Planning for resilience in screening operations using discrete event simulation modeling: example of HPV testing in Peru

Background

The World Health Organization (WHO) has called for the elimination of cervical cancer. Unfortunately, the implementation of cost-effective prevention and control strategies has faced significant barriers, such as insufficient guidance on best practices for resource and operations planning. Therefore, we demonstrate the value of discrete event simulation (DES) in implementation science research and practice, particularly to support the programmatic and operational planning for sustainable and resilient delivery of healthcare interventions. Our specific example shows how DES models can inform planning for scale-up and resilient operations of a new HPV-based screen and treat program in Iquitos, an Amazonian city of Peru.

Methods

Using data from a time and motion study and cervical cancer screening registry from Iquitos, Peru, we developed a DES model to conduct virtual experimentation with “what-if” scenarios that compare different workflow and processing strategies under resource constraints and disruptions to the screening system.

Results

Our simulations show how much the screening system’s capacity can be increased at current resource levels, how much variability in service times can be tolerated, and the extent of resilience to disruptions such as curtailed resources. The simulations also identify the resources that would be required to scale up for larger target populations or increased resilience to disruptions, illustrating the key tradeoff between resilience and efficiency. Thus, our results demonstrate how DES models can inform specific resourcing decisions but can also highlight important tradeoffs and suggest general “rules” for resource and operational planning.

Conclusions

Multilevel planning and implementation challenges are not unique to sustainable adoption of cervical cancer screening programs but represent common barriers to the successful scale-up of many preventative health interventions worldwide. DES represents a broadly applicable tool to address complex implementation challenges identified at the national, regional, and local levels across settings and health interventions—how to make effective and efficient operational and resourcing decisions to support program adaptation to local constraints and demands so that they are resilient to changing demands and more likely to be maintained with fidelity over time.

The Implementation of a Primary HPV Self-Testing Cervical Screening Program in Malaysia through Program ROSE-Lessons Learnt and Moving Forward

Program ROSE (removing obstacles to cervical screening) is a primary HPV-based cervical screening program that incorporates self-sampling and digital technology, ensuring that women are linked to care. It was developed based on the principles of design thinking in the context of Malaysia. The program illustrates the importance of collaborative partnerships and addressing the multi-faceted barriers from policy changes, and infrastructure readiness to the implementation of a radically new cervical screening program in communities. The paradigm shift in cervical cancer requires a monumental and concerted effort in educating both the healthcare providers and the general public. In this short review, we highlight how Pilot Project ROSE incorporated evidence-based tools that rapidly scaled up to Program ROSE. These ideas and solutions can be adapted and adopted by other countries. Notwithstanding the impact of COVID-19, it is incumbent on countries to pave the road towards the elimination of cervical cancer with pre-existing footpaths.

Implementation research to accelerate scale-up of national screen and treat strategies towards the elimination of cervical cancer

BACKGROUND

Cervical cancer is a significant public health problem, with 570,000 new cases and 300,000 deaths of women per year globally, mostly in low- and middle-income countries. In 2018 the WHO Director General made a call to action for the elimination of cervical cancer as a public health problem.

MAIN BODY

New thinking on programmatic approaches to introduce emerging technologies and screening and treatment interventions of cervical precancer at scale is needed to achieve elimination goals. Implementation research (IR) is an important yet underused tool for facilitating scale-up of evidence-based screening and treatment interventions, as most research has focused on developing and evaluating new interventions. It is time for countries to define their specific IR needs to understand acceptability, feasibility, and cost-effectiveness of interventions as to design and ensure effective implementation, scale-up, and sustainability of evidence-based screening and treatment interventions. WHO convened an expert advisory group to identify priority IR questions for HPV-based screening and treatment interventions in population-based programmes. Several international organizations are supporting large scale introduction of screen-and-treat approaches in many countries, providing ideal platforms to evaluate different approaches and strategies in diverse national contexts.

CONCLUSION

For reducing cervical cancer incidence and mortality, the readiness of health systems, the reach and effectiveness of new technologies and algorithms for increasing screening and treatment coverage, and the factors that support sustainability of these programmes need to be better understood. Answering these key IR questions could provide actionable guidance for countries seeking to implement the WHO Global Strategy towards cervical cancer elimination.

Supporting scale-up of COVID-19 RT-PCR testing processes with discrete event simulation

Testing is critical to mitigating the COVID-19 pandemic, but testing capacity has fallen short of the need in the United States and elsewhere, and long wait times have impeded rapid isolation of cases. Operational challenges such as supply problems and personnel shortages have led to these bottlenecks and inhibited the scale-up of testing to needed levels. This paper uses operational simulations to facilitate rapid scale-up of testing capacity during this public health emergency. Specifically, discrete event simulation models were developed to represent the RT-PCR testing process in a large University of Maryland testing center, which retrofitted high-throughput molecular testing capacity to meet pandemic demands in a partnership with the State of Maryland. The simulation models support analyses that identify process steps which create bottlenecks, and evaluate “what-if” scenarios for process changes that could expand testing capacity. This enables virtual experimentation to understand the trade-offs associated with different interventions that increase testing capacity, allowing the identification of solutions that have high leverage at a feasible and acceptable cost. For example, using a virucidal collection medium which enables safe discarding of swabs at the point of collection removed a time-consuming “deswabbing” step (a primary bottleneck in this laboratory) and nearly doubled the testing capacity. The models are also used to estimate the impact of demand variability on laboratory performance and the minimum equipment and personnel required to meet various target capacities, assisting in scale-up for any laboratories following the same process steps. In sum, the results demonstrate that by using simulation modeling of the operations of SARS-CoV-2 RT-PCR testing, preparedness planners are able to identify high-leverage process changes to increase testing capacity.

Accelerating action on cervical screening in lower- and middle-income countries (LMICs) post COVID-19 era

Cervical cancer remains the fourth most common cancer in women, with 85% of deaths occurring in LMICs. Despite the existence of effective vaccine and screening tools, efforts to reduce the burden of cervical cancer must be considered in the context of the social structures within the health systems of LMICs. Compounding this existing challenge is the global COVID-19 pandemic, declared in March 2020. While it is too soon to tell how health systems priorities will change as a result of COVID-19 and its impact on the cervical cancer elimination agenda, there are opportunities to strengthen cervical screening by leveraging on several trends. Many LMICs maximized the strengths of their long established community-based primary care and public health systems with expansion of surveillance systems which incorporated mobile technologies. LMICs can harness the momentum of the measures taken against COVID-19 to consolidate the efforts against cervical cancer. Self-sampling, molecular human papillomavirus (HPV) testing and digital health will shift health systems towards stronger public health and primary care networks and away from expensive hospital-based care investments. While COVID-19 will change health systems priorities in LMICs in ways that may de-prioritize cervical cancer screening, there are significant opportunities for integration into longer-term trends towards universal health coverage, self-care and digital health.

