Use of an expanded gold standard to estimate the accuracy of colposcopy and visual inspection with acetic acid

Colposcopy Accuracy and Diagnostic Performance: A Quality Control and Quality Assurance Survey in Italian Tertiary-Level Teaching and Academic Institutions-The Italian Society of Colposcopy and Cervico-Vaginal Pathology (SICPCV)

Quality Control (QC) and Quality Assurance (QA) principles are essential for effective cervical cancer prevention. Being a crucial diagnostic step, colposcopy's sensitivity and specificity improvements are strongly advocated worldwide since inter- and intra-observer differences are the main limiting factors. The objective of the present study was the evaluation of colposcopy accuracy through the results of a QC/QA assessment from a survey in Italian tertiary-level academic and teaching hospitals. A web-based, user-friendly platform based on 100 colposcopic digital images was forwarded to colposcopists with different levels of experience. Seventy-three participants were asked to identify colposcopic patterns, provide personal impressions, and indicate the correct clinical practice. The data were correlated with a panel of experts' evaluation and with the clinical/pathological data of the cases. Overall sensitivity and specificity with the threshold of CIN2+ accounted for 73.7% and 87.7%, respectively, with minor differences between senior and junior candidates. Identification and interpretation of colposcopic patterns showed full agreement with the experts' panel, ranging from 50% to 82%, in some instances with better results from junior colposcopists. Colposcopic impressions correlated with a 20% underestimation of CIN2+ lesions, with no differences linked to level of experience. Our results demonstrate the good diagnostic performance of colposcopy and the need for improving accuracy through QC assessments and adhesion to standard requirements and recommendations.

Performance of screening tools for cervical neoplasia among women in low- and middle-income countries: A systematic review and meta-analysis

OBJECTIVE

To evaluate the performance of visual inspection with acetic acid (VIA) testing, visual inspection with Lugol's iodine (VILI), primary HPV testing, and conventional Pap smear in detecting CIN2+ among non-pregnant women aged 30-65 in LMICs between 1990 and 2020.

DESIGN

Systematic review and meta-analysis.

SETTING AND PARTICIPANTS

Low- and middle-income countries, non-pregnant women aged 30-65.

METHODS

CENTRAL (Cochrane Library), CINAHL, Embase, Global Health, PubMed, and Web of Science databases were systematically searched to identify studies evaluating the performance of cervical cancer screening methods in LMICs. A diagnostic test accuracy meta-analysis was conducted to evaluate the performance of 4 screening methods in detecting CIN2+ relative to biopsy or cytology reference standards. Pooled statistics for sensitivity, specificity, diagnostic odds ratios, and summary receiver operating characteristic curves were determined for each method. Subgroup analyses were performed to examine whether there was variation in performance based on different reference standards for defining CIN2+, specifically: colposcopy-directed biopsy, biopsy alone, colposcopy alone, or liquid-based cytology.

RESULTS

Eighteen studies were identified through systematic review. Twelve studies were included in meta-analysis; 11 were cross-sectional and 1 was a randomized controlled clinical trial. The remaining six of the eighteen studies were inclided in a narrative syntehsis. Pooled estimates for sensitivity for VIA, VILI, primary HPV testing, and conventional Pap smear were 72.3%, 64.5%, 79.5%, and 60.2%, respectively; pooled estimates for specificity were 74.5%, 68.5%, 72.6%, and 97.4%, respectively; the diagnostic odds ratios were 7.31, 3.73, 10.42, 69.48, respectively; and the area under the summary receiver operating characteristic curves were 0.766, 0.647, 0.959, and 0.818, respectively. Performance of the screening method varied based on the reference standard used; pooled estimates using either colposcopy-directed biopsy or biopsy alone as the reference standard generally reported lower estimates; pooled estimates using either colposcopy alone or liquid-based cytology as references reported higher estimates.

