Effectiveness of High-risk Human Papillomavirus Testing for Cervical Cancer Screening in China

Key Points Question Does integration of high-risk human papillomavirus (hrHPV) testing into China’s national screening program lead to better outcomes than current primary screening approaches? Findings In this randomized clinical trial that included 60 732 women, hrHPV testing as primary screening provided a 2.0-fold to 2.7-fold yield for cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse compared with cytology or visual inspection with acetic acid and Lugol iodine at baseline. It also resulted in a significantly lower risk of cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse for baseline-negative women under routine conditions in primary health care settings in rural areas across China. Meaning It is reasonable to incorporate hrHPV testing (polymerase chain reaction–based testing for urban areas, hybrid capture–based testing for rural areas) as a primary screening method into China’s current national screening program.

primary screening is based on the data of HC2, which was approved by America FDA for cervical cancer screening in 2003. However, it is difficult to be implemented in low-resource settings because of the price, and requirement of experienced laboratory and high-quality lab conditions. It is imperative for Chinese scientists to explore and find an affordable, fast, simple test that could be Foundation. This project will obtain the nationwide data of HPV testing as primary screening, and evaluate the feasibility and effectiveness of HPV testing in large-scale population-based cervical cancer screening in China.
There may be several options for primary screening of cervical cancer in future, according to the characteristics of the population, economic status, and the health resources. High-quality researches of cervical cancer screening and pilot studies have been conducted in China. However, the protocol of the national screening program needs to be updated. It is important to evaluate the performance of the current screening, optimizing the strategies, investigating the capacity of health service system in primary care settings, conducting health economics evaluation, and developing project management standards for large population.

Overall
This project aims to explore and determine the most efficient, cost-effective, and well acceptable screening program that appropriate for different economic level areas in China, optimizing the screening strategies that can be implemented nationwide.

Specific objectives
2.2.1 To explore and evaluate the short-term clinical performance of primary screening methods in real-world. Compare the accuracy, efficiency and missed diagnosis rate of the three approaches. Evaluate the performance of the different screening strategies under the basic conditions of different economic levels in China.
2.2.2 To evaluate the economic efficiency for screening arms in population-based screening, analysis the medium-and long-term effect, cost-effectiveness and costbenefit. Explore the appropriate strategies for cervical cancer screening in China.
The decision analysis model of health economics will be established to explore the feasibility of incorporating cervical cancer screening and early diagnosis into the national budget.

2.2.3
To evaluate the awareness and attitude of cervical cancer screening in different population, and investigate the potential barriers. It can provide evidence for the promotion, education and mobilization of cervical cancer screening. It can also identify potential obstacles of participation of the target women, problems faced by health workers and police makers at all levels, and provide evidences for the government.
2.2.4 Cancer monitoring system will be established to monitor the risk factors, morbidity and mortality of cervical cancer, and observe dynamically. Training program will be provided to the local cancer registry staff, improving the quality of cancer registration.

Proposal
3.1 Project contents and key issues to be resolved

Clinical research
In the first year, enrolled women would be screened by cytology, VIA/VILI (only for rural sites) or HPV testing, respectively. In the third year, enrolled women would be screened by cytology, HPV testing or VIA/VILI (only for rural sites) simultaneously. Women with positive primary screening result would be refer to triage or colposcopy (Figure1a, 1b). The pathological results are the gold standards to determine whether treatment is needed.

Economic evaluation
Including establish models, field investigation and data collection. Based on the previous data from the department of Epidemiology in CHCAMS, the models would be established and adjusted. Collect the data from cancer registration, and incorporate the relevant parameters into the models to simulate the occurrence and development of cervical cancer, and to predict the medium-and long-term screening effect and costs.
3.1.3 Evaluate and compare the awareness and attitude of cervical cancer screening among different population, including the local government staff and local health workers from the counties, towns and villages.
3.1.4 Investigate the risk factors, monitor the morbidity and mortality of cervical cancer, and observe the changes. Improve the quality of cancer registration, and obtain the data of cervical cancer in local sites.
Key issues to be resolved in this study: 1. Under the conditions of primary facilities and technicians, which screening strategy is the most feasible and efficient?
2. How to get the most profit with the limited resource input? Can China's current public health system support high quality cervical cancer screening in areas with insufficient health resources and carry out it sustainably?
3. How to get more women to volunteer for screening programs? How to solve the difficulties faced by health workers and government managers? How to improve the quality of screening programs from the perspective of managers? 4. Can the existing cancer registration system effectively evaluate the mediumand long-term effects of screening programs? What are the risk factors for rural women? Has it changed and what is the trend of change?