Prevalence and sociodemographic correlates of anogenital Human Papillomavirus (HPV) carriage in a cross-sectional, multi-ethnic, community-based Asian male population

Background

Addressing the burden of HPV-associated diseases among men is increasingly becoming a public health issue. The main objective of this study was to determine HPV prevalence among a healthy community-based Malaysian men.

Method

This was a cross-sectional study that recruited 503 healthy males from 3 community-based clinics in Selangor, Malaysia. Genital and anal samples were collected from each participant for 14 high risk and 2 low risk HPV DNA detection and genotyping. All participants responded to a set of detailed sociodemographic and sexual behaviour questionnaire.

Results

The median age at enrolment was 40 years old (IQR: 31–50). The anogenital HPV6/11 prevalence was 3.2% whereas high risk HPV prevalence was 27.1%. The genital HPV prevalence for HPV6/11 was 2.9% while high risk HPV was 18.8%. HPV6/11 prevalence in the anal canal was 1.6% and high risk HPV was 12.7%. HPV 18 was the most prevalent genotype detected in the anogenital area. There was a significant independent association between genital and anal HPV infections.

Conclusion

Anogenital HPV infection is common among Malaysian men. These findings emphasize the ubiquity of HPV infection and thus the value of population-wide access to HPV prevention.

Association of Vaginal Microbiota With the Genitourinary Syndrome of Menopause Across Reproductive Stages

The genitourinary syndrome of menopause (GSM) is a collection of signs and symptoms related to estrogen decline that involves physical changes to the vulva, vagina, and lower urinary tract. GSM signs and symptoms may occur during any reproductive stage but are most common during menopause. Vaginal microbiota, particularly Lactobacillus spp., protect the female genital tract from multiple conditions; however, Lactobacillus spp. abundance declines during menopause. We aimed to determine the longitudinal association of vaginal microbiota with GSM signs and symptoms across reproductive stages. In a two-year cohort study comprising 750 women aged 35-60 years who contributed 2111 semiannual person-visits, low-Lactobacillus spp. vaginal microbiota communities were observed at 21.2% (169/798), 22.9% (137/597), and 49.7% (356/716) of person-visits among pre-, peri-, and post-menopausal women, respectively (p<.001). After covariate adjustment, low-Lactobacillus spp. communities characterized by high Atopobium and Megasphaera relative abundance were associated with vulvovaginal atrophy relative to high-Lactobacillus spp. communities dominated by L. crispatus (OR[Odds Ratio]=3.04, 95% Confidence Interval[CI]=1.02-9.06) among post-menopausal, but not among peri- or pre-menopausal women. Also, post-menopausal women with low-Lactobacillus spp. communities reported decreased libido (OR=1.79, 95%CI=1.04-3.12) and vaginal dryness (OR=1.61, 95%CI=0.89-2.90) more frequently than their counterparts with high-Lactobacillus spp. communities, but not among peri- or pre-menopausal women (p for interaction<.05). Specifically, low-Lactobacillus spp. communities characterized by high Atopobium and Megasphaera relative abundance were related to both decreased libido (OR=2.82, 95%CI=1.11-7.14) and vaginal dryness (OR=3.50, 95%CI=1.18-10.44) compared with high-Lactobacillus spp. communities dominated by L. gasseri/L. jensenii. Vaginal microbiota, particularly Lactobacillus spp., and menopause may synergistically influence GSM.

The Acceptability and Preference of Vaginal Self-sampling for Human Papillomavirus (HPV) Testing among a Multi-ethnic Asian Female Population

Vaginal self-sampling for human papillomavirus (HPV) testing can potentially increase cervical screening coverage. This study aimed to investigate the acceptability of vaginal self-sampling for HPV testing and factors that might influence a woman's preference for this as a cervical screening method. This was a cross-sectional study that recruited 725 women from the urban and suburban areas of Selangor, Malaysia. All study participants were instructed to self-collect vaginal sample using a dry flocked swab before responding to a detailed questionnaire documenting their experience and preference for self-sampling. Most of the study participants (>80%) perceived vaginal self-sampling as easy, convenient, not embarrassing, comfortable, and were confident in performing the test. This suggests high acceptability toward vaginal self-sampling for HPV testing. Of the 725 women, 83% preferred self-sampling HPV testing over healthcare personnel sampling HPV testing and Pap test. Women with higher household income and full-time employment status were more likely to prefer self-sampling. Those who had not undergone Pap test also expressed preference for self-sampling HPV testing. Convenience and women's confidence in performing a vaginal self-sampling for HPV testing were the independent key factors that influenced the preference for self-sampling method. Vaginal self-sampling for HPV testing is highly acceptable among Malaysian women. It is the preferred choice as a primary cervical screening method and serves as an alternative to healthcare-acquired sample for Pap test. PREVENTION RELEVANCE: Organized cervical cancer screening remains unachievable in many countries. Self-sampling HPV testing is an evidence-based method that can remove barriers to cervical screening. This is particularly important for developing countries in order to achieve the WHO global strategy to accelerate cervical cancer elimination.

Understanding Barriers to Cervical Screening Follow-Up and Treatment Compliance in Malaysia: A Qualitative Study of Provider Perspectives

Background: Cervical cancer is a leading cause of women mortality in Malaysia. In Malaysia, system of care remain fragmented despite the increased uptake of cervical screening. Thus, it is important to better understand factors that affect loss to follow-up and treatment along the care continuum. The ability of a patient to attend a cervical screening clinic, to return for possible treatment, and to return to clinic for follow-up evaluation (“the patient factor”) is a major component to the success of a screening program. Women diagnosed with early or local (stage 1) cervical cancer have a 92% chance of survival 5 years after diagnosis whereas survival rates decrease to 17% for women with late cancer diagnoses. Due to this, a better understanding of barriers to cervical cancer treatment can inform initiatives to address therapeutic delays, which is vitally important to providing optimal care. Aim: To explore, from the perspectives of healthcare professionals, the perceived barriers of cervical screening follow-up and treatment compliance in Malaysia. Methods: In-depth semistructured interviews with 45 government health clinic staffs comprise of clinicians, nurses, front desk staffs, medical laboratory technicians and IT support engineers were conducted from 5 government health clinics in Petaling District. Qualitative content analysis through an inductive approach was used to identify barriers of cervical cancer care continuum and treatment compliance in public health clinics settings. Results: Participants identified various potential barriers to seeking follow-up care and treatment after receiving a positive Pap test results or invalid test results at 2 levels: the structural level, and the patient level. Long waiting time, lack of transport to healthcare providers, fear of treatment, poor documentation, absence of cervical screening registry, as well as unsystematic referral or treatment procedures are some of the major reasons affecting follow-up and treatment compliance. Conclusion: The results highlight the need of structural and personal interventions that eliminate barriers to follow-up and treatment compliance along the care continuum.