CONCLUSIONS AND IMPLICATIONS

This meta-analysis found primary HPV testing to be the highest performing cervical cancer screening method in accurately identifying or excluding CIN2+. Further evaluation of performance at different CIN thresholds is warranted.

Diagnostic accuracy of cervical cancer screening strategies for high-grade cervical intraepithelial neoplasia (CIN2+/CIN3+) among women living with HIV: A systematic review and meta-analysis

BACKGROUND

We systematically reviewed the diagnostic accuracy of cervical cancer screening and triage strategies in women living with HIV (WLHIV).

METHODS

Cochrane Library, Embase, Global Health and Medline were searched for randomised controlled trials, prospective or cross-sectional studies published from database inception to 15 July 2022 reporting diagnostic accuracy of tests in cervical cancer screening and triage of screen-positive WLHIV. Studies were included if they reported the diagnostic accuracy of any cervical cancer screening or triage strategies for the detection of histologically-confirmed high-grade cervical intraepithelial neoplasia (CIN2+/CIN3+) among WLHIV. Summary data were extracted from published reports. Authors were contacted for missing data where applicable. Sensitivity and specificity estimates for CIN2/3+ were pooled using models for meta-analysis of diagnostic accuracy data. Study quality was assessed using the QUADAS-2 tool for the quality assessment of diagnostic accuracy studies. PROSPERO registration:CRD42020189031.

FINDINGS

In 38 studies among 18,737 WLHIV, the majority (n=19) were conducted in sub-Saharan Africa. The pooled prevalence was 12.0% (95%CI:9.8-14.1) for CIN2+ and 6.7% (95%CI:5.0-8.4) for CIN3+. The proportion of screen-positive ranged from 3-31% (visual inspection using acetic acid[VIA]); 2-46% (high-grade squamous intraepithelial lesions, and greater [HSIL+] cytology); 20-64% (high-risk[HR]-HPV DNA). In 14 studies, sensitivity and specificity of VIA were variable limiting the reliability of pooled estimates. In 5 studies where majority had histology-confirmed CIN2+, pooled sensitivity was 56.0% (95%CI:45.4-66.1; I²=65%) for CIN2+ and 65.0% (95%CI:52.9-75.4; I² =42%) for CIN3+; specificity for <CIN2 was 73.8% (95%CI:59.8-84.2, I²=94%). Cytology was similarly variable (sensitivity of ASCUS+ for CIN2+ range: 58-100%; specificity: 9-96%). In 28 studies, sensitivity of tests targeting 14-HR-HPV types was high (91.6%, 95%CI:88.1-94.1; I²=45% for CIN2+ and 92.5%, 95%CI:88.4-95.2; I²=32%) for CIN3+); but specificity for <CIN2 was low (62.2% (95%CI:57.9-66.4;I²=92%). Restriction to 8-HR-HPV increased specificity (65.8%; Relative specificity[RSpec] vs. 14-HR-HPV=1.17; 95%CI:1.10-1.24) with no significant change in sensitivity (CIN2+:85.5%; Relative Sensitivity[RSens]=0.94, 95%CI: 0.89-1.00; CIN3+:90%; RSens=0.96, 95%CI:0.89-1.03). VIA triage of 14-HR-HPV positive women decreased sensitivity for CIN2+ compared to HPV-DNA test alone (64.4% vs. 91.6%; RSens=0.68, 95%CI:0.62-0.75).

INTERPRETATION

HPV-DNA based approaches consistently showed superior sensitivity for CIN2+/CIN3+ compared to VIA or cytology. The low specificity of HPV-DNA based methods targeting up to 14-HR-HPV could be improved significantly by restricting to 8-HR-HPV with only minor losses in sensitivity, limiting requirement for triage for which optimal approaches are less clear.

FUNDING

World Health Organisation; National Cancer Institute; European Union's Horizon 2020 and Marie Skłodowska-Curie Actions programme.