Design
It is a multi-center population-based screening cohort study. Multi-stage sampling would be conducted.

Population
This study is embedded in the national cervical screening program of China. The inclusion criteria as follows: ○ 1 35-64 years-old; ○ 2 No history of cervical cancer or hysterectomy;○ 3 Non-pregnancy, without pregnant symptoms; ○ 4 Understand the study procedures and voluntarily participated.

Sample size
○ 1 Primary out come Positive rate of primary screening and CIN2+ detection rate.

○ 2 Hypothesis
The detection rates of HPV are statistically different from that of existing screening methods in real-world.

○ 3 Calculation
The detection rate of CIN2+ in the previous reported data of the national cancer screening program was 0.14%. Pilot study showed that the detection rate of CIN2+ of HPV was 0.55%. Considering that national cancer screening sites are experienced with VIA/VILI or cytology, we assume that the detection rate of CIN2+ for VIA/VILI and cytology to be 0.19%. The adjusted α level of the multiple tests was 0.025 in rural sites, the minimum sample size for each arm is 7055 providing a power of 90% to detect the difference. We assume the follow-up rate of the screened population is 80% and the sample size for each arm is 8,819.
The α level was 0.05 in urban sites, the minimum sample size for each arm is 5,973 that providing a power of 90%. We assume the follow-up rate of the screened population is 80% and the sample size for each arm is 7,467. The sample size of 63,000 in the preliminary application plan can meet the expected analysis requirements.

Sampling
Based on 221 national cervical cancer screening sites, multi-stage sampling would be conducted (Three-stage sampling) as follows.
○ 1 According to geographical location, the 221 national screening sites are divided into 7 regions (northeast, north, northwest, central, east, south, and southwest).
○ 2 According to the data of the national cancer registration and the local incidence of cervical cancer, 2-4 sites would be selected by purposive sampling from each geographical region, including high risk areas (>20/10 5 ), medium risk areas (10-20/10 5 ) and low risk areas (<10/10 5 ).
○ 3 3000 eligible women would be recruited by convenient sampling from each selected screening site.

Clinical research methods
The 3000 women from each site would be randomly assigned into three arms by software. The randomization program, generated by statisticians at the CHCAMS, is pre-embedded and hidden in an ACCESS registration database sent to each project site. In the first-round screening, enrolled women would be screened by HPV testing, cytology or VIA/VILI (only for rural sites). In the third year, enrolled women would be screened by HPV testing, cytology or VIA/VILI (only for rural sites) simultaneously (Figure1a,1b). All the clinical examination, sample collection and laboratory testing would be performed by local health workers.

○ 1 Cytology
It has been proven that cytology-based screening has proved to be an effective screening method for cervical cancer in developed countries, and it is also one of the optional methods in the national screening in China. All slides would be graded by a local pathologist according to Bethesda 2001 classification system, atypical squamous cells of undetermined significance (ASC-US) or worse lesion are defined as abnormal cytology.
○ 2 VIA/VILI In developing countries, it has been proved that VIA/VILI is an effective method for primary screening, and it is also recommended as primary screening in the national program. All the clinical examination would be performed by local health workers in our program. The gynecologist will examine the cervix with naked eyes under a bright halogen focus lamp after applying 5% acetic acid for VIA/VILI, and the result would be recorded 1 minute later. Lugol`s iodine should be applied if necessary. Any abnormal of VIA or VILI would be referred to colposcopy.

○ 3 HPV testing
The HPV test selected should have been approved by the CFDA. careHPV test has been shown in several studies to be optimal in low resource areas, and would be used in rural sites in this program. Roche cobas 4800 or Zhijiang HPV genotyping would be used as primary screening in urban sites. Women with positive results would be referred. All the clinical sample collection would be performed by local gynecologists. All laboratory work would be conducted by trained local lab technician.

○ 4 Colposcopy
Women will be recalled for colposcopy according to the primary screening or referral results. Lesion-targeted biopsies were performed. In cases of high-grade cytology abnormality but negative colposcopy findings, four-quadrant random biopsy at the squamous column junction and endocervical curettage (ECC) was performed.

○ 5 Pathological diagnosis
The histopathology is the gold standard for the treatment or follow-up. Women with negative diagnosis or CIN1 would be followed-up in the second-round screening. Women with CIN2+ diagnosis will leave the program and should be treated in time. The diagnosis of the local pathologists will be reviewed be a pathologist from the supervise hospital.