Healthcare Providers´ Views on Cervical Screening: A Qualitative Study of Barriers to Cervical Screening in Malaysia

Background: Cervical cancer is the third most common cancer affecting Malaysian women despite being highly preventable through screening. A national cervical cancer screening program has been established since 1969 to ensure early detection of cervical cancer. Nonetheless, the prevalence of cervical cancer in Malaysia remains high. Malaysia has been offering Pap tests for free in community health clinics since 1995, however only 47.3% of women have been screened. It has also been reported that nearly 40% of patients with cervical cancer presented at advanced stages of the disease. Government community healthcare professionals are the main stakeholders in the national cervical screening program. Therefore, understanding these healthcare professionals’ perspective of barriers associated with underutilization of cervical cancer screening is key to increase overall screening uptake. Aim: This study aimed to explore healthcare professionals’ views on perceived barriers to cervical screening in Malaysia. Methods: Qualitative in-depth semistructured interviews were carried out with 44 primary healthcare professionals consisting of family medicine specialists (N = 5), medical officers (N = 9), matrons and nurses (N = 20), laboratory technician (N = 5), registration staff and IT technicians (N = 5) involved in the cervical screening program at 5 different urban government healthcare clinics in Petaling district. The interviews were transcribed verbatim and analyzed using a thematic analysis approach. Results: Themes emerged were individual and system barriers. Individual barriers include knowledge/risk perception (lack of knowledge and awareness of cervical screening, low perceived risk), distress (Pap test is embarrassing or painful, previous negative Pap test experience and fear of a cancer diagnosis) and coping skills (remembering the appointment, managing responsibilities such as getting child care/elder care/coverage at work, ability to get transportation), social-cultural barrier (family support); while system barriers highlight the long waiting time for cervical screening, poor documentation, no national call-recall system, patient overload, lack of resources and manpower, lack of educational materials and problems with opportunistic screening. Conclusion: Sustainable screening interventions require approaches that address and resolve both individual and system barriers, such as exploring new methods and delivery of cervical screening, and providing education for the public and healthcare providers.

Prevalence and sociodemographic correlates of cervicovaginal human papillomavirus (HPV) carriage in a cross-sectional, multiethnic, community-based female Asian population

Objectives

Cervical cancer is a largely preventable disease, and the strategic implementation of a cervical cancer prevention programme is partly dependent on the impact of human papillomavirus (HPV) infection interpreted within the context of the country’s sociodemographic attributes. The objective of this study is to determine the prevalence of cervicovaginal HPV infection among a healthy, community-based, multiethnic Malaysian population. The HPV prevalence was subsequently correlated to the individual’s sociodemographics and sexual/reproductive history. Of significance, the observed prevalence captured was in a birth cohort not included in the national school-based HPV vaccination programme.

Methods

This was a cross-sectional study where 1293 healthy women aged between 18 and 60 years were recruited via convenience sampling from five community-based clinics in Selangor, Malaysia. Cervicovaginal self-samples were obtained and DNA was extracted for HPV detection and genotyping. A comprehensive questionnaire was administered to determine the sociodemographics and behavioural patterns of participants.

Results

The median age at enrolment was 37 years old (IQR: 30–47). In total, 86/1190 (7.2%) of the samples collected were positive for HPV infection, with the highest HPV prevalence (11.9%) detected in the subgroup of 18–24 years old. The top three most prevalent HPV genotypes were HPV 16, 52 and 58. The independent risk factors associated with higher rates of HPV infection included Indian ethnicity, widowed status and women with partners who are away from home for long periods and/or has another sexual partner.

Conclusions

The overall prevalence of HPV infection in this Malaysian multiethnic population was 7.2%, with 6.5% being high-risk genotypes. The top three most common high-risk HPV types were HPV 16, 52 and 58. This information is important for the planning of primary (HPV vaccination) and secondary (screening) cervical cancer prevention programmes in Malaysia.

Oral sampling methods are associated with differences in immune marker concentrations

OBJECTIVE

To determine whether the concentration and distribution of immune markers in paired oral samples were similar.

STUDY TYPE

Clinical research.

STUDY DESIGN

Cross-sectional study.

METHODS

Paired saliva and oral secretions (OS) samples were collected. The concentration of immune markers was estimated using Luminex multiplex assay (Thermo Fisher Scientific, Waltham, MA). For each sample, the concentration of respective immune markers was normalized to total protein present and log-transformed. Median concentrations of immune markers were compared between both types of samples. Intermarker correlation in each sampling method and across sampling methods was evaluated.

RESULTS

There were 90 study participants. Concentrations of immune markers in saliva samples were significantly different from concentrations in OS samples. Oral secretions samples showed higher concentrations of immunoregulatory markers, whereas the saliva samples contained proinflammatory markers in higher concentration.

CONCLUSION

The immune marker profile in saliva samples is distinct from the immune marker profile in paired OS samples.

LEVEL OF EVIDENCE

2b. Laryngoscope, 128:E214-E221, 2018.

A Methodology and Application for Statistical Polarization in the Immune Response

Polarization in the CD4+ mediated T-helper cell immune response is a very well characterized phenomenon in immunology; towards either Th1, Th2, or Th17 pathways. However, to-date, this concept has neither been developed nor demonstrated in a robust statistical framework. In this study, we provide a novel statistical methodology to facilitate the idea of polarization within a multivariate setting, and apply it to luminal fluid cytokine data of 90 women from the Peruvian Amazon. The panel of cytokines and chemokines for this study were assayed using separate BioRad Multiplex Array kits. In our application, we show that soil transmitted helminth (STH) infection induces statistically significant Th2 polarization in the female genital tract.

To provide statistical evidence of Th2 polarization in STH-infected women at the cervix, we compare the clustering of cytokines among STH-infected versus STH-uninfected women while examining the shift in the strength of correlation for Th2 cytokines with IL-4, which is seen as a central Th2 cytokine. The proposed statistical test is one that tests if, significantly, k&gt;1 for f(L1)=f(L2) where L1 and L2 are the loadings in the principal component analysis (PCA) framework for the STH-infected and STH-infected groups respectively.

The proposed method is a confirmatory one and could be supported by visual representation of the Th polarization through heat maps. It has the potential to become the reference or gold standard when studying the polarization phenomenon in immunology as it tailors the clinical characteristics and mechanisms associated with the entire panel of cytokines and chemokines in the context of a system.

