Human papillomavirus testing and cervical cytology in primary screening for cervical cancer among women in rural China: comparison of sensitivity, specificity, and frequency of referral

Extended HPV typing test performed better predict value for CIN2+ among elderly women in China

Objective

The aim of this study was to examine the cervical cancer screening practices among women residing in Lingang New District of Shanghai. Moreover, the study aimed to delve into the characteristics of HPV infection and cervical lesions in older women (≥60 years old), seeking for more effective method for cervical cancer screening.

Methods

This is a cross-sectional study enrolled women who were referred to colposcopy and cervical histological examination due to abnormal cytology or HPV tests from Shanghai Sixth People's Hospital between January 2018 and December 2022.

Results

A total of 1,931 women (mean age: 41.8 ± 12.5, range: 18-88 years old) were enrolled, 119 individuals aged ≥ 60 and 1732 aged <60. The infection rates of HPV52, 33, 35, 56, 26 and 81 were significantly higher in the elderly group. Multiple HPV infection rates were also higher in this group and were associated with cervical lesions. The probability of LSIL, HSIL and Ca in women over 60 years old was significantly higher compared to women under 60. The top three HPV genotypes in elderly women with CIN2+ were HPV16, 52, and 58. The Yoden index was higher for extended typing for HPV 31/33/45/52/58(0.41) compared to cytology(0.29), high risk HPV without specific typing(0.07), cotest(cytology and high risk HPV, 0.06 or 0.30), or the current shunt strategy(0.07).

Conclusions

Elderly women still need to continue cervical cancer screening, and extended typing test for HPV16/18/31/33/45/52/58 is a more effective method for this age group.

Testing for viral DNA integration among HPV-positive women to detect cervical precancer: An observational cohort study

OBJECTIVE

Human papillomavirus (HPV) integration is a crucial genetic step in cervical carcinogenesis. This study aimed to evaluate the performance of an HPV integration test for the triage of HPV-positive women.

DESIGN

An observational cohort study.

SETTING

A cervical cancer screening programme in China.

POPULATION

1393 HPV-positive women aged 25-65 years undergoing routine cervical cancer screening and HPV integration testing with 1-year follow-up.

METHODS

The sensitivity, specificity, positive predictive value and negative predictive value between HPV integration and cytology were compared.

MAIN OUTCOME MEASURES

Cervical intraepithelial neoplasia grade 3 or more severe (CIN3+).

RESULTS

Among 1393 HPV-positive patients, 138 (9.9% [8.3-11.5%]) were HPV integration test positive compared with 537 who had abnormal cervical cytology (38.5% [36.0-41.1%]). Compared with cytology, HPV integration exhibited higher specificity (94.5% [93.3-95.8%] versus 63.8% [61.2-66.4%]) and equivalent sensitivity (70.5% [61.4-79.7%] versus 70.5% [61.4-79.7%]) for detection of CIN3+. HPV integration-negative women accounted for 90.1% (1255/1393) of the total population and had a low immediate CIN3+ risk (2.2%). At 1-year follow-up, the progression rate in the HPV integration-positive women was higher than in the HPV integration-negative women (12.0% versus 2.1%, odds ratio 5.6, 95% CI, 2.6-11.9). In 10 conservatively managed integration-negative CIN2 patients, all showed spontaneous regression and seven showed HPV clearance after 1-year follow-up.

CONCLUSION

The HPV integration test may be a precise risk stratification tool for HPV-positive women and could avoid excessive use of invasive biopsies.

The Risk Factors for Cervical Cytological Abnormalities Among Women Infected With Non-16/18 High-Risk Human Papillomavirus: Cross-sectional Study

BACKGROUND

High-risk human papillomavirus (hrHPV) infection is a necessary cause of almost all cervical cancers. Relative to hrHPV 16/18 infection, non-16/18 hrHPV infection is of less concern. However, the increasing prevalence of non-16/18 hrHPV infections has become an important public health issue. The early identification and treatment of cervical cytological abnormalities in women infected with non-16/18 hrHPV reduces the incidence of cervical cancer. To date, no study has examined the risk factors for cytological abnormalities in this high-risk population.

OBJECTIVE

This population-based, cross-sectional study aimed to identify the risk factors for cervical cytological abnormalities in women infected with non-16/18 hrHPV.

METHODS

A total of 314,587 women from the general population were recruited for cervical cancer screening at 136 primary care hospitals in Xiangyang, China. Of these, 311,604 women underwent HPV genotyping, and 17,523 non-16/18 hrHPV-positive women were referred for cytological screening according to the screening program. A logistic regression model was used to assess the risk factors for cytological abnormalities among these non-16/18 hrHPV-positive women. A separate analysis was performed to determine the factors influencing high-grade cytological abnormalities.

