Cervical HPV infection and neoplasia in a large population-based prospective study: the Manchester cohort

Pathology and epidemiology of HPV infection in females

Human papillomaviruses (HPVs) are a large family of small double-stranded DNA viruses that infect squamous epithelia. It has been established that infection with specific HPV types is a contributing factor to different types of anogenital cancer, including vulval, vaginal, anal, penile, and head and neck cancers. Approximately 4% of all cancers are associated with HPV. HPV infection is the major cause of cervical cancer and genital warts. Genital HPV infections are very common, are sexually transmitted, and have a peak prevalence between ages 18 and 30. Most of these infections clear spontaneously, but in 10-20% of women, these infections remain persistent and are at risk of progression to grade 2/3 cervical intraepithelial neoplasm (CIN) and eventually to invasive cancer of the cervix (ICC). CINs are genetically unstable lesions with a 30-40% risk of progression to ICC. If left untreated, they form a spectrum of increasing cytological atypia, ranging from low-grade CIN1 to high-grade CIN3; the latter are caused almost exclusively by high-risk HPVs, HPV 16 and 18. Infection with HPV requires a microabrasion in the genital epithelium. The oncogenic properties of high-risk HPV reside in the E6 and E7 genes, which if inappropriately expressed in dividing cells deregulate cell division and differentiation. HPV DNA testing has been shown consistently to be superior to cytology in terms of sensitivity and positive predictive value and will become a major tool in cervical cancer screening, at least in the developed countries.

HPV type-specific prevalence using a urine assay in unvaccinated male and female 11- to 18-year olds in Scotland

BACKGROUND

We conducted a baseline prevalence survey of unvaccinated 11- to 18-year olds to inform effectiveness studies for the new human papillomavirus (HPV) immunisation programme in Scotland.

METHODS

Participants were recruited from schools and colleges and invited to provide demographic data and an anonymous urine sample for type-specific HPV testing.

RESULTS

Among females aged 11-14 years, the weighted prevalence was 1.1% overall; 0.9% for high-risk types and no infections were associated with types 16 and 18. Among 15- to 18-year old females, the weighted prevalence was 15.2% overall; 12.6% for high-risk types and 6.5% for types 16 and 18. Among females aged 16-18 years, infection was more frequently associated with attending college and rural schools, and showed a trend towards increasing prevalence with increasing social deprivation (P=0.045). Among males aged 11-14 years, the weighted prevalence was 1.4% overall; 1.0% for high-risk types and 0.7% for types 16 and 18. Among 15- to 18-year old males, the weighted prevalence was 3.9% overall; 2.4% for high-risk types and 0.7% for types 16 and 18.

CONCLUSIONS

Human Papillomavirus prevalence is low among 11- to 14-year olds, which includes the age group targeted for routine vaccination. The prevalence in males and correlation with deprivation require further investigation.

The role of optimal control in assessing the most cost-effective implementation of a vaccination programme: HPV as a case study

Vaccination against the human papillomavirus (HPV) is a recent development in the UK. This paper uses an optimal control model to explore how best to target vaccination. We find that the vaccination of sexually active individuals has a greater impact on disease control than the vaccination of sexually non-active individuals. Extending the model to include male vaccination, we find that including males in a vaccination strategy is cost-effective. We compare the optimal control solution to that from a constant control model and show that the optimal control model is more efficient at forcing the system to a disease-controlled steady state.

Olfactomedin 4 is a marker for progression of cervical neoplasia

INTRODUCTION

Olfactomedin 4 (OLFM4) is expressed in gastrointestinal cancers and related to progression and differentiation of these malignancies. However, whether OLFM4 contributes to tumorigenesis of other tissues has not been thoroughly investigated. The purpose of the study was to investigate OLFM4 expression in cervical epithelium and its association with progression of cervical neoplasia and differentiation of cervical carcinomas.

METHODS

Immunohistochemistry and real-time reverse transcription-polymerase chain reaction were used to evaluate the expression and distribution of OLFM4 in cervical intraepithelial neoplasia (CIN) and invasive squamous cell carcinomas (ISCCs).

RESULTS

The overall positive OLFM4 staining levels in normal cervical epithelia, CIN I, CIN II, CIN III, and ISCCs are 22.0%, 94.2%, 93.7%, 94.6%, and 96.7%, respectively. The intensity of OLFM4 staining was enhanced according to increased pathologic grade of cervical squamous intraepithelial lesion. The immunoreactivity to OLFM4 was stronger in well-differentiated ISCCs than in poorly differentiated ISCCs.

CONCLUSIONS

Olfactomedin 4 expression has been associated with progression of CIN and differentiation of cervical cancer. The results provide new evidence that OLFM4 plays an important role in tumorigenesis in the female reproductive tract.

The importance of social norms for uptake of catch-up human papillomavirus vaccination in young women

Background Human papillomavirus (HPV) is the cause of almost all cases of cervical cancer. The current UK government immunisation program includes free routine HPV vaccination of girls aged 12–13, with a catch-up vaccination program for 13–18-year-old girls. The aim of this study was to identify correlates of intended and actual uptake of catch-up HPV vaccination. Methods: An online questionnaire was completed by 591 young women aged 16–20. Results: Of the 350 women who had been offered catch-up HPV vaccination, 90.6% had accepted. In multivariate analyses, vaccine uptake was significantly correlated with subjective norms more supportive of HPV vaccination, and greater uptake of other childhood vaccinations (χ2(3) = 39.34, P < 0.01; 91.1% correctly classified; Nagelkerke pseudo-r2 = 0.23). Among the 241 women aged 16–20 who had not been offered HPV vaccination, the average intention was 3.70 on a five-point scale. Multivariate analyses revealed four significant independent predictors of stronger intentions to accept vaccination: subjective norms more supportive of HPV vaccination, greater worry about sexually transmissible infections, greater support for young people’s sexual health services and greater support for childhood vaccination (F(4,236) = 18.67, P < 0.01; adjusted r2 = 0.23). Young women rated television advertisements, educational programs and television soaps as the most effective ways to encourage uptake of HPV vaccination. Conclusions: Uptake of HPV vaccination may be increased if interventions use appropriate media to promote social norms supportive of HPV vaccination.

The Prevention of Cervical Cancer in Africa

In this article we aim to draw attention to the burden of cervical cancer in Africa for reproductive health and review strategies for prevention, including appropriate noncytology-based cervical screening and prophylactic human papillomavirus vaccination. We consider the heavy burden of disease attributable to human papillomavirus infection borne by developing countries, particularly in Africa. Following identification of the human papillomavirus as the infectious etiological agent and elucidation of the long natural history of cervical neoplasia, cervical cancer is now one of the most preventable of all cancers. Opportunities for primary prevention by prophylactic vaccination and secondary prevention by appropriate cervical screening are discussed, together with the importance of population coverage. Qualitative work on attitudes towards cervical cancer prevention, education needs, the creation of an environment for informed choice and uptake are essential aspects of effective prevention programs. Cervical cancer poses a huge health burden in Africa. It is a disease that is eminently preventable given political will, the availability of affordable vaccines, appropriate cervical screening and access to cheap, point-of-care human papillomavirus testing. There are a number of unanswered questions for the prevention of cervical cancer and a need for demonstration projects to address these and further develop prevention strategies.