Population-based prevalence of cervical infection with human papillomavirus genotypes 16 and 18 and other high risk types in Tlaxcala, Mexico

BACKGROUND

Cervical cancer remains an important cause of cancer mortality for Mexican women. HPV 16/18 typing may help to improve cervical cancer screening. Here we present the prevalence of high-risk human papillomavirus (hrHPV) including HPV16 and HPV18 from the FRIDA (Forwarding Research for Improved Detection and Access) population.

METHODS

Beginning in 2013, we recruited 30,829 women aged 30-64 in Tlaxcala, Mexico. Cervical samples were collected and tested for 14 hrHPV genotypes (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68). We used logistic regression to estimate odds ratios with 95 % confidence intervals for hrHPV infections according to putative risk factors.

RESULTS

Prevalence of infection with any of the 14 hrHPV types was 11.0 %. The age-specific prevalence of all hrHPV formed a U-shaped curve with a higher prevalence for women aged 30-39 and 50-64 than women aged 40-49. Across all age groups, 2.0 % of women were positive for HPV16 and/or HPV18 (HPV16/18), respectively. HPV16/18 prevalence also showed a U-shaped curve with increased prevalence estimates for women aged both 30-39 and 60-64. Both prevalence curves had a significant quadratic age coefficient. Infections with hrHPV were positively associated with an increased number of lifetime sexual partners, a history of sexually transmitted disease, being unmarried, use of hormonal contraception, having a history of smoking and reported condom use in the multivariate model.

CONCLUSIONS

The FRIDA population has a bimodal distribution of both hrHPV and HPV16/18 positivity with higher prevalences at ages 30-39 and 60-64. These findings will help to evaluate triage algorithms based on HPV genotyping.

TRIAL REGISTRATION

The trial is registered with ClinicalTrials.gov, number NCT02510027 .

Attitudes and factors affecting acceptability of self-administered cervicovaginal sampling for human papillomavirus (HPV) genotyping as an alternative to Pap testing among multiethnic Malaysian women

OBJECTIVE

The objective of this study was to determine the attitudes and acceptability of self-administered cervicovaginal sampling compared with conventional physician-acquired Papanicolaou (Pap) smear among multiethnic Malaysian women.

METHOD

A cross-sectional study was carried out via interviewer-administered surveys from August 2013 through August 2015 at five government-run, urban health clinics in the state of Selangor. Subjects were participants from an ongoing community-based human papillomavirus (HPV) prevalence study who answered a standard questionnaire before and after self-sampling. The cervicovaginal self-sampling for HPV genotyping was performed using a simple brush ('Just for Me'; Preventive Oncology International, Hong Kong). Detailed data on sociodemographics, previous Pap smear experience, and attitudes towards self-administered cervicovaginal sampling were collected and analysed. Acceptability was inferred using a five-item Likert scale that included six different subjective descriptives: experience, difficulty, convenience, embarrassment, discomfort or pain, and confidence in collecting one's own sample.

RESULTS

Of the 839 participants, 47.9% were Malays, followed by 30.8% Indians, 18.8% Chinese and 2.5% from other ethnicities. The median age of the participants was 38 years (IQR 30-48). Some 68.2% of participants indicated a preference for self-sampling over the Pap test, with 95% indicating willingness to follow-up a positive result at the hospital. Age, ethnicity and previous Pap test experience were significant independent factors associated with preference for self-sampling. The older the individual, the less likely they were to prefer self-sampling (adjusted OR 0.94, 95% CI 0.90 to 0.98). The Chinese were less likely to prefer self-sampling (72.6%) than the Malays (85.1%) (adjusted OR 0.57, 95% CI 0.33 to 0.98, p=0.004). Participants who had never undergone a Pap smear were also more likely to prefer self-sampling (88.5%) than women who had undergone a previous Pap (80.9%) (adjusted OR 0.06, 95% CI 0.35 to 0.87).

CONCLUSIONS

Overall, urban Malaysian women from multiethnic backgrounds found self-sampling to be an acceptable alternative to Pap smear.

Modeling cytokines and chemokines through a rooted correlation network

Several studies have investigated the role of cytokines/chemokines in infection and chronic and autoimmune diseases using different statistical models. Generally, only two mediators are evaluated at a time, by comparing group-specific mean concentration differences. Restricted pairwise analysis from a large array of markers which inherently operate at a systems level to regulate immune response ignores important inter-correlation structures, compromising clinical and epidemiological inference. We propose the use of a rooted correlation network as a novel statistical method which allows group-specific comparisons of a panel of soluble immune markers while adjusting for the interaction complexity.

We examined soluble immune markers in luminal fluid samples from 90 HPV infected female participants with and without soil transmitted helminth (STH) co-infection in Peru. We constructed a lower triangular correlation matrix using Spearman’s correlation with Sidak adjustment for both the STH-infected and -uninfected women. Rooted correlation network was constructed for the cytokines and chemokines that were insignificant in the non-helminth group but became significant in the helminth one. The generated cytokine network demonstrated statistically significant association of Th2 pathway cytokines with the canonical Th2 cytokine IL-4. Using this new statistical model, we demonstrate that the female genital tract of STH-infected women reveals polarization towards Th2 immune response (IL-25, IL-21, IL-5, IL-10, IL-8, and IL-31) in comparison to STH-uninfected women, which was not easily recognizable when using standard bivariate methods with multiple comparisons.

Triage strategies in cervical cancer detection in Mexico: methods of the FRIDA Study

OBJECTIVE

This paper describes the study design and baseline characteristics of the study population, including the first 30 829 women who enrolled in the Forwarding Research for Improved Detection and Access for Cervical Cancer Screening and Triage (FRIDA Study). This is a large population based study that is evaluating the performance and cost-effectiveness of different triage strategies for high-risk HPV (hrHPV) positive women in Mexico.

MATERIALS AND METHODS

The target population is more than 100 000 women aged 30 to 64 years who attend the Cervical Cancer Screening Program in 100 health centers in the state of Tlaxcala, Mexico. Since August 2013, all women in the region have been invited to enroll in the study. The study participants are evaluated to determine hrHPV infection using the Cobas 4800 HPV test. The HPV-16/18 genotyping and cytology triage strategies are performed as reflex tests in all hrHPV-positive participants. Women with a positive HPV-16/18 test and/or abnormal cytology (atypical squamous cells of undetermined significance or worse, ASCUS+) are referred for colposcopy evaluation, where a minimum of four biopsies and an endocervical sample are systematically collected. Histologic confirmation is performed by a standardized panel of pathologists.

RESULTS

Among the 30 829 women who have been screened, the overall prevalence of hrHPV is 11.0%. The overall prevalence of HPV16 and HPV18 are 1.5% and 0.7%, respectively. Cytological abnormalities (ASCUS+) were detected in 11.8% of the hrHPV-positive women. A total of 27.0% (920/3,401) of the hrHPV-positive women were referred to colposcopy because of a positive HPV16/18 test and/or abnormal reflex cytology, (31.6% had only ASCUS+, 53.6% were HPV16/18 positive with a normal cytology result, and 9.5% were positive to both triage tests).