RESULTS

The non-16/18 hrHPV infection rate was 5.88% (18,323/311,604), which was 3-fold higher than that of hrHPV 16/18 (6068/311,604, 1.95%). Among the non-16/18 hrHPV-positive women who underwent ThinPrep cytologic test, the overall prevalence rates of cervical cytological abnormalities and high-grade cytological abnormalities were 13.46% (2359/17,523) and 1.18% (206/17,523), respectively. Multivariate logistic regression analysis revealed that women with middle or high school educational attainment were at a higher risk of having cytological abnormalities than those who received primary education (odds ratio [OR] 1.31, 95% CI 1.17-1.45; P<.001, and OR 1.32, 95% CI 1.14-1.53; P<.001, respectively). Living in rural areas (OR 2.58, 95% CI 2.29-2.90; P<.001), gravidity ≥3 (OR 2.77, 95% CI 1.19-6.45; P=.02), cervix abnormalities detected in pelvic examination (OR 1.22, 95% CI 1.11-1.34; P<.001), and having a cervical cancer screening 3 years ago (OR 0.79, 95% CI 0.62-1.00; P=.048) were associated with cytological abnormalities. The risk factors for high-grade cytological abnormalities included middle school education (OR 1.45, 95% CI 1.07-1.98; P=.02), living in rural regions (OR 1.52, 95% CI 1.10-2.10; P=.01), and cervix abnormality (OR 1.72, 95% CI 1.30-2.26; P<.001).

CONCLUSIONS

The dominant epidemic of non-16/18 hrHPV infection is revealed in Chinese women. Multiple risk factors for cervical cytological abnormalities have been identified in women infected with non-16/18 hrHPV. These findings can provide important information for clinically actionable decisions for the screening, early diagnosis, intervention, and prevention of cervical cancer in non-16/18 hrHPV-positive women.

Comparative accuracy of cervical cancer screening strategies in healthy asymptomatic women: a systematic review and network meta-analysis

To compare all available accuracy data on screening strategies for identifying cervical intraepithelial neoplasia grade ≥ 2 in healthy asymptomatic women, we performed a systematic review and network meta-analysis. MEDLINE and EMBASE were searched up to October 2020 for paired-design studies of cytology and testing for high-risk genotypes of human papillomavirus (hrHPV). The methods used included a duplicate assessment of eligibility, double extraction of quantitative data, validity assessment, random-effects network meta-analysis of test accuracy, and GRADE rating. Twenty-seven prospective studies (185,269 subjects) were included. The combination of cytology (atypical squamous cells of undetermined significance or higher grades) and hrHPV testing (excepting genotyping for HPV 16 or 18 [HPV16/18]) with the either-positive criterion (OR rule) was the most sensitive/least specific, whereas the same combination with the both-positive criterion (AND rule) was the most specific/least sensitive. Compared with standalone cytology, non-HPV16/18 hrHPV assays were more sensitive/less specific. Two algorithms proposed for primary cytological testing or primary hrHPV testing were ranked in the middle as more sensitive/less specific than standalone cytology and the AND rule combinations but more specific/less sensitive than standalone hrHPV testing and the OR rule combination. Further research is needed to assess these results in population-relevant outcomes at the program level.

The Performance of Immunocytochemistry Staining as Triaging Tests for High-Risk HPV-Positive Women: A 24-Month Prospective Study