Unresolved questions concerning human papillomavirus infection and transmission: a modelling perspective

Mathematical transmission models are widely used to forecast the potential impact of interventions such as vaccination and to inform the development of health policy. Effective vaccines are now available for the prevention of cervical cancer and other diseases attributable to human papillomavirus (HPV). Considerable uncertainties remain regarding the characterisation of HPV infection and its sequelae, infectivity, and both vaccine-conferred and naturally-acquired immunity. In this review, we discuss the key knowledge gaps that impact on our ability to develop accurate models of HPV transmission and vaccination.

HPV - immune response to infection and vaccination

HPV infection in the genital tract is common in young sexually active individuals, the majority of whom clear the infection without overt clinical disease. However most of those who develop benign lesions eventually mount an effective cell mediated immune (CMI) response and the lesions regress.

Failure to develop effective CMI to clear or control infection results in persistent infection and, in the case of the oncogenic HPVs, an increased probability of progression to CIN3 and invasive carcinoma. The prolonged duration of infection associated with HPV seems to be associated with effective evasion of innate immunity thus delaying the activation of adaptive immunity.

Natural infections in animals show that neutralising antibody to the virus coat protein L1 is protective suggesting that this would be an effective prophylactic vaccine strategy. The current prophylactic HPV VLP vaccines are delivered i.m. circumventing the intra-epithelial immune evasion strategies. These vaccines generate high levels of antibody and both serological and B cell memory as evidenced by persistence of antibody and robust recall responses. However there is no immune correlate - no antibody level that correlates with protection. Recent data on how HPV infects basal epithelial cells and how antibody can prevent this provides a mechanistic explanation for the effectiveness of HPV VLP vaccines.

Long-term absolute risk of cervical intraepithelial neoplasia grade 3 or worse following human papillomavirus infection: role of persistence

BACKGROUND

Infection with high-risk human papillomavirus (HPV) is the main cause of high-grade cervical intraepithelial neoplasia (CIN) and cancer. It has been suggested that information about high-risk HPV type-specific infection might make cervical cancer screening more effective. Persistent HPV infection could also be a useful screening marker. We estimated the long-term risk of high-grade CIN after one-time detection of high-risk HPV DNA and after persistent infection with individual high-risk HPV types.

METHODS

A cohort of 8656 women from the general population of Denmark was examined twice, 2 years apart (first study examination: May 15, 1991, to January 31, 1993; second study examination: October 1, 1993, to January 31, 1995). The women underwent a gynecological examination and cervical cytology and had swabs taken for HPV DNA analysis by the Hybrid Capture 2 and line probe assays. The women were followed up through the nationwide Danish Pathology Data Bank for cervical neoplasia for up to 13.4 years. The absolute risk of developing cervical lesions before a given time was estimated as a function of time.

RESULTS

For women with normal cytological findings who were concurrently HPV16 DNA positive at the second examination, the estimated probability of developing CIN grade 3 (CIN3) or worse within 12 years of follow-up was 26.7% (95% confidence interval [CI] = 21.1% to 31.8%). The corresponding risks among those infected with HPV18 was 19.1% (95% CI = 10.4% to 27.3%), with HPV31 was 14.3% (95% CI = 9.1% to 19.4%), and with HPV33 was 14.9% (95% CI = 7.9% to 21.1%). The absolute risk of CIN3 or worse after infection with high-risk HPV types other than HPV16, HPV18, HPV31, or HPV33 was 6.0% (95% CI = 3.8% to 8.3%). The estimated absolute risk for CIN3 or cancer within 12 years of the second examination among women who were HPV16 DNA positive at both examinations was 47.4% (95% CI = 34.9% to 57.5%); by contrast, the risk of CIN3 or worse following a negative Hybrid Capture 2 test was 3.0% (95% CI = 2.5% to 3.5%).

CONCLUSION

HPV16, HPV18, HPV31, and HPV33 infection and especially HPV16 persistence were associated with high absolute risks for progression to high-grade cervical lesions. The results indicate the potential value of genotyping in cervical cancer screening. Given that HPV DNA-negative women retained their low risk of CIN3 or worse for many years, frequent screening of these women may be unnecessary.

Multi-site study of HPV type-specific prevalence in women with cervical cancer, intraepithelial neoplasia and normal cytology, in England

BACKGROUND

Knowledge of the prevalence of type-specific human papillomavirus (HPV) infections is necessary to predict the expected, and to monitor the actual, impact of HPV immunisation and to design effective screening strategies for vaccinated populations.

METHODS

Residual specimens of cervical cytology (N=4719), CIN3/CGIN and cervical cancer biopsies (N=1515) were obtained from sites throughout England, anonymised and tested for HPV DNA using the Linear Array typing system (Roche).

RESULTS

The prevalence of HPV 16 and/or 18 (with or without another high-risk (HR) type) was 76% in squamous cell carcinomas, 82% in adeno/adenosquamous carcinomas and 63% and 91% in CIN3 and CGIN, respectively. Of all HR HPV-infected women undergoing cytology, non-vaccine HPV types only were found in over 60% of those with mild dyskaryosis or below, and in <20% of those with cancer. In women of all ages undergoing screening, HR HPV prevalence was 16% and HPV 16 and/or 18 prevalence was 5%.

CONCLUSION

Pre-immunisation, high-grade cervical disease in England was predominantly associated with HPV 16 and/or 18, which promises a high impact from HPV immunisation in due course. Second-generation vaccines and screening strategies need to consider the best ways to detect and prevent disease due to the remaining HR HPV types.

Vaccination against human papilloma virus (HPV): epidemiological evidence of HPV in non-genital cancers

Recently, the vaccine against human papillomavirus (HPV) was introduced in the national vaccination programmes of several countries worldwide. The established association between HPV and the progression of cervical neoplasia provides evidence of the expected protection of the vaccine against cervical cancer. During the last two decades several studies have also examined the possible involvement of HPV in non-genital cancers and have proposed the presence of HPV in oesophageal, laryngeal, oropharyngeal, lung, urothelial, breast and colon cancers. The possible involvement of HPV in these types of cancer would necessitate the introduction of the vaccine in both boys and girls. However, the role of HPV in the pathogenesis of these types of cancer has yet to be proven. Moreover, the controversial evidence of the possible impact of the vaccination against HPV in the prevention of non-genital cancers needs to be further evaluated. In this review, we present an overview of the existing epidemiological evidence regarding the detection of HPV in non-genital cancers.

A 7.5-year prospective study of longer than 18 months type-specific human papillomavirus persistence in a routine cytology-based cervical screening population of about 31,000 women in West Germany

The objective of this study was to analyse the prevalence, infection pattern, duration and outcome of long-term, type-specific, persistent human papillomavirus (HPV) infections in a routine cytology-based cervical screening population of West German women followed up for 7.5 years. From a screening population of 31,000 women, a strictly selected cohort of 100 patients with > or =18-month persistent, type-specific HPV infection were prospectively followed up for a mean of 35.52 months (+/-13.0). HPV type prevalence and odds ratios for regression, progression and steady state were analysed, as well as the influence of age and HPV coinfection on outcome. Altogether, 21 different genotypes were detected. Seventy-two percent of women were infected with high-risk HPVs, 24% with low-risk and 4% with unknown risk HPV types; 44% of cases had coinfections with multiple HPV types. The risk of progression in low-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions was the highest for infections with high-risk HPVs [odds ratio: 2.2 (0.79-6.11, 95% confidence interval)], whereas cases with low-risk and unknown risk HPVs tended to regress or remained unchanged during follow-up. The mean duration of infections showed considerable variation among the different HPV types and risk groups detected and ranged between 19.7 and 54.3 months. Age was not significantly associated with disease progression and infection duration, and histology had a poor sensitivity for detecting high-grade dysplasia. In conclusion, detecting long-term persistent HPV infections by genotyping may help to identify women with cervical intraepithelial lesions who are at lower and higher risk of developing high-grade precancer and cancer. This may influence future screening strategies and therapy decisions.

