Cost-effectiveness analysis of primary human papillomavirus testing in cervical cancer screening: Results from the HPV FOCAL Trial

The Role of Scientific Research in Human Papillomavirus Vaccine Discussions on Twitter: Social Network Analysis

BACKGROUND

Attitudes toward the human papillomavirus (HPV) vaccine and accuracy of information shared about this topic in web-based settings vary widely. As real-time, global exposure to web-based discourse about HPV immunization shapes the attitudes of people toward vaccination, the spread of misinformation and misrepresentation of scientific knowledge contribute to vaccine hesitancy.

OBJECTIVE

In this study, we aimed to better understand the type and quality of scientific research shared on Twitter (recently rebranded as X) by vaccine-hesitant and vaccine-confident communities.

METHODS

To analyze the use of scientific research on social media, we collected tweets and retweets using a list of keywords associated with HPV and HPV vaccines using the Academic Research Product Track application programming interface from January 2019 to May 2021. From this data set, we identified tweets referring to or sharing scientific literature through a Boolean search for any tweets with embedded links, hashtags, or keywords associated with scientific papers. First, we used social network analysis to build a retweet or reply network to identify the clusters of users belonging to either the vaccine-confident or vaccine-hesitant communities. Second, we thematically assessed all shared papers based on typology of evidence. Finally, we compared the quality of research evidence and bibliometrics between the shared papers in the vaccine-confident and vaccine-hesitant communities.

RESULTS

We extracted 250 unique scientific papers (including peer-reviewed papers, preprints, and gray literature) from approximately 1 million English-language tweets. Social network maps were generated for the vaccine-confident and vaccine-hesitant communities sharing scientific research on Twitter. Vaccine-hesitant communities share fewer scientific papers; yet, these are more broadly disseminated despite being published in less prestigious journals compared to those shared by the vaccine-confident community.

CONCLUSIONS

Vaccine-hesitant communities have adopted communication tools traditionally wielded by health promotion communities. Vaccine-confident communities would benefit from a more cohesive communication strategy to communicate their messages more widely and effectively.

High risk HPV testing for cervical cancer screening in a Puerto Rican population

The Human Papillomavirus (HPV) causes cervical cancer, the fourth most common cause of death in women in the United States (US). Several major screening clinical trials have demonstrated that high risk HPV (HR-HPV) DNA primary screen is more sensitive at determining the risk of cervical intraepithelial neoplasia level 3 or higher (CIN ≥ 3) than cytology alone and is similar to co-testing. In this cross-sectional study, we characterized a Hispanic population of 18,052 women ages 21-70 years with HR-HPV DNA testing and cytology to determine the prevalence of HR-HPV in the population and determine the likelihood of high grade squamous intraepithelial lesion (HSIL). We also compared cytology, HR-HPV DNA testing, and co-testing strategies to determine sensitivity, specificity, positive predictive value, and negative predictive value for HSIL in cervical biopsies. Results show that HR-HPV had a slightly higher sensitivity (94.2% vs 92.3%) compared to cytology for all high-grade disease (CIN2/3).

Clinical efficacy of primary human papillomavirus (HPV) screening with partial genotyping for HPV-16 and HPV-18 subtypes in women from 25 years old

Introduction

Cervical screening programmes differ in the age of women recommended for primary human papillomavirus (HPV) testing. This study aims to determine the clinical efficacy and impact of 14-high-risk HPV DNA testing for women from 25 years old.

Method

This was a retrospective analysis of data collected prospectively from women 25 years or older who attended hospital-based gynaecology clinics for cervical screening. Women with history of cervical neoplasia or abnormal cytology were excluded. High-risk HPV DNA testing with partial genotyping for HPV-16 and HPV-18 were performed on cobas 4800 System (Roche Diagnostics International AG, Rotkreuz, Switzerland). Women tested positive for the 12 other high-risk HPV subtypes (HPV-12 other) had a reflex cytology test. Positive screening included positive for HPV-16 and/or HPV-18, HPV-12 other with cytology abnormalities equal to or greater than atypical squamous cells of undetermined significance, and repeated positive HPV at 12 months. HPV detection and colposcopy referral rates, and detection of high-grade neoplasia were determined.