It is urgent to develop an accurate approach to improve the predictive performance of hrHPV-based screening. The aim is to evaluate the performance of p16/Ki-67 and p16/MCM2 staining to triage high-risk human papillomavirus- (hrHPV-) positive women. Cervical specimens were collected from eligible women and tested for hrHPV genotyping, cytology, p16/Ki-67, and p16/MCM2 staining at baseline. Women were invited to participate in follow-up screening by cytology and hrHPV testing at 24 months. Positive women received colposcopy and biopsies. Histopathological diagnoses were the gold standard. 485 women came back for the follow-up screening. The positive rate of p16/Ki-67 was 20.2% and of p16/MCM2 was 27.2%. The positive rates of p16/Ki-67 ( P < 0.001) and p16/MCM2 (P=0.021) were increased by the severity of histopathology findings. Among hrHPV-positive women, the sensitivity, specificity, PPV, and NPV for p16/Ki-67 were 90.9%, 67.0%, 16.5%, and 99.0%, and for p16/MCM2 were 81.8%, 43.1%, 9.4%, and 97.1%. The sensitivity of cytology for triaging hrHPV-positive women were lower than p16/Ki-67 (P=0.012) and p16/MCM2 (P=0.065). The cocktail staining did not add sensitivity to p16/Ki-67 or p16/MCM2 staining alone (P > 0.05), however, cutting down the specificity of p16/Ki-67 staining alone with statistical significance (67.0% vs. 40.2%, P < 0.001). The risk of CIN2+ within 24 months for hrHPV-positive but triaging negative women at baseline was 0.5 (0.1–2.7), 0.7 (0.1–4.1), and 2.4 (1.1–5.0) for p16/Ki-67, p16/MCM2, and cytology, respectively. As an objective and accurate immunocytochemical staining, the p16/Ki-67 and p16/MCM2 dual staining performed better than cytology to triage positive hrHPV. On condition that high-quality cytology is unavailable, immunocytochemical staining by p16/Ki-67 or p16/MCM2 is an option for triaging hrHPV-positive women. The combination of p16/Ki-67 and p16/MCM2 could not improve the accuracy in detecting CIN2+.

Cytology versus HPV testing for cervical cancer screening in the general population

BACKGROUND

Cervical cancer screening has traditionally been based on cervical cytology. Given the aetiological relationship between human papillomavirus (HPV) infection and cervical carcinogenesis, HPV testing has been proposed as an alternative screening test.

OBJECTIVES

To determine the diagnostic accuracy of HPV testing for detecting histologically confirmed cervical intraepithelial neoplasias (CIN) of grade 2 or worse (CIN 2+), including adenocarcinoma in situ, in women participating in primary cervical cancer screening; and how it compares to the accuracy of cytological testing (liquid-based and conventional) at various thresholds.

SEARCH METHODS

We performed a systematic literature search of articles in MEDLINE and Embase (1992 to November 2015) containing quantitative data and handsearched the reference lists of retrieved articles.

SELECTION CRITERIA

We included comparative test accuracy studies if all women received both HPV testing and cervical cytology followed by verification of the disease status with the reference standard, if positive for at least one screening test. The studies had to include women participating in a cervical cancer screening programme who were not being followed up for previous cytological abnormalities.

DATA COLLECTION AND ANALYSIS

We completed a 2 x 2 table with the number of true positives (TP), false positives (FP), true negatives (TN), and false negatives for each screening test (HPV test and cytology) used in each study. We calculated the absolute and relative sensitivities and the specificities of the tests for the detection of CIN 2+ and CIN 3+ at various thresholds and computed sensitivity (TP/(TP + TN) and specificity (TN/ (TN + FP) for each test separately. Relative sensitivity and specificity of one test compared to another test were defined as sensitivity of test-1 over sensitivity of test-2 and specificity of test-1 over specificity of test-2, respectively. To assess bias in the studies, we used the Quality Assessment of Diagnostic test Accuracy Studies (QUADAS) tool. We used a bivariate random-effects model for computing pooled accuracy estimates. This model takes into account the within- and between-study variability and the intrinsic correlation between sensitivity and specificity.

MAIN RESULTS

We included a total of 40 studies in the review, with more than 140,000 women aged between 20 and 70 years old. Many studies were at low risk of bias. There were a sufficient number of included studies with adequate methodology to perform the following test comparisons: hybrid capture 2 (HC2) (1 pg/mL threshold) versus conventional cytology (CC) (atypical squamous cells of undetermined significance (ASCUS)+ and low-grade squamous intraepithelial lesions (LSIL)+ thresholds) or liquid-based cytology (LBC) (ASCUS+ and LSIL+ thresholds), other high-risk HPV tests versus conventional cytology (ASCUS+ and LSIL+ thresholds) or LBC (ASCUS+ and LSIL+ thresholds). For CIN 2+, pooled sensitivity estimates for HC2, CC and LBC (ASCUS+) were 89.9%, 62.5% and 72.9%, respectively, and pooled specificity estimates were 89.9%, 96.6%, and 90.3%, respectively. The results did not differ by age of women (less than or greater than 30 years old), or in studies with verification bias. Accuracy of HC2 was, however, greater in European countries compared to other countries. The results for the sensitivity of the tests were heterogeneous ranging from 52% to 94% for LBC, and 61% to 100% for HC2. Overall, the quality of the evidence for the sensitivity of the tests was moderate, and high for the specificity.The relative sensitivity of HC2 versus CC for CIN 2+ was 1.52 (95% CI: 1.24 to 1.86) and the relative specificity 0.94 (95% CI: 0.92 to 0.96), and versus LBC for CIN 2+ was 1.18 (95% CI: 1.10 to 1.26) and the relative specificity 0.96 (95% CI: 0.95 to 0.97). The relative sensitivity of HC2 versus CC for CIN 3+ was 1.46 (95% CI: 1.12 to 1.91) and the relative specificity 0.95 (95% CI: 0.93 to 0.97). The relative sensitivity of HC2 versus LBC for CIN 3+ was 1.17 (95% CI: 1.07 to 1.28) and the relative specificity 0.96 (95% CI: 0.95 to 0.97).