Prevalence and distribution of human papillomavirus types in cervical cancer, squamous intraepithelial lesions, and with no intraepithelial lesions in women from Southern Mexico

OBJECTIVE

This study was to establish the frequency of HPV infection and which HPV types are circulating in women with cervical cancer (CC), with squamous intraepithelial lesions (SIL), and with no intraepithelial lesion (non-IL) from the State of Guerrero in Southern Mexico. Additionally, we investigated the frequency and distribution of HPV 16 intratypic variants found in this population.

METHODS

This cross-sectional study was conducted in 4150 women who attended five public health centers seeking cytological screening or for gynecological complaints. Pap smears or biopsies, as appropriate, were obtained for cytological and/or histological diagnosis. HPV detection was done by MY09/11 and GP5+/GP6+ PCR systems and typing by restriction fragment length polymorphism or DNA sequencing. HPV 16 variants were also analyzed.

RESULTS

HPV was found in 100% of CC, 83.5% in HSIL, 94.5% in LSIL, and 40.9% in non-IL. HR-HPV was the most frequent in all groups. HPV 16 was the most commonly identified HPV genotype in CC and HSIL. HPV 33 was the most frequent in LSIL and non-IL. The highest HPV prevalence was found in the youngest women, HR-HPV and HPV 16 were more frequent in women less than 25 years and more than 55 years of age. The HPV 16 variants E, AA-a and AA-c were found, AA-c was found only in CC.

CONCLUSION

This study contributes to the knowledge of regional prevalence of HPV types in the whole spectrum of disease, which can be useful in the application of prophylactic vaccines against HPV and in the viral screening methods.

Effect of type-specific human papillomavirus incidence on screening performance and cost

BACKGROUND

Implementation of human papillomavirus (HPV) vaccination is expected to change the epidemiology of HPV infection.

METHODS

Using age-dependent (inhomogeneous) Markov chains, we tested the effect of type-specific (ie, HPV-16/HPV-18 and other high-risk HPV types) HPV incidence on 3 screening strategies in a cohort of 100,000 women, starting screening at the age of 25 years and continuing until the age of 34 years. All the strategies started with an HPV test; if the result was positive, the next step was triage with cytology (strategy 1), cytology and colposcopy together (strategy 2), or colposcopy only (strategy 3). Published background data were used for the models.

RESULTS

Strategy 2 had the highest sensitivity; the absolute number of missed cervical intraepithelial neoplasia (CIN)3+ cases was associated with HPV incidence in all the strategies, but their relative sensitivity remained unaffected. Strategy 2 was cheaper per diagnosed CIN3+ for very low HPV incidence rates, but this changed for higher incidence rates. For any given pair of HPV-16/HPV-18 and other high-risk-type incidence, the cost of the triage and the total cost of screening was highest in screening 2 and lowest in screening 1. For each screening strategy, the cost per diagnosed CIN3+ was mainly determined by the incidence of HPV-16/HPV-18, and the cost of the triage and the total screening cost by the incidence of other high-risk types.

CONCLUSIONS

Type-specific HPV incidence affects the absolute number of missed CIN3+ cases and the cost of screening in a mathematically describable way and can be used for prediction of changes in these outcomes with changing HPV epidemiology.

Prevalence and incidence of HPV genital infection in women

BACKGROUND

A prophylactic quadrivalent human papillomavirus (HPV) vaccine could benefit adult women if they are susceptible to incident genital HPV infections and are acquiring new infections with vaccine HPV types to which they were previously not exposed. This report presents baseline and prospective data from a randomized, double-blind, placebo-controlled trial of the safety, immunogenicity, and efficacy of the quadrivalent HPV (Type 6/11/16/18) vaccine in women ages 24 to 45.

METHODS

We present the results of an epidemiologic analysis of 3730 women enrolled in a quadrivalent HPV vaccine efficacy trial between June 18, 2004 and April 30, 2008. Subjects were enrolled from 7 countries (Colombia, France, Germany, Philippines, Spain, Thailand, and the United States) through community and academic health centers and primary health care providers.

RESULTS

Average baseline prevalence of anogenital infection and/or seropositivity was 32.8% for >or=1 vaccine HPV types and 0.3% for all vaccine HPV types. Incidence of anogential infection with any vaccine HPV type was approximately 10.5%. The rate of persistent infection was approximately 5% over a 30-month period among women in the placebo arm naïve to the relevant type at baseline. Predictors of incident infection included younger age, marital status other than first marriage, higher number of lifetime and recent sex partners, and Chlamydia/gonorrhea infection at baseline.

CONCLUSIONS

These findings indicate that women up to age 45 are susceptible to vaccine HPV types and some are acquiring anogenital infections with vaccine HPV types. Future study concerning incident and prevalent HPV infection among women up to age 45 is warranted (Trial NCT number NCT00090220).

Immunogenicity, reactogenicity, and safety of human papillomavirus 16/18 AS04-adjuvanted vaccine in Japanese women: interim analysis of a phase II, double-blind, randomized controlled trial at month 7

A phase II, double-blind, controlled randomized multicenter study with human papillomavirus (HPV) 16/18 AS04 (3-O-desacyl-4'-monophosphoryl lipid A and aluminum hydroxide)-adjuvanted vaccine is ongoing in Japanese women aged 20 to 25 years. An interim analysis was performed at month 7 (1 month after the third dose of vaccine) to determine reactogenicity, safety, and immunogenicity of the vaccine and to evaluate the baseline HPV-16/18 seropositivity and DNA status of women. In the HPV-16/18 group (according-to-protocol cohort for immunogenicity analysis), 100% seroconversion was observed against HPV-16 and HPV-18 at month 6 (5 months after the second dose) and at month 7. At month 7, anti-HPV-16 geometric mean titer (GMT) was 7441.0 enzyme-linked immunosorbent assay units/mL and anti-HPV-18 GMT was 3805.4 enzyme-linked immunosorbent assay units/mL, which is, respectively, 250- and 168-fold higher than GMTs observed after natural infection with HPV-16 or HPV-18. In the total vaccinated cohort, the seropositivity rates against HPV-16 and HPV-18 at study entry were 17.3% and 15.8%, respectively. At the same time point, HPV-16 and HPV-18 DNA was detected in 6.5% and 4.0% of the women, respectively. The immunogenicity of the HPV-16/18 vaccine and the HPV prevalence before vaccination in Japanese women are in line with what was observed in other populations. Injection site symptoms and some general symptoms were reported more frequently in the HPV-16/18 group than in the hepatitis A vaccine group but had no impact on compliance with completion of the vaccination course. Overall, the HPV-16/18 vaccine had a good safety profile, was well tolerated, and is highly immunogenic in the study population of Japanese women.