Results

Of 10,967 women studied, 822 (7.50%) were HPV DNA positive. The overall discharge rate to routine screening according to screening protocol was 93.1%. Colposcopy referral rate was 4.4%. The screening detected 41 cervical intraepithelial neoplasia grade 2+ (CIN2+) (0.37%) and 31 (0.28%) CIN3+. The number of colposcopies needed per case of CIN2+ was 9.5, similar for women below and above 30 years old. The number of colposcopies needed per case of CIN3+ for HPV-16 positivity was 8.5, compared to 17.0 for other categories (P=0.040). Colposcopy efficacy was similar for HPV-18 and HPV-12 other positivity with abnormal cytology.

Conclusion

Taking CIN2+ detection and colposcopy referral rate as endpoints, HPV testing in Singapore can be extended to include women from 25 years old.

A New Brazilian Device for Cervical Cancer Screening: Acceptability and Accuracy of Self-sampling

OBJECTIVE

 To evaluate the accuracy and patient acceptability toward self-sampling using a new device - SelfCervix® - for detecting HPV-DNA.

METHODS

 A total of 73 women aged 25-65 who underwent regular cervical cancer screening from March to October 2016 were included. Women performed self-sampling followed by a physician-sampling, and the samples were analyzed for HPV-DNA. After that, patients were surveyed about their acceptability of self-sampling.

RESULTS

 HPV-DNA detection rate of self-sampling presented high accuracy and was similar to physician-collection. Sixty-four (87.7%) patients answered the acceptability survey. Most patients (89%) considered the self-sampling comfortable, and 82.5% preferred self-sampling to physician-sampling. The reasons cited were time-saving and convenience. Fifty-one (79.7%) reported that they would recommend self-sampling.

CONCLUSION

 Self-sampling using the new Brazilian device SelfCervix® is not inferior in HPV-DNA detection rate compared with physician-collection, and patients are supportive of the method. Therefore, it might be an option to reach under-screened populations in Brazil.

Patient Preferences in Targeted Pharmacotherapy for Cancers: A Systematic Review of Discrete Choice Experiments

BACKGROUND

Targeted pharmacotherapy has been increasingly applied in cancer treatment due to its breakthroughs. However, the unmet needs of cancer patients are still significant, highlighting the urgency to investigate patient preferences. It is unclear how patients deliberate their choices between different aspects of targeted therapy, including cost, efficacy, and adverse events. Since discrete choice experiments (DCEs) have been widely applied to patient preference elicitation, we reviewed DCEs on targeted therapy for different cancers. We also synthesized evidence on the factors influencing patients' choices and their willingness-to-pay (WTP) for survival when treated by targeted therapy.

METHODS

We searched databases, including PubMed, EMBASE and MEDLINE, up to August 16, 2022, supplemented by a reference screening. The attributes from the selected studies were categorized into three groups: outcomes, costs, and process. We also calculated the relative importance of attributes and WTP for survival whenever possible. The purpose, respondents, explanation, findings, significance (PREFS) checklist was used to evaluate the quality of the included DCE studies.

RESULTS

The review identified 34 eligible studies from 13 countries covering 14 cancers, such as breast, ovarian, kidney, prostate, and skin cancers. It also reveals a rising trend of DCEs on this topic, as most studies were published after 2018. We found that patients placed higher weights on the outcome (e.g., overall survival) and cost attributes than on process attributes. On average, patients were willing to pay $561 (95% confidence interval [CI]: $415-$758) and $716 (95% CI $524-$958) out-of-pocket for a 1-month increase in progression-free survival and overall survival, respectively. PREFS scores of the 34 studies ranged from 2 to 4, with a mean of 3.38 (SD: 0.65), suggesting a reasonable quality based on the checklist. However, most studies (n = 32, 94%) did not assess the impact of non-responses on the results.