AUTHORS' CONCLUSIONS

Whilst HPV tests are less likely to miss cases of CIN 2+ and CIN 3+, these tests do lead to more unnecessary referrals. However, a negative HPV test is more reassuring than a negative cytological test, as the cytological test has a greater chance of being falsely negative, which could lead to delays in receiving the appropriate treatment. Evidence from prospective longitudinal studies is needed to establish the relative clinical implications of these tests.

Pooled analysis on the necessity of random 4-quadrant cervical biopsies and endocervical curettage in women with positive screening but negative colposcopy

Controversy remains over whether random cervical biopsies and endocervical curettage (ECC) should be used in women with positive screening but negative colposcopy. Our paper aims to determine the indications for random biopsies and ECC among these screened positive women.Three thousand two hundred thirteen women with any positive screening test result but negative colposcopy, who received random 4-quadrant biopsies, were pooled from 17 population-based cervical cancer screening studies done in China from 1999 to 2008. The detection rates of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and CIN grade 3 or worse (CIN3+) stratified by cytology and high-risk human papillomavirus (HR-HPV) status were assessed, as well as the false negative rates for CIN2+ and CIN3+ by random biopsies without ECC.Compared with women with negative cytology and positive HR-HPV, those with atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion (ASC-US/LSIL) and negative HR-HPV had the equivalent lower risks of CIN2+ and CIN3+, but ascending risks were observed in the groups of ASC-US/LSIL and positive HR-HPV, and atypical glandular cells/atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion/high-grade squamous intraepithelial lesion or worse (AGC/ASC-H/HSIL+). If random biopsies were only taken without ECC, 9.3% of CIN2+ and 18.5% of CIN3+ would have been missed.For women with any positive screening but negative colposcopy, in areas with good cytological infrastructure, it was necessary to perform random biopsies plus ECC on those with cytological ASC-US/LSIL and positive HR-HPV, AGC, ASC-H, or HSIL+. In contrast, those with other results should be followed up.

Risk factors for cervical intraepithelial neoplasia and cervical cancer in Chinese women: large study in Jiexiu, Shanxi Province, China

We aimed to investigate the risk factors for cervical intraepithelial neoplasia (CIN) in Jiexiu, Shanxi Province, China. Twenty thousand eligible married women (age: 18-65 years) were administered with a questionnaire on potential risk factors for CIN and underwent liquid based Pap test. All women with abnormal cytological results underwent colposcopy with biopsy. Based on the biopsy pathology results, women were then assigned to either study group (with CIN) or control group (negative for histological results and volunteered to participate in the follow up study). The women in both study group and control group underwent vaginal microflora detection and dietary survey. The potential risk factors were analyzed by using ordinal logistic regression. Among the 20,000 women ne 1,438 women (7.19%) had cytologic abnormalities and 410 (2.05%) women were diagnosed histologically with CIN lesions, including 317 (1.58%) with CIN1, 93 (0.50%) with CIN2/3and 11 (55/100,000) with squamous cell carcinoma (SCC). The average daily dietary folate intake was significantly lower in the study group (344.61±153.07μg) than in the control group (371.50±166.58μg; P<0.001). Multivariate analysis demonstrated that age of 56-65 years, farming as the husband's occupation, unwashing the vulva after sexual intercourse, and low self-reported folate intake were positively associated with CIN development and might have contribution to the increased CIN incidence in this population. These findings may provide help to develop the strategies to reduce the risk of cervical cancer in China.

Evaluation of several screening approaches for detection of cervical lesions in rural Shandong, China

PURPOSE

The study was designed to: (1) investigate the prevalence of high-risk human papillomavirus (HR- HPV) infection and cervical neoplasia; and (2) evaluate clinical performance of visual inspection with acetic acid/ Lugol's iodine (VIA /VILI), Pap smear, high-risk human papillomavirus (HR-HPV) DNA test for detecting cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and (3) explore appropriate screening approach in rural areas of Shandong Province.