Economic evaluation
Including establish models, field investigation and data collection. Based on the previous data from the department of epidemiology in CHCAMS, establish and adjust economic evaluation models by TreeAge Pro software. Collect the data of screening and treatment, and cost for different population by fields investigation, as well as cancer registry data. The parameters will be incorporated into the model to simulate the occurrence and development of cervical cancer of the three arms, and predicting the medium and long-term screening effect and the costs.
By estimating the incidence, mortality, and the cumulative effects such as lifetime risk of cervical cancer, and lifesaving costs and incremental cost, under the guidance of the current national screening program, including the age range and interval, evaluating the best strategy, thus providing evidence for nationwide cervical cancer.

Cognitive survey
To investigate the cognition of the screening population on cervical cancer screening, and to compare the attitude on different screening methods of the screened population. Besides, we will investigate the cognition and attitude of the local government of county, township and villages, and the local medical workers.
To investigate the reproductive status of women China, to evaluated the cognition and attitude of screened population and the organizer, to recognize the potential obstacles of large-scale population screening, and to find the solutions, so as to provide evidences for police makers.

Risk factors monitoring of, morbidity and mortality of cervical cancer registry
The population risk factors in the selected screening sites will be monitored by investigator. A questionnaire is designed for investigating the risk factors of cervical cancer. Trained doctors will followed-up the screened population to investigate the exposure to environmental risk factors. The project plans to further improve the cancer registration system at the study site, so as to obtain a complete and accurate information of the incidence and mortality of cervical cancer.

Data management
Visual FoxPro will be used for data management. All data will be double-input in the database by separated trained investigators and double-checked. SPSS, SAS or other statistical software were used to analyze qualitative and quantitative indicators. The Markov model was established by using TreeAge software to simulate the natural history and history of cervical cancer and calculate the economic evaluation indexes such as QALYs and DALYs. All statistical tests were double-sided at the 0.05 level.

Evaluation indicators and methods
The clinical data and survey data obtained from the study sites will be used to evaluate the efficiency of the screening, the health economics indicators, and the cognition and attitude status. Detailed calculation indicators and analysis methods are as follows: ○ 1 Analysis of the clinical screening data Indicators: positive rate of the three primary screening methods, CIN2+ detection rate, positive predictive value and early diagnosis rate; false negative rate and negative predictive value. The incidence and mortality of cervical cancer in the areas during the program will be tracked using the average of cancer registration data in the 2 years prior to the program as the baseline.
Positive rate: the proportion of women, who need to be referred for colposcopy according to the definition of the study. Statistical analysis methods: chi-square test was used for comparison of categorical data, and LSD, Bonferroni and other methods were used for multiple comparisons.
Quantitative data will be analyzed by t test, variance analysis and so on.

○ 3 Analysis of cognition and attitude survey data
The knowledge, feelings and attitude towards cervical cancer screening (stratified by age, education level, occupation, etc.) will be compared. To investigate the awareness of cervical cancer screening among health workers (maternal and child care system and other primary health care system) and government policymakers (department of science, education, and health, or other government departments.
Statistical analysis methods: chi-square test was used for comparison of categorical data, and LSD, Bonferroni and other methods were used for multiple comparisons.
Quantitative data will be analyzed by t test, variance analysis and so on.

Informed consent and ethical issues
Approval from the ethics committee of Peking union medical college hospital, Chinese academy of medical sciences will be obtained before the enrolment, and all participating hospitals should approve the study as well. All enrolled women will be screened with one of the primary screening approaches free of charge.
Women will be adequately informed of the benefits and harms of participating in the study, completely voluntary, and they could drop out of the study at any time.
Women could only participate in the study after signing the informed consent.

Quality control
The current established site from the national screening program will be selected as the study sites. With experiences of field work, primary screening sites carry out screening work under the guidance of superior hospital. The followings are details of quality control: ○ 1 Before launch of the study, the research team shall formulate and finalize working plan, operation manual, questionnaire and other management documents.

Figure 1b. Flowchart of Clinical Study in Rural Sites
a. Areas without cytological ability are randomly divided into HPV testing or VIA/VILI arm by 2:1 ratio; b. Areas without cytological capacity are randomly divided into VIA/VILI-triage or direct colposcopy by 1:1 ratio.

Medical workers Government officials
To analyze the knowledge and attitudes for cervical screening among rural women.
To analyze the knowledge and attitudes for cervical screening among officials.
To analyze the knowledge and attitudes for cervical screening among medical workers.