Time trends of human papillomavirus type distribution in Italian women with cervical intraepithelial neoplasia (CIN)

OBJECTIVE

It is assumed that the circulation of HPV types in a population is stable over time although there are limited historical data to support this view. The existence of possible cohort effects in the circulation of HPV types has major implications for vaccination strategies and risk assessment in HPV-infected women. We analysed archival biopsy samples of cervical intraepithelial neoplasia (CIN) to study the distribution of HPV types in Northern Italy over the years 1985-2007.

METHODS

DNA from formalin-fixed paraffin-embedded cervical biopsies from the years 1985-87 (67 samples) and 1995-97 (92 samples) was HPV-typed by the SPF-(10) Lipa assay. Cases were compared with 159 control biopsies from the years 2005-07 matched by patient age and CIN grade. Quantitative PCR was used to compare titres of HPV sequences in DNA extracted from biopsies of the three periods. Type-specific PCR was used to confirm HPV51 and 52 typing by SPF-(10) Lipa.

RESULTS

HPV51, 52, 53, 56, 58, and 66 were markedly under-represented or undetectable in samples from past periods whereas they represented 5.7-30.8% of present infections. Frequency of multiple HPV infections and high-risk infections (p=0.0001) also increased in recent years. The main changes occurred over the last decade. Infections by HPV16, 18, were three times more frequent 20 years ago than today (p=0.012). Loss of amplifiable HPV sequences over prolonged storage was not observed. Type-specific PCR confirmed all HPV51 and 52 infections.

CONCLUSIONS

Secular trends in the distribution of HPV types among women with CIN may occur in specific populations.

Natural history of human papillomavirus infections, cytologic and histologic abnormalities, and cancer

Over 100 human papillomavirus (HPV) types have been identified to date, of which over 40 infect the genital tract, primarily through sexual transmission. The many different genital HPV types appear to infect, resolve, or persist, and cause abnormal cytology and cervical intraepithelial neoplasia. Several cofactors have been associated with HPV persistence and lesion progression, including smoking, long-term oral contraceptive use, other sexually transmitted infections, host immunogenetics, and viral factors, such as HPV type and HPV variants. Given the discovery of HPV as the single primary cause of invasive cervical cancer, primary and secondary interventions have been realized, including HPV testing in cervical screening programs and prophylactic HPV vaccines. Because first generation HPV vaccines only target the two most common HPV types found in cervical cancer (HPV 16 and 18), cervical screening programs must continue, and the relative roles of HPV vaccination in young women and HPV testing in older women (alone or in conjunction with cytology) will be determined over the next decades.

Human papilloma virus (HPV) infection in children and adolescents

Human papilloma viruses (HPV) are common pathogens associated with a wide range of cutaneous and mucosal infections in childhood. Different HPV types can cause common warts, genital warts, low-grade as well as high-grade squamous intraepithelial lesions. Anogenital warts represent an issue with legal and clinical implications and evaluation of children for the possibility of sexual abuse should be considered in all cases. Recurrent respiratory papillomatosis has also been associated with HPV infection in a variety of studies. The recently introduced HPV vaccination is expected to prevent HPV-related cervical cancer in adulthood; however, HPV infection will continue to affect children.

Prevalence, acquisition, and clearance of cervical human papillomavirus infection among women with normal cytology: Hawaii Human Papillomavirus Cohort Study

Few natural history studies of cervical human papillomavirus (HPV) incidence and duration have been conducted among older women, especially from multiethnic populations. Viral and nonviral determinants of HPV acquisition and clearance were examined among 972 sexually active women, ages 18 to 85 years, recruited from clinics on Oahu, Hawaii, and followed for a mean duration of 15 months (range, 2-56 months). Interviews and cervical cell specimens for cytology and HPV DNA detection by PCR, using the PGMY09/PGMY11 primer system, were obtained at baseline and at 4-month intervals. The prevalence of cervical HPV infection was 25.6% at study entry. A total of 476 incident genotype-specific infections were observed during the follow-up period. The incidence of high-risk (HR) HPV types (9.26 per 1,000 woman-months) was similar to low-risk (LR) HPV types (8.24 per 1,000 woman-months). The most commonly acquired HR-HPV types were HPV-52, HPV-16, and HPV-31; and their incidence was increased significantly with a coexisting cervical HPV infection. Cervical HPV acquisition decreased with age, income, and long-term use of oral contraceptives and increased with number of sexual partners, use of hormonal creams, alcohol drinking, and condom use by a sexual partner. Cohort participants cleared 265 of the 476 incident infections during follow-up. LR-HPV infections cleared more rapidly than did HR-HPV infections (median, 180 days versus 224 days). Clearance times were enhanced among older women and women with multiple infections. Our data suggest several viral and nonviral determinants of cervical HPV acquisition and clearance that might be used in cervical cancer prevention programs.

Human papillomavirus prevalence in women attending routine cervical screening in South Wales, UK: a cross-sectional study

In this cross-sectional population-based study we determine human papillomavirus (HPV) prevalence in South Wales to provide comprehensive baseline data for future assessment of the impact of prophylactic HPV vaccination and to help inform future screening strategies. Liquid-based cytology samples from women attending routine cervical screening were collected (n=10 000: mean age 38 years, 93% cytology negative, and 64.8% from the 50% least deprived LSOA according to social deprivation score (SDS)). High-Risk (HR) and Low-Risk HPV screening was performed using HPV PCR-EIA with genotyping of HR positives and data correlated with age, SDS and cytology. Overall HPV prevalence was 13.5% (9.3% age standardised) and the most frequent HR types were HPV 16, 31, 18 and 58. In HR HPV-positive cases 42.4% had a single HR type and they were predominant in women with severe cytological abnormalities. Here, 66% of all HR HPV cases were in women aged 30 years of age or less and SDS had no significant effect on HPV status. HPV prevalence increased significantly with degree of dyskarosis from 7% in cytology negative samples to 80% in samples with severe cytological abnormalities (P-value <0.0001). Overall, 46% of HR HPV cases were positive for the two HR types targeted by the prophylactic vaccines (HPV 16 and HPV 18). The data presented represents the largest type-specific investigation of HPV prevalence in an unselected UK population.

Descriptive evidence that risk profiles for cervical intraepithelial neoplasia 1, 2, and 3 are unique

OBJECTIVE

This study aimed to estimate if risk factor profiles for histologically confirmed cervical intraepithelial neoplasia (CIN) 2 lesions differ from those for CIN 1 or 3.

METHODS

A total of 2,055 women positive for high-risk human papillomavirus, with a minimum of five cervical biopsies, were enrolled in the Shanxi Province Cervical Cancer Screening Study II. We evaluated risk factor profiles for CIN 2 in comparison with CIN 1 and 3. Polytomous logistic regression was used to generate odds ratios and corresponding 95% confidence intervals and to test for differences in odds ratios across histologic grades.

RESULTS

The risk for CIN 3 associated with three or more pregnancies and sexual intercourse within 4 months of childbirth was higher than that for CIN 2 (P(difference) = 0.02 and 0.0007, respectively). Significant differences in the associations of age groups with CIN 1 and 2 were observed, such that there were positive associations with CIN 2 but none for CIN 1. There was no difference in the association of number of sexual partners or reported number of abortions between CIN 1 and 2 or between CIN 3 and 2.