Diagnostic accuracy for alternative cervical cancer screening strategies: A systematic review and meta-analysis

We performed a systematic review and meta-analysis to evaluate the accuracy of screening cervical cancer tests as alternative standalone methods. The combined estimates of sensitivity of visual inspection with acetic acid, visual inspection with lugol's iodine, conventional pap smear, liquid-based cytology, High risk HPV testing by clinician, High risk HPV testing by self- sampling, cervicography were 64%, 80%, 55%, 70%, 70% and 67% respectively; the combine values of specificity of these screening strategies were 88%, 88%, 96%, 59%, 94%, and 95% respectively. Our findings draw attention to an attractive opinion to facilitate the collection of specimens for DNA HPV by patients in settings where they don't have access to a regular screening programs.

High resolution multispectral endoscopy significantly improves the diagnostic accuracy of cervical intraepithelial lesions

Colposcopy is a visual technique to examine the cervix and determine selection of sites for biopsies and eligibility for treatment. It's always been a critical part of identifying preinvasive and early invasive cervical carcinoma. Unfortunately, challenges exist with regards to the accuracy of traditional colposcopy. Hence, to fully exploit the benefit of increasing diagnostic sensitivity, there is a pressing need to improve the performance of colposcopy by applying novel innovations and techniques. In this case report, we used a recently developed, high-resolution multispectral endoscopy and evaluated its performance by comparing colposcopic image features (the vascular pattern, in particular, depending upon the improved optics and illumination) with histology results. High-resolution multispectral endoscopy makes it easier to distinguish the features of pathological vessels, so that it has a higher sensitivity and specificity to detect cervical lesions, especially in discriminating the vascular pattern using multispectral technology.

Visual techniques for cervical cancer screening in Colombia

Introduction: Direct visual inspection for cervical cancer screening remains controversial, whereas colposcopy-biopsy is considered the gold standard for diagnosis of preneoplastic cervical lesions.Objectives: To determine the rates of cervical intraepithelial neoplasia grade 2 or more and of false positives for colposcopy and direct visual inspection.Materials and methods: Women aged 25-59 underwent direct visual inspection with acetic acid (VIA), Lugol’s iodine (VIA-VILI), and colposcopy. Punch biopsies were obtained for all positive tests. Using histology as the gold standard, detection and false positive rates were compared for VIA, VIA-VILI, and colposcopy (two thresholds). Sensitivity and false positive ratios with the corresponding 95% confidence intervals were estimated.Results: We included 5,011 women in the analysis and we obtained 602 biopsies. Positivity rates for colposcopy high-grade and low-grade diagnosis were 1.6% and 10.8%. Positivity rates for VIA and VIA-VILI were 7.4% and 9.9%. VIA showed a significantly lower detection rate than colposcopy with low-grade diagnosis as the threshold (SR=0.72; 95% CI 0.57-0.91), and significantly lower false positive rate (FPR=0.70; 95% CI 0.65-0.76). No differences between VIA-VILI and colposcopy low-grade threshold were observed. VIA and VIA-VILI showed significantly higher detection and false positive rates than colposcopy high-grade threshold. Sensitivity rates for visual inspection decreased with age and false positive rates increased. For all age groups, false positive rates for VIA and VIA-VILI were significantly higher than colposcopy.Conclusions: Detection rates for VIA-VILI similar to colposcopy low-grade threshold represent a chance to reduce cervical cancer mortality through see-and-treat approaches among women with limited access to health care. Lower detection rates suggest reviewing high-grade colposcopy findings as the threshold for biopsy in certain settings.

Risk of high-risk human papillomavirus infection and cervical precancerous lesions with past or current trichomonas infection: a pooled analysis of 25,054 women in rural China

BACKGROUND

Trichomonas vaginitis (TV) infection has obviously been implicated in gynecological morbidity but still unclear in cervical lesions.