CONCLUSION

The results of this study will help policy makers and health service providers establish the best practices for triage in cervical cancer screening in Mexico and other countries.

Correlates of anal sex roles among Malay and Chinese MSM in Kuala Lumpur, Malaysia

Identifying roles for anal sex is an important issue for populations of MSM. We describe the prevalence of identifying as being 'top', 'bottom', 'versatile', or 'don't know/not applicable' among Malay and Chinese MSM in Kuala Lumpur, Malaysia, and behavioural outcomes according to these labels for sexual role identity. Data analysis was conducted on a survey administered during weekly outreach throughout Kuala Lumpur in 2012. Pearson's Chi square tests were used to compare demographic and behavioural characteristics of MSM who reported roles for anal sex. Binary logistic regression was used to explore the odds of behavioural outcomes among MSM who identified as 'bottom', 'versatile,' and 'don't know' compared to MSM who reported that 'top' was their sexual role. Labels for anal sex roles were significantly associated with condom use for last anal sex. Among MSM who used labels for anal sex roles, MSM who identified as 'bottom' had highest level of not using condoms for last anal sex (24.1%, p = .045). In binary logistic regression model, identifying as 'top' was significantly associated with reporting using a condom during last anal sex and reported consistent condom use for anal sex in the past six months (p = .039 and .017, respectively). With regard to sexual role identity, some MSM may be a part of a special subgroup of at-risk men to be targeted. Future research should evaluate the origins, meanings, and perceptions of these labels, and the developmental process of how these MSM identify with any of these categories. Research should also uncover condom use decision making with regard to these labels for sexual positioning.

Awareness and utilization of HIV services of an AIDS community-based organization in Kuala Lumpur, Malaysia

Summary

In Malaysia, homosexuality is illegal; little is known about access to HIV prevention services among Malaysian men who have sex with men (MSM). We analysed PT Foundation outreach data to describe the profiles among MSM who accessed PT Foundation services and to examine factors associated with being aware of PT Foundation and having visited the organization. A survey was administered during weekly outreach throughout Kuala Lumpur from March–December 2012. Pearson's Chi square tests were used to compare demographic and behavioural characteristics of participants who were and were not aware of the PT Foundation. Binary logistic regression was used to identify correlates of MSM visiting the PT Foundation among those who had heard of the organization. Of 614 MSM, this study found significantly higher awareness of the PT Foundation among MSM who perceived they had “good” HIV knowledge ( p = .026) and participants who reported always using condoms ( p = .009). MSM who reported being paid for sex were 2.81 times as likely to visit the PT Foundation compared to men who did not. A subgroup of MSM known to be at high risk for HIV infection is accessing prevention services. Future studies should uncover motivations and barriers of accessing these services among MSM in Malaysia.

Human papillomavirus and the risk of Barrett's esophagus

Human papillomavirus (HPV) is strongly associated with squamous esophageal cancer. The potential role of HPV in Barrett's esophagus (BE) has been examined but remains unclear. The aim of the study was to determine the prevalence of HPV in esophageal and gastric tissues obtained from patients with and without BE. We designed a cross-sectional study was conducted with prospective enrollment of eligible patients scheduled for esophagogastroduodenoscopy (EGD). All participants had biopsies of endoscopic BE, squamous-lined esophagus, and stomach. Immunohistochemistry (IHC) on formalin-fixed and paraffin-embedded tissue was conducted using monoclonal antibodies. Polymerase chain reaction (PCR) for HPV was performed on DNA extracted from esophageal biopsies snapped frozen within 30 minutes after endoscopic capture. The Roche HPV Linear Array Assay with PGMY primers that has high sensitivity for detecting 37 types of HPV was used. A total of 127 subjects were included: 39 with definitive BE had IHC done on samples from non-dysplastic BE, squamous esophagus, gastric cardia, and gastric body; and 88 control patients without BE had IHC done on squamous esophageal samples, gastric cardia, and gastric body. HPV was not detected in any of the samples in either group. For confirmation, HPV DNA PCR was performed on randomly selected samples from 66 patients (both esophagus and BE from 13 patients with BE, and 53 esophagus from patients without BE); no sample had HPV DNA detected via PCR in the presence of adequate quality control. HPV infection does not play a role in the formation of non-dysplastic Barrett's esophagus in men in the United States.

New technologies and procedures for cervical cancer screening

The clearly higher sensitivity and reproducibility of human papillomavirus (HPV) DNA testing for high-grade cervical intraepithelial neoplasia (CIN) has led to widespread calls to introduce it as the primary screening test. The main concern has been its lower specificity, due to the fact that it cannot separate transient from persistent infections, and only the latter are associated with an increased risk of high-grade CIN and cancer. Thus, even proponents of HPV testing generally only recommend it for women over the age of 30 years (or in some cases 35 years). If HPV testing is to reach its full potential, new approaches with better specificity are needed, either as triage tests for HPV positive women or, if the high sensitivity of HPV DNA testing can be maintained, as alternate primary screening modalities. Approaches that may useful in this regard, especially as triage tests, include HPV typing, methylation (and consequent silencing) of host and viral genes, and new cytologic methods, such as p16(INK4a) staining, which attempt to identify proliferating cells. At an earlier stage of development are direct methods based on detection of HPV E6 or E7 proteins. Recent progress and current status of these methods is discussed in this chapter. The current status of visual inspection (VIA and VILI) methods is also surveyed and progress on self-sampling is reviewed. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Male circumcision reduces penile high-risk human papillomavirus viral load in a randomised clinical trial in Rakai, Uganda

OBJECTIVES

Male circumcision reduces penile high-risk human papillomavirus (HR-HPV) prevalence in randomised trials. The goal of this study was to examine the effect of circumcision on HPV viral load among HPV-infected men in a randomised trial of male circumcision.

METHODS

In a randomised trial to assess the efficacy of circumcision on HIV acquisition in Rakai, Uganda, HIV-negative men were randomised to immediate (intervention) or delayed (control) circumcision and followed over 24 months. We performed quantitative-PCR HPV viral load assays on penile swabs which tested positive by Linear Array (LA) for six HR-HPV genotypes and estimated viral load in the remaining types by LA signal strength.

RESULTS

At 24 months, circumcision intervention arm men infected with one of the six selected HR-HPV genotypes had a lower viral load and significantly reduced HR-HPV high LA band intensity (PRR=0.61, 95% CI 0.43 to 0.86) compared to infected men in the control arm of the trial. The decreased viral load associated with circumcision was seen among HPV infections acquired after enrolment but not among infections that persisted from trial enrolment to 24 months (p=0.80).