CONCLUSIONS

In our study, the patterns of risk factor profiles for CIN 1, 2, and 3 were unique. Conventional grouping of CIN 2 with 3 for analysis of risk factors may need revisiting.

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.

Specificity of L1 peptides versus virus-like particles for detection of human papillomavirus-positive cervical lesions in females attending Engativa Hospital, Bogota, Colombia

A serological test for the detection of human papillomavirus (HPV) infection in females at risk of developing cervical cancer could be based on conserved L1 peptides with low levels of antigenicity specifically recognized by antibodies from patients with cervical lesions infected with high-risk HPV (HR-HPV) types. The aim was to assess the ability of L1 peptides 18283, 18294, and 18301 compared with the ability of virus-like particles (VLPs) to identify these infections in females. A total of 391 HPV-infected female volunteers were interviewed, and peripheral blood and cervical cells were obtained for detection of anti-HPV antibodies and HPV DNA; all of the patients had a Pap smear test; 287 patients were referred for colposcopy or biopsy, according to gynecological criteria. The level of agreement, as determined by the use of the Lin coefficient (rho value), showed that 75 to 83% of females with HR-HPV DNA-positive cervical lesions had antibodies that recognized VLPs and peptide 18283, 18294, or 18301, while 15 to 23% of the HPV DNA-negative females with a normal cytology had antibodies that recognized these three peptides and 45% had antibodies that recognized VLPs. The rate of agreement between peptides and VLPs for antibody detection was higher for patients with HPV DNA-positive cervical lesions. Peptides 18283, 18294, and 18301 showed similar sensitivities for the detection of HR-HPV DNA-positive cervical lesions and were more specific than VLPs. Peptide 18301 might be detecting protective antibodies in HPV DNA-negative females with atypical squamous cells of undetermined significance. These peptides could be useful for the design of a serology test for the detection of HR-HPV infection in females with cervical lesions and at risk of cervical cancer.

Persistent human papillomavirus infection and cervical neoplasia: a systematic review and meta-analysis

Detection of persistent cervical carcinogenic human papillomavirus (HPV) DNA is used as a marker for cervical cancer risk in clinical trials. The authors performed a systematic review and meta-analysis of the association between persistent HPV DNA and high-grade cervical intraepithelial neoplasia (CIN2-3), high-grade squamous intraepithelial lesions (HSIL), and invasive cervical cancer (together designated CIN2-3/HSIL+) to evaluate the robustness of HPV persistence for clinical use. MEDLINE and Current Contents were searched through January 30, 2006. Relative risks (RRs) were stratified by HPV comparison group. Of 2,035 abstracts, 41 studies were eligible for inclusion in the meta-analysis. Over 22,500 women were included in calculation of RRs for persistent HPV DNA detection and cervical neoplasia. RRs ranged from 1.3 (95% confidence interval: 1.1, 1.5) to 813.0 (95% confidence interval: 168.2, 3,229.2) for CIN2-3/HSIL+ versus <CIN2-3/HSIL+; 92% of RRs were above 3.0. Longer durations of infection (>12 months), wider testing intervals, CIN2-3/HSIL+, and use of an HPV-negative reference group were consistently associated with higher RRs. Thus, HPV persistence was consistently and strongly associated with CIN2-3/HSIL+, despite wide variation in definitions and study methods. The magnitude of association varied by duration of persistence and testing interval. Precise definition and standardization of HPV testing, sampling procedure, and test interval are needed for reliable clinical testing. These findings validate HPV persistence as a clinical marker and endpoint.

Prevalence of type-specific HPV infection by age and grade of cervical cytology: data from the ARTISTIC trial

Human papillomavirus (HPV) infection causes cervical cancer and premalignant dysplasia. Type-specific HPV prevalence data provide a basis for assessing the impact of HPV vaccination programmes on cervical cytology. We report high-risk HPV (HR-HPV) type-specific prevalence data in relation to cervical cytology for 24,510 women (age range: 20-64; mean age 40.2 years) recruited into the ARTISTIC trial, which is being conducted within the routine NHS Cervical Screening Programme in Greater Manchester. The most common HR-HPV types were HPV16, 18, 31, 51 and 52, which accounted for 60% of all HR-HPV types detected. There was a marked decline in the prevalence of HR-HPV infection with age, but the proportion due to each HPV type did not vary greatly with age. Multiple infections were common below the age of 30 years but less so between age 30 and 64 years. Catch-up vaccination of this sexually active cohort would be expected to reduce the number of women with moderate or worse cytology by 45%, but the number with borderline or mild cytology would fall by only 7%, giving an overall reduction of 12% in the number of women with abnormal cytology and 27% in the number with any HR-HPV infection. In the absence of broader cross-protection, the large majority of low-grade and many high-grade abnormalities may still occur in sexually active vaccinated women.

Long-term outcomes of high-risk human papillomavirus infection support a long interval of cervical cancer screening

Knowing that infection of high-risk human papillomavirus (HPV) causes virtually all cervical cancer (CC), the long-term outcomes of HPV infection, especially the absolute risk and time lapse of developing CC, are beyond the scope of ordinary follow-up study owing to ethical concerns. The present study followed the natural history and long-term outcomes of HPV infection in a cohort of women by national health insurance care and data linkage without additional disturbance. The status of cervical HPV infection was determined in 1708 healthy women, aged 20–90 (median 43), enrolled from 10 hospitals in seven cities around the island country of Taiwan. Records of consecutive Pap smear results and cancer reports of 108 cytology-negative, HPV-positive and 1202 cytology- and HPV-negative women with no prior record of CC or abnormal cervical cytology were retrospectively analysed for a duration of up to 75 months (median 61 months). The cumulative incidences of high-grade squamous intraepithelial lesion (HSIL) and in situ/invasive cancer in HPV-positive women were 5.6 and 3.7%, respectively, and those in HPV-negative women were 0.3 and 0%. After adjusting for other risk factors, HPV-positive subjects had 24.9 (95% CI: 7.0–108.3; P<0.0001) folds of risk of developing HSIL or above cervical neoplasia as compared to HPV-negative subjects, whereas risk for low-grade intraepithelial lesion and atypical squamous cytology was not increased. The study showed that women with a prevalent infection of high-risk HPV had a 4% cumulative risk for CC in 6 years, whereas those tested negative had little risk. The result supports an HPV test-orientated CC screening programme with intervals of at least 5 years.

A cost-effectiveness analysis of adding a human papillomavirus vaccine to the Australian National Cervical Cancer Screening Program

BACKGROUND

The cost-effectiveness of adding a human papillomavirus (HPV) vaccine to the Australian National Cervical Screening Program compared to screening alone was examined.

METHODS

A Markov model of the natural history of HPV infection that incorporates screening and vaccination was developed. A vaccine that prevents 100% of HPV 16/18-associated disease, with a lifetime duration of efficacy and 80% coverage offered through a school program to girls aged 12 years, in conjunction with current screening was compared with screening alone using cost (in Australian dollars) per life-year (LY) saved and quality-adjusted life-year (QALY) saved. Sensitivity analyses included determining the cost-effectiveness of offering a catch-up vaccination program to 14-26-year-olds and accounting for the benefits of herd immunity.

