conventional cytology was 1.92 (95% CI = 1.28 to 2.87) and the relative PPV was 0.80 (95% CI = 0.55 to 1.18). At a cutoff of 2 pg/mL HPV DNA, the relative sensitivity was 1.81 (95% CI = 1.20 to 2.72) and the relative PPV was 0.99 (95% CI = 0.67 to 1.46). In this age group, there was no evidence of heterogeneity between study phases. Among women aged 25-34 years, the relative sensitivity for detection of CIN2+ of HPV testing at a cutoff of 1 pg/mL vs cytology was 3.50 (95% CI = 2.11 to 5.82), statistically significantly larger (P = .019) than that observed in phase 1 at this age (1.58; 95% CI = 1.03 to 2.44).

CONCLUSIONS

For women aged 35-60 years, HPV testing with a cutoff of 2 pg/mL achieves a substantial gain in sensitivity over cytology with only a small reduction in PPV. Among women aged 25-34 years, the large relative sensitivity of HPV testing compared with conventional cytology and the difference between relative sensitivity during phases 1 and 2 suggests that there is frequent regression of CIN2+ that are detected by direct referral of younger HPV-positive women to colposcopy. Thus, triage test or repeat testing is needed if HPV is to be used for primary testing in this context.

Genotyping of human papillomaviruses by a novel one-step typing method with multiplex PCR and clinical applications

We describe here a rapid, high-throughput genotyping procedure that allows the simultaneous detection of 16 high- and low-risk genital human papillomavirus (HPV) types by multiplex PCR in a single reaction tube. Multiplex PCR is based on the amplification of HPV DNA by sets of HPV genotype-specific primers, and the genotypes of HPV are visually identified by the sizes of amplicons after they are separated by capillary electrophoresis. The procedure does not include a hybridization step with HPV-specific probes and is rapid and labor-saving. We detected all 16 HPV genotypes (types 16, 58, 52, 51, 56, 31, 18, 39, 66, 59, 6, 33, 30, 35, 45, and 11) with a high sensitivity and a high degree of reproducibility. By using this newly developed method, we conducted a pilot study to examine the correlation between the prevalence and genotype distributions of HPV and the cytological group classifications for 547 cervical samples. Compared with the group of samples considered normal (14.7%), there was a significant increase in the prevalence of HPV in women with atypical squamous cells of unknown significance (61.3%), low-grade intraepithelial lesions (75.8%), and high-grade intraepithelial lesions (HSILs) (82.2%). The prevalence and distribution of type 58 were correlated with cytological malignancies, with the highest prevalence in women with HSILs. In conclusion, the novel multiplex PCR method described appears to be highly suitable not only for the screening of cervical cancer precursor lesions but also for the characterization of genotype distributions in large-scale epidemiological studies and HPV vaccination trials.