CONCLUSIONS

The decreased penile HR-HPV shedding observed among HPV-infected circumcised men may help to explain the protective association observed between circumcision and reduced acquisition of HR-HPV in female partners.

Randomized trial of HPV4 vaccine assessing the response to HPV4 vaccine in two schedules among Peruvian female sex workers

Two hundred female sex workers (FSWs) in Lima, Peru were randomized to receive HPV4 vaccine in the standard (0, 2, 6 months) or a modified schedule (0, 3, 6 months). One hundred and eighty four (92%) participants completed 3 doses of vaccine. Baseline seropositive rates were 58% for HPV6, 22.5% for HPV11, 41.5% for HPV16, and 13% for HPV18. The final geometric mean antibody titer (GMT) following vaccination was significantly greater for women who were seropositive at baseline compared to seronegative women: HPV6 (GMT ratio=2.3, p<0.01), HPV11 (GMT ratio=2.7, p<0.01), HPV16 (GMT ratio=1.3, p=0.04), and HPV18 (GMT ratio=2.4, p<0.01). Antibody titers in the modified schedule were not inferior to those in the standard schedule, suggesting the modified schedule may be paired with required STD visits. Although all women benefit from vaccination, administration at a younger age and before sexual debut is needed to achieve maximum protection from vaccine.

Cervical pap screening cytological abnormalities among HIV-infected adolescents in the LEGACY cohort

OBJECTIVES

To determine the prevalence of cervical Pap screening (CPAP-S), identify factors associated with CPAP-S, and explore risk factors for abnormal cervical cytology in female adolescents with perinatally and behaviorally acquired HIV infection.

DESIGN

Cross-sectional.

SETTING

LEGACY is a national observational cohort chart review study of 1478 HIV-infected persons (<age 24 years) managed in 22 HIV specialty clinics in the United States.

PARTICIPANTS

Sexually active females aged 13-24 years in the LEGACY cohort.

MAIN OUTCOME MEASURES

CPAP-S and abnormal cervical cytology.

RESULTS

Of 231 sexually active female LEGACY participants 13-24 years of age 49% had documentation of CPAP-S between 2001 and 2006. Fifty-eight percent of 113 cervical tests were abnormal (2% high-grade). In multivariable analysis, perinatal HIV infection and black race were associated with decreased likelihood of CPAP-S (adjusted prevalence ratio [APR] 0.66, 95% CI 0.45-0.96 and APR 0.74, 95% CI 0.56-0.96, respectively). Presence of any sexually transmitted infection (STI) was independently associated with increased likelihood of CPAP-S (APR 1.56, 95% CI 1.21, 2.02). CD4+ T-lymphocyte count <200 cells/mL and previous STI diagnosis were independently associated with increased likelihood of abnormal cervical cytology (APR 2.19, 95% CI 1.26-3.78 and APR 1.94, 95% CI 1.29-2.92, respectively).

CONCLUSIONS

Among sexually active HIV-infected adolescent females, prevalence of CPAP-S was low and cytology was abnormal in more than half of Pap smears. Perinatally HIV-infected, sexually active females were less likely to undergo CPAP-S than their behaviorally HIV-infected counterparts. Interventions targeted at HIV-infected adolescents and care providers are needed to improve CPAP-S in HIV-infected young women, especially those with perinatally acquired HIV infection.

Clustering of human papillomavirus (HPV) types in the male genital tract: the HPV in men (HIM) study

OBJECTIVE

To evaluate clustering patterns of prevalent infection with multiple human papillomavirus (HPV) types in 3677 men from the HPV in Men (HIM) study.

METHODS

HPV testing was performed in samples combined from the glans penis/coronal sulcus, the shaft, and the scrotum by Linear Array methodology. Linear Array uses a mixed probe to assess HPV52 positivity, which limits the assay's ability to determine HPV52 status in the presence of HPV33, 35, or 58. Logistic regression was used to model type-specific HPV positivity, adjusted for age, study area, lifetime number of sexual partners, and specific HPV type prevalence. Participant-level random effects were added to represent unobservable risk factors common to all HPV types.

RESULTS

The observed-to-expected ratio for infections with ≥ 3 types was 1.09 (95% credible interval, 1.04-1.14). For the majority of 2-type combinations, no evidence was found of a significant departure of the observed from the expected number. An apparent clustering of HPV52 with HPV35 or 58 was observed, because of limitation in the ability of Linear Array to define HPV52 positivity.

CONCLUSIONS

Our study showed that, despite obvious anatomical differences, HPV coinfections do seem to occur at random in the male external genitalia as in the female cervix.

Prognostic utility of anti-EBV antibody testing for defining NPC risk among individuals from high-risk NPC families

PURPOSE

Epstein-Barr virus (EBV) infection and a family history of nasopharyngeal carcinoma (NPC) are associated with NPC risk. We examined the risk associated with EBV markers and their clinical utility to identify NPC susceptibles within high-risk NPC families.

EXPERIMENTAL DESIGN

We evaluated antibody titers against viral capsid antigen (VCA) IgA, EBV nuclear antigen-1 (EBNA1) IgA, and DNase among unaffected relatives of NPC cases from 358 multiplex families in Taiwan. Incident NPC cases were identified via linkage to the National Cancer Registry. Clinical examinations of 924 individuals were also done to identify occult, asymptomatic NPC. Baseline EBV serology was used to estimate NPC risk using rate ratios with 95% CI. Associated sensitivity/specificity and receiver operating characteristic (ROC) curves were calculated.

RESULTS

A total of 2,444 unaffected individuals with 15,519 person-years (6.5 years median follow-up) yielded 14 incident NPC cases (nearly 11 times the general population rate). The absolute rate of NPC among anti-EBV EBNA1 IgA seropositives using a standard positivity cutoff versus an optimized cutoff point defined by ROC analyses was 265/100,000 person-years with a 4.7-fold increased risk of NPC (95% CI: 1.4-16) and 166/100,000 person-years with a 6.6-fold increase (95% CI: 1.5-61), respectively. Sensitivity and specificity using the optimized positivity cutoff points were 85.7% and 51.2%, respectively. It is estimated that active evaluation of 49% of individuals from high-risk NPC families seropositive for this marker could lead to earlier detection of up to 86% of NPC cases. Risks associated with the other three EBV markers were weaker.

CONCLUSIONS

Future efforts are needed to identify susceptibility markers among high-risk NPC families that maximize both sensitivity and specificity.

Human papillomavirus and cervical neoplasia among female sex workers in Madagascar

INTRODUCTION

Human papillomavirus (HPV) prevalence and type distribution were estimated among 90 female sex workers (FSWs) aged 18 to 58 years in Antananarivo, Madagascar.