RESULTS

Vaccination with screening compared with screening alone was associated with an incremental cost-effectiveness ratio (ICER) of $51 103 per LY and $18 735 per QALY, assuming a cost per vaccine dose of $115. Results were sensitive to assumptions about the duration of vaccine efficacy, including the need for a booster ($68 158 per LY and $24 988 per QALY) to produce lifetime immunity. Accounting for herd immunity resulted in a more attractive ICER ($36 343 per LY and $13 316 per QALY) for girls only. The cost per LY of vaccinating boys and girls was $92 052 and the cost per QALY was $33 644. The cost per LY of implementing a catch-up vaccination program ranged from $45 652 ($16 727 per QALY) for extending vaccination to 14-year-olds to $78 702 ($34 536 per QALY) for 26-year-olds.

CONCLUSIONS

These results suggest that adding an HPV vaccine to Australia's current screening regimen is a potentially cost-effective way to reduce cervical cancer and the clinical interventions that are currently associated with its prevention via screening alone.

Modelling the population-level impact of vaccination on the transmission of human papillomavirus type 16 in Australia

BACKGROUND

Vaccines are now available to prevent the development of cervical cancer from genital human papillomavirus (HPV) infection. The decision to vaccinate depends on a vaccine's cost-effectiveness. A rigorous cost-effectiveness model for vaccinated individuals is presented in a companion paper; this paper investigates the additional benefits the community might receive from herd immunity.

METHODS

A mathematical model was developed to estimate the impact of a prophylactic vaccine on transmission of HPV type 16 in Australia. The model was used to estimate the expected reduction in HPV incidence and prevalence as a result of vaccination, the time required to achieve these reductions, and the coverage required for elimination. The modelled population was stratified according to age, gender, level of sexual activity and HPV infection status using a differential equation formulation. Clinical trials show that the vaccine is highly effective at preventing persistent infection and pre-cancerous lesions. These trials do not, however, provide conclusive evidence that infection is prevented altogether. The possible modes of vaccine action were investigated to see how vaccination might change the conclusions.

RESULTS

The model predicts that vaccination of 80% of 12-year-old girls will eventually reduce HPV 16 prevalence by 60-100% in vaccinated and 7-31% in unvaccinated females. If 80% of boys are also vaccinated, reductions will be 74-100% in vaccinated and 86-96% in unvaccinated females. A campaign covering only 12-year-old girls would require 5-7 years to achieve 50% of the eventual reduction. With a catch-up campaign covering 13-26-year-olds, this delay would be reduced to only 2 years. Unrealistically high coverage in both sexes would be required to eliminate HPV 16 from the population. Under pessimistic assumptions about the duration of vaccine-conferred immunity, HPV 16 incidence is predicted to rise in some older age groups.

CONCLUSIONS

Mass vaccination with a highly effective vaccine against HPV 16 has the potential to substantially reduce the incidence and prevalence of infection. Catch-up vaccination offers the potential to substantially reduce the delay before the benefits of vaccination are observed. A booster vaccination might be required to prevent an increase in incidence of infection in women over 25 years of age.

HPV vaccines: are they the answer?

BACKGROUND

The burden of human papillomavirus (HPV)-associated ano-genital disease is significant but the ability to generate HPV virus-like particles by the synthesis and self-assembly in vitro of the major virus coat protein L1 has transformed our prospects for preventing benign and malignant ano-genital disease caused by the common genital HPV types.

SOURCES OF DATA

Peer reviewed journals.

AREAS OF AGREEMENT

Two HPV L1 vaccines have been developed, a quadrivalent HPV 6/11/16/18, and a bivalent HPV 16/18 product. Both vaccines are very immunogenic and well tolerated. They have been shown in the various randomized Control trials to be very effective at preventing infection and premalignant disease related to the vaccine HPV genotypes in women who were DNA negative and sero negative for the vaccine HPV types at base line. The protection against disease generated by the vaccines persists for at least 5 years. HPV vaccines containing HPV 6/11 will reduce the incidence of genital warts by 80-90% in the medium term. The vaccines will reduce but not eliminate the risk of cervical cancer since at the present they only target two of the oncogenic genital types. Cervical cancer screening programmes will remain as important secondary interventions for cervical cancer even in vaccinated populations.

AREAS OF CONTROVERSY

The duration of protection remains unknown but there is evidence of good immune memory, it is possible that protection will be long lasting. The primary target group for cost effective immunization with HPV vaccines are peri-pubertal females. There may be benefit in vaccinating other groups (men, sexually active women of all ages) but the cost effectiveness of these interventions will need to be evaluated. In societies in which organized screening programmes are not available, HPV vaccines are probably the most realistic intervention against HPV-associated disease.

AREAS TIMELY FOR DEVELOPING RESEARCH

Second generation vaccines that offer protection against additional types, are thermostable and delivered by non-injection methods are an important area of investigation.

Correlates of parents' reports of acceptability of human papilloma virus vaccination for their school-aged children

Background: Routine human papilloma virus (HPV) vaccination for 12–13-year-old girls will be introduced in the UK from September 2008. The aim of the present study was to identify correlates of parents’ anticipated uptake of HPV vaccination for their sons and daughters. Methods: Self-administered questionnaires were completed by 353 parents of school-aged children living in Brighton and Hove (England). The main outcome measure was anticipated acceptance of HPV vaccination for children. Putative predictors of acceptance of HPV vaccination included general attitudes toward vaccination, beliefs about the impact on adolescent sexual behaviour of vaccines against sexually transmissible infections, and knowledge of HPV and cervical cancer. Results: Multivariate regression revealed that greater perceived benefits of HPV vaccination, greater general belief in the protection offered by vaccination, and greater support for adolescent sexual health services explained substantial proportions of the variance in HPV vaccine acceptability for both sons and daughters. For both sons and daughters, the most important correlate of vaccine acceptability was general belief in the protection offered by vaccination: this variable explained 40–50% of variance. Acceptability of vaccination appeared to improve following the provision of brief information about the links between HPV and cervical cancer and the proposed introduction of HPV vaccination. Conclusions: Uptake of HPV vaccination may be maximised by: improving attitudes toward the safety and efficacy of childhood vaccinations; countering concerns that provision of sexual health services for young people will encourage promiscuous or unsafe sexual behaviour; and improving knowledge about the role of HPV in cervical cancer aetiology.

2006 consensus guidelines for the management of women with abnormal cervical screening tests

OBJECTIVE

To provide revised evidence-based consensus guidelines for managing women with abnormal cervical cancer screening test results.

PARTICIPANTS

A group of 146 experts, including representatives from 29 professional organizations, federal agencies, and national and international health organizations, met in Bethesda, MD, September 18-19, 2006, to develop the guidelines. MAJOR CHANGES IN GUIDELINES: The core recommendations for managing women with atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesions were changed minimally. Postcolposcopy management for women with these cytological abnormalities is now identical. Management recommendations for these conditions did change for "special populations," such as adolescents for whom a more conservative approach incorporating cytological follow-up for 2 years was approved. Core recommendations for managing women with high-grade squamous intraepithelial lesions and atypical glandular cells also underwent only minor modifications. More emphasis is placed on immediate "screen-and-treat" approaches when managing women with high-grade squamous intraepithelial lesion. Testing for high-risk human papillomavirus DNA is incorporated into the management of women with atypical glandular cells after their initial evaluation with colposcopy and endometrial sampling. The 2004 Interim Guidance for the use of human papillomavirus DNA testing as an adjunct to cervical cytology for screening in women 30 years and older was formally adopted with only very minor modifications.