MATERIALS AND METHODS

A total of 3,763 eligible women from Yiyuan County in Yimeng mountainous areas of rural Shandong, China, were enrolled and underwent Pap smear, HR-HPV DNA testing by Hybrid Capture 2 (HC2), and VIA /VILI tests. Women positive in any test were referred to colposcopy and biopsy as indicated.

RESULTS

The prevalence of HR-HPV infection among all enrolled women was 11.1% and that in healthy women was 9.9%. In total 33 cases of CIN1, 16 cases of CIN2, 6 cases of CIN3 but none of cervical cancer were detected and the crude prevalence of CIN2+ was 0.58%. For detecting CIN2+, the sensitivity of HR-HPV DNA testing, VIA/VILI, Pap smear was 90.9%, 77.3%, 81.8%, respectively. Pap smear had the best specificity of 98.2%, followed by HR-HPV DNA testing with specificity of 89.4%, VIA/VILI had the lowest specificity of 81.2%. Colposcopy referral rate of HR-HPV DNA testing, VIA/VILI, Pap smear was 11.1%, 18.5%, 2.3%, respectively.

CONCLUSIONS

Our results suggest that HR-HPV DNA testing alone might be appropriate for primary cervical cancer screening in rural low-resource areas of Shandong Province, China.

Managing the changing burden of cancer in Asia

Asia accounts for 60% of the world population and half the global burden of cancer. The incidence of cancer cases is estimated to increase from 6.1 million in 2008 to 10.6 million in 2030, due to ageing and growing populations, lifestyle and socioeconomic changes. Striking variations in ethnicity, sociocultural practices, human development index, habits and dietary patterns are reflected in the burden and pattern of cancer in different regions. The existing and emerging cancer patterns and burden in different regions of Asia call for political recognition of cancer as an important public health problem and for balanced investments in public and professional awareness. Prevention as well as early detection of cancers leads to both better health outcomes and considerable savings in treatment costs. Cancer health services are still evolving, and require substantial investment to ensure equitable access to cancer care for all sections of the population. In this review, we discuss the changing burden of cancer in Asia, along with appropriate management strategies. Strategies should promote healthy ageing via healthy lifestyles, tobacco and alcohol control measures, hepatitis B virus (HBV) and human papillomavirus (HPV) vaccination, cancer screening services, and vertical investments in strengthening cancer healthcare infrastructure to improve equitable access to services.

Lower cost strategies for triage of human papillomavirus DNA-positive women

Using human papillomavirus (HPV) testing for cervical cancer screening in lower-resource settings (LRS) will result in a significant number of screen-positive women. This analysis compares different triage strategies for detecting cervical precancer and cancer among HPV-positive women in LRS. This was a population-based study of women aged 25-65 years living in China (n = 7,541). Each woman provided a self-collected and two clinician-collected specimens. The self-collected and one clinician-collected specimen were tested by two HPV DNA tests-careHPV™ and Hybrid Capture 2; the other clinician-collected specimen was tested for HPV16/18/45 E6 protein. CareHPV™-positive specimens were tested for HPV16/18/45 DNA. HPV DNA-positive women underwent visual inspection with acetic acid (VIA) and then colposcopic evaluation with biopsies. The performance for detection of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) among HPV DNA-positive women was assessed for different triage strategies: HPV16/18/45 E6 or DNA detection, VIA, colposcopic impression, or higher signal strength (≥10 relative light units/positive control [rlu/pc]). The percent triage positive ranges were 14.8-17.4% for VIA, 17.8-20.9% for an abnormal colposcopic impression; 7.9-10.5% for HPV16/18/45 E6; 23.4-28.4% for HPV16/18/45 DNA; and 48.0-62.6% for higher signal strength (≥10 rlu/pc), depending on the HPV test/specimen combination. The positivity for all triage tests increased with severity of diagnosis. HPV16/18/45 DNA detection was approximately 70% sensitive and had positive predictive values (PPV) of approximately 25% for CIN3+. HPV16/18/45 E6 detection was approximately 50% sensitive with a PPV of nearly 50% for CIN3+. Different triage strategies for HPV DNA-positive women provide important tradeoffs in colposcopy or treatment referral percentages and sensitivity for prevalent CIN3+.

Combined screening of cervical cancer, breast cancer and reproductive tract infections in rural China

OBJECTIVES

To investigate the current prevalence and knowledge of cervical cancer, breast cancer and reproductive tract infections (RTIs) in rural Chinese women, and to explore the acceptance and feasibility of implementing a combined screening program in rural China.