METHODS

A total of 90 FSWs aged 18 to 58 years in Antananarivo, Madagascar, were included in this study. Information on sexual and behavioral characteristics was obtained via a questionnaire. Exfoliated cervical cell specimens were collected for conventional cytologic examination and HPV DNA testing by polymerase chain reaction. The prevalence rates of HPV DNA and their corresponding 95% confidence intervals were stratified into the following 3 age groups: younger than 25, 25 to 34, and 35 years or older. To assess the association between HPV DNA positivity and sociodemographic and sexual behavioral factors, age-adjusted odds ratios and 95% confidence intervals were calculated using unconditional logistic regression.

RESULTS

The HPV prevalence in exfoliated cervical cell specimens was 36.7%. The most common HPV types found were HPV-52 (11.1%), HPV-31 and -39 (each at 5.6%), and HPV-16 and -83 (each at 3.3%). The prevalence of low-grade squamous intraepithelial lesions was 3.3%, and that of atypical squamous cells of undetermined significance was 18.9%. No high-grade lesion was found. Although associations were imprecise, the HPV prevalence was higher among women who reported younger age at the first intercourse, contraceptive use, a history of cervical lesions, and no history of condom use.

DISCUSSION

The prevalence rates of HPV and cervical lesions among FSWs in Madagascar appear higher than among FSW populations from other African countries with a relatively higher population-based prevalence of human immunodeficiency virus infection.

No role for human papillomavirus in esophageal squamous cell carcinoma in China

Certain regions of China have high rates of esophageal squamous cell carcinoma (ESCC). Previous studies of human papillomavirus (HPV), a proposed causal factor, have produced highly variable results. We attempted to evaluate HPV and ESCC more definitively using extreme care to prevent DNA contamination. We collected tissue and serum in China from 272 histopathologically-confirmed ESCC cases with rigorous attention to good molecular biology technique. We tested for HPV DNA in fresh-frozen tumor tissue using PCR with PGMY L1 consensus primers and HPV16 and 18 type-specific E6 and E7 primers, and in formalin-fixed paraffin-embedded tumor tissue using SPF(10) L1 primers. In HPV-positive cases, we evaluated p16(INK4a) overexpression and HPV E6/E7 seropositivity as evidence of carcinogenic HPV activity. beta-globin, and thus DNA, was adequate in 98.2% of the frozen tumor tissues (267/272). Of these, 99.6% (95% confidence interval (CI) = 97.9-100.0%) were negative for HPV DNA by PGMY, and 100% (95% CI = 98.6-100%) were negative by HPV16/18 E6/E7 PCR. In the corresponding formalin-fixed paraffin-embedded tumor specimens, 99.3% (95% CI = 97.3-99.9%) were HPV negative by SPF(10). By PGMY, 1 case tested weakly positive for HPV89, a noncancer causing HPV type. By SPF(10), 2 cases tested weakly positive: 1 for HPV16 and 1 for HPV31. No HPV DNA-positive case had evidence of HPV oncogene activity as measured by p16(INK4a) overexpression or E6/E7 seropositivity. This study provides the most definitive evidence to date that HPV is not involved in ESCC carcinogenesis in China. HPV DNA contamination cannot be ruled out as an explanation for high HPV prevalence in ESCC tissue studies with less stringent tissue procurement and processing protocols.

Human papillomavirus vaccine update

With the approval of Gardasil (Merck and Co., Inc., Whitehouse Station, NJ) in June of 2006 and the pending approval of Cervarix (GlaxoSmithKline, London, UK), two prophylactic human papillomavirus (HPV) vaccines will be available for clinical use. Randomized controlled trials have shown that both vaccines are safe and highly effective in preventing persistent infection and lesions caused by HPV 16 and 18--the types responsible for 70% of cervical cancers worldwide. Determining an effective vaccination strategy is now the most pressing issue facing clinicians, parents, public health officials, and policy makers. We discuss the appropriate age of vaccination, vaccine acceptance, implementation strategies in low resource settings, and the future of screening.

Circumcision of HIV-infected men: effects on high-risk human papillomavirus infections in a randomized trial in Rakai, Uganda

In Rakai, Uganda, human immunodeficiency virus (HIV)-positive men were randomized to undergo either immediate circumcision (intervention arm) or delayed circumcision (control arm). Penile swab samples were assayed for high-risk human papillomavirus (HR-HPV) by Roche HPV Linear Array at enrollment and at 24 months (intervention arm, 103 subjects; control arm, 107 subjects). Rate ratios (RRs) of HR-HPV were estimated by Poisson regression. At 24 months, HR-HPV prevalence was found in 57 (55.3%) of 103 subjects in the intervention arm and in 77 (71.7%) of 107 subjects in the control arm (RR, 0.77; 95% confidence interval [CI], 0.62-0.97). Multiple HR-HPV infections were found in 19 (22.4%) of 85 subjects in the intervention arm and in 45 (42.5%) of 106 subjects in the control arm (RR, 0.53; 95% CI, 0.33-0.83). New HR-HPV genotypes were acquired by 34 (42.0%) of 81 subjects in the intervention arm and by 53 (57.0%) 85 subjects in the control arm (RR, 0.74; 95% CI, 0.54-1.01; P = .06). Multiple new HR-HPV genotypes were acquired by 8 (9.9%) of 81 subjects in the intervention arm and by 23 (24.7%) of 93 subjects in the control arm (RR, 0.40; 95% CI, 0.19-0.84; P = .01). Circumcision did not affect the acquisition of single HR-HPV infections (RR, 1.00; 95% CI 0.65-1.53) or clearance of HR-HPV infections (RR, 1.09; 95% CI 0.94-1.27). Circumcision of HIV-positive men reduced the prevalence and incidence of multiple HR-HPV infections.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00124878 .

The gastric cardia is not a target for human papillomavirus-induced carcinogenesis

BACKGROUND

Thousands of people in central Asia die every year from gastric cardia adenocarcinoma (GCA). GCA arises in the transformation zone between the esophagus and the stomach, similar to cervical and oropharyngeal carcinoma, which arise in areas with transformation zone characteristics. The analogous biology of the gastric cardia to the cervix and oropharynx, where human papillomavirus (HPV) is known to cause cancer, raises the possibility that GCA could be a HPV-associated cancer. Given the availability of an effective HPV vaccine and its potential to prevent HPV-associated cancer, we decided to evaluate the prevalence of HPV DNA in GCA.

METHODS

We collected tumor tissue from 144 histopathologically confirmed GCA patients at Yaocun Commune Hospital (Linxian, China), with rigorous attention to prevent DNA contamination. We tested for the presence of HPV DNA in fresh-frozen tumor specimens using PCR with sensitive L1-, E6-, and E7-based primers.