CONCLUSIONS

This is the first systematic review focusing on patient preferences for targeted cancer therapy. We showcased novel approaches for evidence synthesis of DCE results, especially the attribute relative importance and WTP. The results may inform stakeholders about patient preferences toward targeted therapy and their WTP estimates. More studies with improved study design and quality are warranted to generate more robust evidence to assist decision making.

A systematic review of economic evaluations of cervical cancer screening methods

OBJECTIVE

The aims of this systematic review were to (1) identify primary- and model-based economic evaluations of cervical cancer screening methods and to (2) provide a contextual summary of valuation outcomes associated with three types of cervical cancer screening tests: visual inspection with acetic acid, human papillomavirus deoxyribonucleic acid, and Papanicolaou smear.

INTRODUCTION

Cervical cancer screening is an important public health priority with the potential to improve the detection of precancerous lesions in high-risk females for early intervention and disease prevention. Test performance and cost-effectiveness differ based on the specific screening method used across different platforms. There is a need to appraise existing economic evaluations of cervical cancer screening methods.

METHODS

This review considered primary-based and model-based full economic evaluations of cervical cancer screening methods. The evaluation methods of interest included cost-effectiveness analysis, cost-utility analysis, cost-minimization analysis, cost-benefit analysis, and cost-consequence analysis. We searched Scopus, PubMed, National Health Economic Evaluation Database (NH EED), Cochrane, and the Health Economic Evaluation Database for full economic evaluations of cancer screening methods. No formal date restrictions were applied. Model-based and primary-based full economic evaluations were included. A critical appraisal of included studies was performed by the main investigator, while a second independent reviewer assessed critical appraisal findings for any inconsistencies. Data were extracted using a standardised data extraction tool for economic evaluations. The ultimate outcomes of costs, effectiveness, benefits, and utilities of cervical cancer screening modalities were extracted from included studies, analysed, and summarised.

RESULTS

From a total of 671 screened studies, 44 studies met the study inclusion criteria. Forty-three studies were cost-effectiveness analyses, one study reported both cost-utility and cost-effectiveness outcomes, and another study reported cost utilities of cervical cancer screening methods only. Human papillomavirus (HPV) DNA testing was reported as a dominant stand-alone screening test by 14 studies, while five studies reported visual inspection with acetic acid (VIA) as a dominant stand-alone screening test. Primary HPV screening strategies were dominant in 21 studies, while three studies reported cytology-based screening strategies as the dominant screening method.

CONCLUSIONS

Existing evidence indicates that HPV-based and VIA testing strategies are cost-effective, but this is dependent on setting. Our review suggests the limited cost-effectiveness of cytology-based testing, which may be due in part to the need for specific infrastructures and human resources.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020212454 .

Expression of Chimeric HPV-HIV Protein L1P18 in Pichia pastoris; Purification and Characterization of the Virus-like Particles

Currently, three human papillomavirus (HPV) vaccines are already licensed and all of them are based on virus-like particles (VLPs) of HPV L1 capsid protein but not worldwide accessible. While about 38.0 million people were living with HIV in 2019, only 68% of HIV-infected individuals were accessing antiretroviral therapy as of the end of June 2020 and there is no HIV vaccine yet. Therefore, safe, effective, and affordable vaccines against those two viruses are immediately needed. Both HPV and HIV are sexually transmitted infections and one of the main access routes is the mucosal genital tract. Thus, the development of a combined vaccine that would protect against HPV and HIV infections is a logical effort in the fight against these two major global pathogens. In this study, a recombinant Pichia pastoris producing chimeric HPV-HIV L1P18 protein intracellularly was constructed. After cell disruption, the supernatant was collected, and the VLPs were purified by a combination of ammonium sulfate precipitation, size exclusion chromatography, ultracentrifugation, and ultrafiltration. At the end of purification process, the chimeric VLPs were recovered with 96% purity and 9.23% overall yield, and the morphology of VLPs were confirmed by transmission electron microscopy. This work contributes towards the development of an alternative platform for production of a bivalent vaccine against HPV and HIV in P. pastoris.