METHODS

A population-based, cross-sectional study was conducted among women aged 30 to 59 years old in Xiangyuan County, Shanxi Province from 2009 to 2010. Socio-demographic characteristics, knowledge of cervical cancer, breast cancer and RTIs, and the attitude toward single or combined screening were collected by an interview questionnaire. Each participant received a clinical examination of the cervix, breast and reproductive tract. Examinations included visual inspection, mammography, laboratory tests and pathological diagnosis.

RESULTS

A total of 1,530 women were enrolled in this study. The prevalence of cervical precancerous lesions, suspicious breast cancer, suspicious benign breast disease and RTIs was 1.4%, 0.2%, 14.0% and 54.3%, respectively. Cervicitis, trichomonas vaginitis, and bacterial vaginitis were the three most common RTIs among our participants. Television, radio broadcast, and public education during screening were the major source of healthcare knowledge in rural China. Moreover 99.7% of women expressed great interest in participating in a combined screening project. The affordable limit for combined screening project was only 50 RMB for more than half of the rural women.

CONCLUSION

A combined screening program would be more effective and popular than single disease screening projects, while appropriate accompanied education and a co-pay model for its successful implementation need to be explored, especially in low-resource settings.

Estimation of the costs of cervical cancer screening, diagnosis and treatment in rural Shanxi Province, China: a micro-costing study

Background

Cost estimation is a central feature of health economic analyses. The aim of this study was to use a micro-costing approach and a societal perspective to estimate aggregated costs associated with cervical cancer screening, diagnosis and treatment in rural China.

Methods

We assumed that future screening programs will be organized at a county level (population ~250,000), and related treatments will be performed at county or prefecture hospitals; therefore, this study was conducted in a county and a prefecture hospital in Shanxi during 2008–9. Direct medical costs were estimated by gathering information on quantities and prices of drugs, supplies, equipment and labour. Direct non-medical costs were estimated via structured patient interviews and expert opinion.

Results

Under the base case assumption of a high-volume screening initiative (11,475 women screened annually per county), the aggregated direct medical costs of visual inspection, self-sampled careHPV (Qiagen USA) screening, clinician-sampled careHPV, colposcopy and biopsy were estimated as US$2.64,$7.49,$7.95,$3.90 and $5.76, respectively. Screening costs were robust to screening volume (<5% variation if 2,000 women screened annually), but costs of colposcopy/biopsy tripled at the lower volume. Direct medical costs of Loop Excision, Cold-Knife Conization and Simple and Radical Hysterectomy varied from $61–544, depending on the procedure and whether conducted at county or prefecture level. Direct non-medical expenditure varied from $0.68–$3.09 for screening/diagnosis and $83–$494 for pre-cancer/cancer treatment.

Conclusions

Diagnostic costs were comparable to screening costs for high-volume screening but were greatly increased in lower-volume situations, which is a key consideration for the scale-up phase of new programs. The study’s findings will facilitate cost-effectiveness evaluation and budget planning for cervical cancer prevention initiatives in China.

Estimation of the costs of cervical cancer screening, diagnosis and treatment in rural Shanxi Province, China: a micro-costing study

BACKGROUND

Cost estimation is a central feature of health economic analyses. The aim of this study was to use a micro-costing approach and a societal perspective to estimate aggregated costs associated with cervical cancer screening, diagnosis and treatment in rural China.

METHODS

We assumed that future screening programs will be organized at a county level (population ~250,000), and related treatments will be performed at county or prefecture hospitals; therefore, this study was conducted in a county and a prefecture hospital in Shanxi during 2008-9. Direct medical costs were estimated by gathering information on quantities and prices of drugs, supplies, equipment and labour. Direct non-medical costs were estimated via structured patient interviews and expert opinion.

RESULTS

Under the base case assumption of a high-volume screening initiative (11,475 women screened annually per county), the aggregated direct medical costs of visual inspection, self-sampled careHPV (Qiagen USA) screening, clinician-sampled careHPV, colposcopy and biopsy were estimated as US$2.64,$7.49,$7.95,$3.90 and $5.76, respectively. Screening costs were robust to screening volume (<5% variation if 2,000 women screened annually), but costs of colposcopy/biopsy tripled at the lower volume. Direct medical costs of Loop Excision, Cold-Knife Conization and Simple and Radical Hysterectomy varied from $61-544, depending on the procedure and whether conducted at county or prefecture level. Direct non-medical expenditure varied from $0.68-$3.09 for screening/diagnosis and $83-$494 for pre-cancer/cancer treatment.