RESULTS

DNA was adequate, as indicated by beta-globin positivity, in 108 cases. Of these, all (100%; 95% confidence interval, 97-100%) were negative for HPV DNA.

CONCLUSIONS

These results suggest that HPV does not contribute to gastric cardia carcinogenesis in north central China.

IMPACT

Because GCA does not seem to be a HPV-associated cancer, prophylactic HPV vaccination is unlikely to affect rates of GCA in China.

Detection and quantitation of HPV 16 and 18 in plasma of Indian women with cervical cancer

OBJECTIVE

HPV infection is a necessary but insufficient cause of cervical cancer. The significance of HPV DNA in blood however is debatable because of variable detection rates due to the differences in the methodology used. The aim of this study was to detect and quantitate HPV 16 and 18 plasma viremia in women with cervical neoplasia.

METHODS

HPV DNA was detected in cervical tissue using consensus PGMY primers and genotyped using reverse line blot hybridization. HPV 16 and 18 quantitation in tissue and detection and quantitation in plasma was performed using sensitive real time PCRs targeting E6/E7 region of HPV 16/18 genome respectively. Results were correlated with viral loads in corresponding tissue and with clinical disease stage.

RESULTS

Viremia was detected in 56.4% of HPV 16 positive women and 20% of HPV 18 positive women. The prevalence of HPV 16 DNA in plasma increased with advancing disease stage (p=0.001), although HPV 16 absolute plasma viral load was not significantly associated with advancing disease stage (p=0.281). There was no correlation between absolute plasma viral load and viral load in corresponding cervical tissue (Spearman's rho=0.184, p=0.187). The prevalence of HPV 18 viremia and absolute HPV 18 plasma viral load were not associated with advancing disease stage (p=0.620, p=0.508).

CONCLUSION

The presence of HPV 16 in plasma is a marker of advancing cervical disease.

A phase I trial of a human papillomavirus DNA vaccine for HPV16+ cervical intraepithelial neoplasia 2/3

PURPOSE

To evaluate the safety and immunogenicity of a therapeutic human papillomavirus (HPV)16 DNA vaccine administered to women with HPV16+cervical intraepithelial neoplasia (CIN)2/3.

EXPERIMENTAL DESIGN

This phase I trial incorporated the standard '3+3'' dose-escalation design with an additional 6 patients allocated to the maximally tolerated dose. Healthy adult women with colposcopically directed, biopsy-proven HPV16+ CIN2/3 received 3 i.m. vaccinations (0.5, 1, or 3 mg) of a plasmid expressing a Sig-E7(detox)-heat shock protein 70 fusion protein on days 0, 28, and 56, and underwent standard therapeutic resection of the cervical squamocolumnar junction at day 105 (week 15). The safety and immunogenicity of the vaccine and histologic outcome based on resection at week 15 were assessed.

RESULTS

Fifteen patients were evaluable (3 each at 0.5 and 1mg, 9 at 3 mg). The vaccine was well tolerated: most adverse events were mild, transient injection-site discomfort; no dose-limiting toxicities were observed. Although HPVE7-specific T-cell responses to E7 detected by enzyme-linked immunospot assays (IFN-gamma) were of low frequency and magnitude, detectable increases in response subsequent to vaccination were identified in subjects in the second and third cohorts. Complete histologic regression occurred in 3 of 9 (33%; 7-70% confidence interval) individuals in the highest-dose cohort. Although the difference is not significant, it is slightly higher than would be expected in an unvaccinated cohort (25%).

CONCLUSIONS

This HPV16 DNA vaccine was safe and well tolerated. Whereas it seems possible to elicit HPV-specific T-cell responses in patients with established dysplastic lesions, other factors are likely to play a role in lesion regression.

A phase I trial of a human papillomavirus DNA vaccine for HPV16+ cervical intraepithelial neoplasia 2/3

PURPOSE

To evaluate the safety and immunogenicity of a therapeutic human papillomavirus (HPV)16 DNA vaccine administered to women with HPV16+cervical intraepithelial neoplasia (CIN)2/3.

EXPERIMENTAL DESIGN

This phase I trial incorporated the standard '3+3'' dose-escalation design with an additional 6 patients allocated to the maximally tolerated dose. Healthy adult women with colposcopically directed, biopsy-proven HPV16+ CIN2/3 received 3 i.m. vaccinations (0.5, 1, or 3 mg) of a plasmid expressing a Sig-E7(detox)-heat shock protein 70 fusion protein on days 0, 28, and 56, and underwent standard therapeutic resection of the cervical squamocolumnar junction at day 105 (week 15). The safety and immunogenicity of the vaccine and histologic outcome based on resection at week 15 were assessed.

RESULTS

Fifteen patients were evaluable (3 each at 0.5 and 1mg, 9 at 3 mg). The vaccine was well tolerated: most adverse events were mild, transient injection-site discomfort; no dose-limiting toxicities were observed. Although HPVE7-specific T-cell responses to E7 detected by enzyme-linked immunospot assays (IFN-gamma) were of low frequency and magnitude, detectable increases in response subsequent to vaccination were identified in subjects in the second and third cohorts. Complete histologic regression occurred in 3 of 9 (33%; 7-70% confidence interval) individuals in the highest-dose cohort. Although the difference is not significant, it is slightly higher than would be expected in an unvaccinated cohort (25%).

CONCLUSIONS

This HPV16 DNA vaccine was safe and well tolerated. Whereas it seems possible to elicit HPV-specific T-cell responses in patients with established dysplastic lesions, other factors are likely to play a role in lesion regression.

Human papillomavirus genotypes associated with cervical neoplasia in India

The aim of this study was to determine the prevalence of human papillomavirus (HPV) genotypes in tissue with cervical neoplasias in patients from south and east India. Cross-sectional cervical tissue was obtained from 100 patients from south India and 30 patients from east India who had a biopsy for clinically invasive cervical cancer or cervical intraepithelial neoplasia (CIN) in a tertiary care hospital in India. DNA amplification was done with biotinylated PGMY 09/11 primers, and the line blot assay was used to determine the HPV genotype. HPV DNA was detected in 95% of invasive cancers (113/119) and 91% of CINs (10/11). A single HPV type was found in 100 women (77%), and mixed infections were found in 23 women (18%). HPV 16 (60%) and HPV 18 (14%) were the most frequent types, but 16 other types (26, 31, 33, 35, 42, 45, 51, 52, 53, 56, 58, 61, 62, 64, 81, and 82) were also identified. HPV 16 was present in 63% of patients from south India and in 50% of patients from east India, while HPV 18 was present in 12% and 20%, respectively. There are several high-risk HPV types associated with cervical neoplasias of which types 16 and 18 are the most common.