CONCLUSIONS

The 2006 Consensus Guidelines reflect recent data from large clinical trials and advances in technology and are designed to assist clinicians of all subspecialties.

Potential effects of decreased cervical cancer screening participation after HPV vaccination: an example from the U.S

A concern with widespread implementation of HPV vaccination programs is that women may mistakenly decide that they do not need to be screened any longer, and thus be less likely to participate in cervical cancer screening, because they view themselves to be at low-risk of developing cervical cancer. We hypothesized that non-participation in screening among vaccinated young women in the 5 years following vaccination may result in missed CIN 2-3 cases that could progress to cancer. For instance, if 50% fewer women 26-30 years old, who were vaccinated, participate in screening in the United States over a 5 year time horizon, there would be approximately 4 women (per 1000) with missed CIN 2-3. On the other hand, non-participation will reduce the number of false-positive screening test results, as non-participation would avoid approximately 27 false-positive test results, with a decrease in follow-up procedures and costs. These results highlight the importance of educating women to ensure continued screening, as well as the need to consider new approaches to screening in the era of vaccination.

2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests

A group of 146 experts representing 29 organizations and professional societies met September 18-19, 2006, in Bethesda, MD, to develop revised evidence-based, consensus guidelines for managing women with abnormal cervical cancer screening tests. Recommendations for managing atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion (LSIL) are essentially unchanged. Changes were made for managing these conditions in adolescents for whom cytological follow-up for 2 years was approved. Recommendations for managing high-grade squamous intraepithelial lesion (HSIL) and atypical glandular cells (AGC) also underwent only minor modifications. More emphasis is placed on immediate screen-and-treat approaches for HSIL. Human papillomavirus (HPV) testing is incorporated into the management of AGC after their initial evaluation with colposcopy and endometrial sampling. The 2004 Interim Guidance for HPV testing as an adjunct to cervical cytology for screening in women 30 years of age and older was formally adopted with only very minor modifications.

Human papillomavirus (HPV) genotype distribution in invasive cervical cancers in France: EDITH study

Invasive cervical cancer (ICC) remains a significant cause of morbidity and mortality in France. Since human papillomavirus (HPV) is the necessary cause of ICC, the aim of this study was to assess the type-specific prevalence of HPV in ICC in France in order to locally evaluate the potential benefit of an HPV 16/18 L1 virus-like particles (VLP) vaccination. A total of 516 histological specimens collected in 15 centers were analyzed. Among them, 86% had a diagnosis of squamous cell carcinoma (SCC) whereas 14% were adenocarcinomas (ADC). HPV genotyping was performed using the INNO-LiPA assay allowing the specific detection of 24 HPV genotypes both high risk (HR) and low risk (LR). The overall HPV prevalence in ICC was 97%. The most prevalent genotypes were HPV 16 (73%) and HPV 18 (19%) followed by HPV 31 (7%), 33, 68, 45, 52 and 58 (4.1-2.3%). HPV 16 and/or 18 were associated with 82% of ICC, 10% being HPV 16 and 18 coinfections. While HPV 16 was the most prevalent type in both SCC (74%) and ADC (64%), HPV 18 was by far more prevalent in ADC (37%) compared to SCC (16%; p < 0.001). Multiple infections with at least two different HR HPV genotypes were observed in 22% of ICC. Given the high HPV 16/18 prevalence and taking into account possible production of crossneutralizing antibodies against other HPV types, HPV 16/18 L1 VLP vaccination would be expected to significantly reduce the burden of ICC in France.

Baseline human papillomavirus status of women with abnormal smears in cervical screening: a 5-year follow-up study in the Netherlands

OBJECTIVE

To determine in a screening population the human papillomavirus (HPV) status in those with cytological abnormalities and to evaluate the presence of high-risk (HR) HPV with a minimum of 5-year follow up.

DESIGN

Retrospective examination of HPV status on prospectively collected and cytologically screened cervical smears.

SETTING

Canisius-Wilhelmina Hospital in Nijmegen, The Netherlands.

POPULATION

Three hundred and fifty-seven women aged 30-60 years, from the population screened.

METHODS

Three hundred and fifty-seven women with borderline or higher cytological abnormalities were retrospectively examined for HPV with DNA microarray typing. Follow up was through the nationwide Dutch Pathology database (PALGA).

MAIN OUTCOME MEASURES

For the cytological abnormalities, the CISOE-A classification was used. HPV was scored as negative or positive. In case of positive HPV polymerase chain reaction, the HPV genotype was determined. The occurrence of cervical intraepithelial neoplasia lesions of grade 3 or higher was considered as endpoint for follow up.

RESULTS

The majority of the women with borderline cytology in this study were HPV negative (87%). Among the HPV-positive women in borderline cytology group, 74% had HR-HPV or probable high-risk types. The overall percentage of HR-HPV types increased with progressive cytological abnormalities. The cytological classifications of borderline dyskaryosis and moderate dyskaryosis contain all types of HPVs, e.g. low risk, HR and unknown risk. The samples with severe dyskaryosis or higher contain only HR types. The negative predictive value for HR-HPV typing in the group with borderline cytological abnormalities is more than 99%.

CONCLUSIONS

In cervical screening with an interval of 5 years, HPV can be reliably used as triage point in cases of borderline cytological abnormalities.

Papanicolaou smear history in women with low-grade cytology before cervical cancer diagnosis

BACKGROUND

The purpose of the current study was to examine the screening histories of women diagnosed with invasive cervical cancer (ICC) in 2000 who had previous Papanicolaou (Pap) smears deemed to be unsatisfactory or with low-grade findings that did not lead to biopsy.

METHODS

A total of 252 Pap smears from 47 women taken between 1992 and 2000 were included in the study; 247 smears were reexamined at the laboratory of origin before the study and all 252 were then reexamined independently by 2 experienced cytotechnicians and 2 cytopathologists.

RESULTS

Of the 47 cases of ICC, 35 were squamous cell carcinoma, 10 were adenocarcinoma, and 2 were other types. On reexamination at the laboratory of origin, 24 cases were upgraded and in the study group 27 cases were upgraded to diagnoses requiring biopsy. On reexamination at the laboratory of origin, it was found that the first high-grade squamous intraepithelial lesion (HSIL) could have been diagnosed on average 4.2 years earlier than it was originally (95% confidence interval [95% CI], 3.3-5.1 years). On reexamination by the study group the first diagnosis of HSIL was made in smears dating from 5.4 years before the diagnosis of ICC (95% CI, 4.5-6.2 years).

CONCLUSIONS

The study confirms that unsatisfactory and low-grade Pap smears imply a risk of developing high-grade lesions at a later date and shows that in a screening program a subgroup of smears may be diagnosed as unsatisfactory or low grade despite the presence of high-grade findings that are detectable on reexamination.