CONCLUSIONS

Diagnostic costs were comparable to screening costs for high-volume screening but were greatly increased in lower-volume situations, which is a key consideration for the scale-up phase of new programs. The study's findings will facilitate cost-effectiveness evaluation and budget planning for cervical cancer prevention initiatives in China.

Comparison of ThinPrep and SurePath liquid-based cytology and subsequent human papillomavirus DNA testing in China

BACKGROUND

Liquid-based cytology (LBC) has been compared with conventional cytology in numerous studies. In the current study of 2 LBC systems, the accuracy, rates of unsatisfactory cytology, and sufficiency of residual LBC specimens for Hybrid Capture 2 (HC2) HPV DNA testing were compared.

METHODS

Eligible women ages 30 to 49 years were recruited for this cross-sectional population-based study in rural China. Women were assessed by visual inspection with acetic acid (VIA), LBC, and high-risk HPV HC2 DNA assay. Cervical specimens were preserved according to SurePath or ThinPrep protocols. LBC results were manually read. HC2 testing was performed on specimens with sufficient residual volume. Colposcopies and biopsies were performed on women who were VIA positive at the time of initial screening. Women with abnormal LBC or HC2 test results were called back for colposcopies and 4-quadrant cervical biopsies.

RESULTS

Of 2005 eligible women, 972 were tested by SurePath and 1033 by ThinPrep. Compared with SurePath samples, ThinPrep samples had higher rates of unsatisfactory cytology (0.2% for SurePath and 1.5% for ThinPrep) and insufficient residual volume for HC2 (0.0% for SurePath and 18.2% for ThinPrep). SurePath samples yielded higher sensitivities and similar specificities for LBC and HC2 testing of residual specimens, but these differences were not determined to be significant by area-under-the-curve analysis (LBC performance: 0.89 for SurePath and 0.85 for ThinPrep; HC2 performance: 0.91 for SurePath and 0.89 for ThinPrep).

CONCLUSIONS

Both methods yielded similar validity in detecting significant cervical lesions. However, SurePath samples yielded higher rates of satisfactory LBC slides and sufficient residual volume for HC2.

The burden of cervical cancer in China: synthesis of the evidence

The burden of cervical cancer in China has not been characterized in detail. We reviewed cervical cancer data from national mortality surveys and registries, and conducted a meta-analysis to estimate the prevalence of high-grade lesions (HSIL) and high-risk human papillomavirus (HR-HPV) infections in rural Shanxi Province. We found that a national survey in the 1970s estimated age-standardized cervical cancer mortality rates as ~15 and ~83/100,000 women nationally and in Xiangyuan, Shanxi; but the latest survey (2004-2005) found much lower rates of ~3 and ~7/100,000, respectively. IARC registries record age-standardized cervical cancer incidence in China as <5/100,000 (1998-2002); but the five registry sites cover <2% of the population, and the gross domestic product per capita at each of the registry sites is higher than China's average (by a factor ranging from 1.3 to 3.9). The pooled estimate of the prevalence of HSIL and HR-HPV in women aged 30-54 years in Shanxi was 3.7%(95%CI:2.7-4.8%) and 17.2%(95%CI:13.1-21.3%), respectively. Based on a feasible range informed by the incidence data for China and other unscreened populations, the predicted indicative annual number of new cervical cancer cases nationally, in the absence of any intervention, ranges from ~27,000 to 130,000 (2010) to 42,000 to 187,000 (2050). In conclusion, recent data suggest comparatively low rates of cervical cancer incidence in China, which may be partly explained by the location of registry sites in higher socioeconomic status areas. However, the evidence is consistent with considerable heterogeneity within China, with a higher disease burden in some rural areas such as Shanxi. Therefore, the lower reported rates of cervical cancer in China should be interpreted cautiously.

Human papillomavirus testing in primary cervical screening and the cut-off level for hybrid capture 2 tests: systematic review

OBJECTIVE

To determine the trade-off between the sensitivity and the specificity for high grade cervical intraepithelial neoplasia at hybrid capture 2 cut-off values above the standard ≥ 1 relative light units/cut-off level (rlu/co).

DESIGN

Systematic review.

DATA SOURCES

PubMed.

STUDY SELECTION

Randomised controlled trials in primary cervical screening using hybrid capture 2 testing in the intervention arms. Articles published until August 2010 were included if the numbers of women with positive test results and with cervical intraepithelial neoplasia were stratified by hybrid capture 2 cut-off levels.

PARTICIPANTS

Women in the baseline screening rounds of the trials.

INTERVENTIONS

Hybrid capture 2 screening in the baseline round including the diagnostic follow-up as practised in the randomised controlled trials and as reported by hybrid capture 2 cut-off values.

RESULTS

Owing to heterogeneity in the trials, meta-analysis was not possible. Including cut-off values up to ≥ 10 rlu/co, 25 observation points were available for analysis. The relative sensitivity for cervical intraepithelial neoplasia grade III or higher at cut-off levels of ≥ 2, ≥ 4 or ≥ 5, and ≥ 10 rlu/co compared with a cut-off level of ≥ 1 rlu/co varied by trial, but at their lowest they were 0.97, 0.92, and 0.91, respectively. A similar pattern was observed for cervical intraepithelial neoplasia grade II or higher. The specificity would increase by at least 1%, 2%, and 3%, respectively, so that up to 24%, 39%, and 53%, of positive hybrid capture 2 test results not associated with high grade neoplasia could be avoided. Only two outliers existed to this general pattern.

CONCLUSIONS

Although the data were derived from the baseline screening rounds only, the decrease in the sensitivity for high grade cervical intraepithelial neoplasia using a hybrid capture 2 cut-off level between ≥ 2 rlu/co and ≥ 10 rlu/co seemed acceptable given the international recommendations for testing for human papillomavirus DNA in cervical screening, which require 90% or more sensitivity for cervical intraepithelial neoplasia grade II or higher compared with hybrid capture 2 at ≥ 1 rlu/co. The data suggest that the hybrid capture 2 cut-off level could be increased in primary screening; this seems reasonably safe and is significantly less burdensome for women.

Performance of high-risk human papillomavirus DNA testing as a primary screen for cervical cancer: a pooled analysis of individual patient data from 17 population-based studies from China

BACKGROUND

Controversy remains over whether high-risk human papillomavirus (HPV) DNA testing should be used as a primary screen for cervical cancer. The aims of our study were to assess whether HPV DNA testing could be applied to cervical-cancer screening programmes in China, as well as other similar developing countries.

METHODS

We did a pooled analysis of population-based cervical cancer screening studies done in mainland China from 1999 to 2008 with concurrent HPV DNA testing (Hybrid Capture 2 assay; Qiagen, Gaithersburg, MD, USA), liquid-based cytology (LBC), and visual inspection with acetic acid (VIA). Eligible women were sexually active, not pregnant, had an intact uterus, and had no history of cervical intraepithelial neoplasia (CIN), cervical cancer, or pelvic irradiation. All women positive for any test were referred for colposcopy and biopsy. Cervical lesions were diagnosed by directed or random biopsy. We assessed the diagnostic accuracy of HPV DNA testing for the detection of CIN grade 3 or greater.

FINDINGS

30,371 women from 17 cross-sectional, population-based studies in various parts of China were screened. 1523 women were subsequently excluded because of inadequate HPV DNA specimens or they did not have a biopsy taken, which included women with atypical squamous cells of undetermined significance; low-grade squamous intraepithelial lesion or worse; positive HPV, negative cytology, and missing or positive colposcopy results; and unsatisfactory cytology results. HPV DNA testing had a higher sensitivity of 97·5% (95% CI 95·7-98·7) for detection of CIN grade 3 or worse, and a lower specificity of 85·1% (82·3-87·9), compared with cytology (sensitivity 87·9% [95% CI 84·7-90·7], specificity 94·7% [93·5-96·0]) and VIA (54·6% [48·0-61·2], 89·9% [86·8-93·0]). Sensitivity did not vary by study or age (<35 years, 35-49 years, ≥50 years); however, specificity did vary with age (p<0·0001) and was highest in women younger than 35 years (89·4%; 95% CI 86·1-91·5). An increase in the positive cutoff point from the manufacturer recommended 1 pg/mL to 2 pg/mL led to a decrease in the overall HPV DNA positivity from 16·3% to 13·9% (p<0·0001), which could result in a decrease in referral rates, although sensitivity was slightly lower (97·5% to 95·2%). An increase in the cutoff point to 10 pg/mL in women younger than 35 years maintained a high sensitivity 97·7% (95% CI 87·7-99·9) and increased specificity to 93·5% (95% CI 91·9-94·6).

INTERPRETATION

HPV DNA testing is highly sensitive and moderately specific for CIN grade 3 or worse, with consistent results across study sites and age groups-including women younger than 35 years. A rise in the cutoff point might be beneficial for future screening programmes in China, especially when screening women younger than 35 years.