HPV type-specific risks of high-grade CIN during 4 years of follow-up: a population-based prospective study

We followed a population-based cohort of 5696 women, 32–38 years of age, by registry linkage with cytology and pathology registries during a mean follow-up time of 4.1 years to assess the importance for CIN2+ development of type-specific HPV DNA positivity at baseline. HPV 16, 31 and 33 conveyed the highest risks and were responsible for 33.1, 18.3 and 7.7% of CIN2+ cases, respectively. Women infected with HPV 18, 35, 39, 45, 51, 52, 56, 58, 59 and 66 had significantly lower risks of CIN2+ than women infected with HPV 16. After adjustment for infection with other HPV types, HPV types 35, 45, 59 and 66 had no detectable association with CIN2+. In summary, the different HPV types found in cervical cancer show distinctly different CIN2+ risks, with high risks being restricted to HPV 16 and its close relatives HPV 31 and HPV 33.

Quadrivalent vaccine against human papillomavirus to prevent high-grade cervical lesions

BACKGROUND

Human papillomavirus types 16 (HPV-16) and 18 (HPV-18) cause approximately 70% of cervical cancers worldwide. A phase 3 trial was conducted to evaluate a quadrivalent vaccine against HPV types 6, 11, 16, and 18 (HPV-6/11/16/18) for the prevention of high-grade cervical lesions associated with HPV-16 and HPV-18.

METHODS

In this randomized, double-blind trial, we assigned 12,167 women between the ages of 15 and 26 years to receive three doses of either HPV-6/11/16/18 vaccine or placebo, administered at day 1, month 2, and month 6. The primary analysis was performed for a per-protocol susceptible population that included 5305 women in the vaccine group and 5260 in the placebo group who had no virologic evidence of infection with HPV-16 or HPV-18 through 1 month after the third dose (month 7). The primary composite end point was cervical intraepithelial neoplasia grade 2 or 3, adenocarcinoma in situ, or cervical cancer related to HPV-16 or HPV-18.

RESULTS

Subjects were followed for an average of 3 years after receiving the first dose of vaccine or placebo. Vaccine efficacy for the prevention of the primary composite end point was 98% (95.89% confidence interval [CI], 86 to 100) in the per-protocol susceptible population and 44% (95% CI, 26 to 58) in an intention-to-treat population of all women who had undergone randomization (those with or without previous infection). The estimated vaccine efficacy against all high-grade cervical lesions, regardless of causal HPV type, in this intention-to-treat population was 17% (95% CI, 1 to 31).

CONCLUSIONS

In young women who had not been previously infected with HPV-16 or HPV-18, those in the vaccine group had a significantly lower occurrence of high-grade cervical intraepithelial neoplasia related to HPV-16 or HPV-18 than did those in the placebo group. (ClinicalTrials.gov number, NCT00092534 [ClinicalTrials.gov].).

[Contribution of HPV sequences detection in cervical carcinoma screening]

At the present time, Human Papillomaviruses (HPV) is a leading cause of squamous intraepithelial lesions (SIL) and invasive carcinoma of the cervix. The aim of this article was to review the main taxonomic and epidemiologic data on HPV infection and to assess the potential clinical implications of the different HPV tests in staging women with borderline cytologies (ASC-US; ASC-H; LSIL); for follow-up after treatment of high-grade cervical intraepithelial neoplasia (CIN), for primary screening as the sole screening modality, or in association with cytology.

Prévention des infections à papillomavirus et du zona : nouveaux vaccins

Two new vaccines have been recently licensed : a quadrivalent vaccine against Human papillomavirus infections (HPV) 6, 11, 16 and 18, recommended to children from 9 years old and to young adults under the age of 26 years, and a vaccine against herpes zoster for adults from 60 years old onwards. A bivalent vaccine against HPV 16 and 18 will be shortly available. HPV vaccines are composed of the L1 structural proteins of 2 or 4 HPV genotypes, produced by genetic engineering and self-assembled. These inert vaccines are devoid of genetic materials and mimic the viral particle (virus-like particle, VLP). They allow, as suggested by the 4.5 to 5 years follow-up, to prevent HPV infections and the onset of pre-cancerous lesions associated with genotypes contained within the vaccine. They represent a major overhang in the vaccinology field, and, as anti-hepatitis B vaccine, will probably be effective in cancer prevention. Their use must be associated with the continued detection of cervix cancer by smears and also with the prevention of other sexually transmitted diseases. The herpes zoster vaccine is a living attenuated vaccine produced from the OKA/Merck strain already used in the vaccine against varicella. Its safety is good among persons 50 years old and over and its efficiency on lowering herpes zoster incidence, on the burden of illness and on post-herpetic neuralgia has been demonstrated in persons over 60 years old.

High-risk HPV type-specific clearance rates in cervical screening

We assessed clearance rates of 14 high-risk human papillomavirus (hrHPV) types in hrHPV-positive women with normal cytology and borderline/mild dyskaryosis (BMD) in a population-based cervical screening cohort of 44,102 women. The 6-month hrHPV type-specific clearance rates, that is, clearance of the same type as detected at baseline, in women with normal and BMD smears were 43% (95% confidence interval (CI) 39-47) and 29% (95% CI 24-34), respectively. Corresponding 18-month clearance rates were markedly higher, namely 65% (95% CI 60-69) and 41% (95% CI 36-47), respectively. The lowest clearance rates in women with normal cytology were observed for HPV16, HPV18, HPV31, and HPV33. Significantly reduced 18-month clearance rates at a significance level of 1% were observed for HPV16 (49%, 95% CI 41-59) and HPV31 (50%, 95% CI 39-63) in women with normal cytology, and for HPV16 (19%, 95% CI 12-29) in women with BMD. Among women who did not clear hrHPV, women with HPV16 persistence displayed an increased detection rate of >or=CIN3 (normal P<0.0001; BMD, P=0.005). The type-specific differences in clearance rates indicate the potential value of hrHPV genotyping in screening programs. Our data support close surveillance (i.e. referral directly, or within 6 months) of women with HPV16 and are inconclusive for surveillance of women with HPV18, HPV31, and HPV33. For the other hrHPV-positive women, it seems advisable to adopt a conservative management with a long waiting period, as hrHPV clearance is markedly higher after 18 months than after 6 months and the risk for >or=CIN3 is low.

Estimating the long-term impact of a prophylactic human papillomavirus 16/18 vaccine on the burden of cervical cancer in the UK

To predict the public health impact on cervical disease by introducing human papillomavirus (HPV) vaccination in the United Kingdom, we developed a mathematical model that can be used to reflect the impact of vaccination in different countries with existing screening programmes. Its use is discussed in the context of the United Kingdom. The model was calibrated with published data. The impact of vaccination on cervical cancer and deaths, precancerous lesions and screening outcomes were estimated for a vaccinated cohort of 12-year-old girls, among which it is estimated that there would be a reduction of 66% in the prevalence of high-grade precancerous lesions and a 76% reduction in cervical cancer deaths. Estimates for various other measures of the population effects of vaccination are also presented. We concluded that it is feasible to forecast the potential effects of HPV vaccination in the context of an existing national screening programme. Results suggest a sizable reduction in the incidence of cervical cancer and related deaths. Areas for future research include investigation of the beneficial effects of HPV vaccination on infection transmission and epidemic dynamics, as well as HPV-related neoplasms in other sites.