OBJECTIVE

To evaluate the risk of hr-HPV infection and cervical intraepithelial neoplasia grade 2 or worse (CIN2 + ) by TV infection.

STUDY DESIGN

The pooled study was conducted among 12 population-based, cervical cancer screening studies throughout China (N = 24,054). HPV was detected by Hybrid Capture^®2 (HC2) test. Past TV infection was measured by self-reporting, current TV infection was diagnosed by liquid-based cytology (LBC), cervical lesions was diagnosed by histopathology.

RESULTS

Respective prevalence of hr-HPV and CIN2+ were 17.4% and 3.3%. Out of 24,054 women, 14.6% reported past TV infection, and out of 11,853 women, 9.9% had current TV infection. Current TV-positive women had an increased risk for hr-HPV (OR 1.31, 95%CI: 1.11-1.56). The risk of CIN2+ decreased for hr-HPV positive women with current TV infection (adjusted OR 0.50, 95% CI: 0.30-0.84) and past TV infection (adjusted OR 0.68, 95% CI: 0.54-0.86). Among hr-HPV negative women, no significant associations were observed between past or current TV infection and risk of CIN2+.

CONCLUSIONS

Women infected with HPV are more likely to be infected by other types of sexually transmitted diseases. Current TV-positive women had an increased risk for hr-HPV infection compared to currently TV-negative women. Both past and current TV-positive women had a decreased risk for CIN2+, especially among high-risk HPV positive women. More direct investigation into the interaction between TV, HPV, inflammatory signals, and risk of carcinogenesis are further needed.

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.

Role of active and passive smoking in high-risk human papillomavirus infection and cervical intraepithelial neoplasia grade 2 or worse

Objective

We performed a pooled analysis to examine cigarette smoking and household passive smoke exposure in relation to the risk of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia grade 2+ (CIN2+).

Methods

Data were pooled from 12 cross-sectional studies for cervical cancer screenings from 10 provinces of China in 1999–2007. A total of 16,422 women were analyzed, along with 2,392 high-risk-HPV (hr-HPV) positive women and 381 CIN2+ cases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression models controlling for sexual and non-sexual confounding factors.

Results

There was an excess risk between active smoking and hr-HPV infection and CIN2+. Adjusted OR for ever smokers vs. never smokers was 1.45 (95% CI=1.10–1.91), for hr-HPV infection and 1.89 (95% CI=1.03–3.44), for CIN2+. Passive smoking had a slightly increased risk on the hr-HPV infection with adjusted OR 1.11 (1.00–1.24), but no statistical association was observed between passive smoke exposure and CIN2+. Compared with the neither active nor passive smokers, both active and passive smokers had a 1.57-fold (95% CI=1.14–2.15) increased risk of HPV infection and a 1.99-fold (95% CI=1.02–3.88) risk of CIN2+.

Conclusion

Our large multi-center cross-sectional study found active smoking could increase the risk of overall hr-HPV infection and CIN2+ adjusted by passive smoking and other factors. Passive smoking mildly increased the risk of HPV infection but not the CIN2+. An interaction existed between passive tobacco exposure and active smoking for hr-HPV infection and the CIN2+.

Estimating long-term clinical effectiveness and cost-effectiveness of HPV 16/18 vaccine in China

BACKGROUND

Human papillomavirus (HPV) 16 and 18 are the two most common HPV oncogenic types that can be prevented by vaccination. This study aimed at assessing the cost-effectiveness of 3 doses of the bivalent HPV vaccine in rural and urban settings in China.

METHODS

A Markov model was adapted to reflect the lifetime of a modelled 100,000 12-year-old girls cohort in rural and urban settings in China. Input parameters were obtained from published literature, official reports and a two-round expert review panel. Clinical and economic outcomes of vaccination at age 12 with screening was compared to screening only. In the base case analysis, a 3 % discount rate, the vaccine cost of 247 CNY (US$ 39, PAHO vaccine cost in 2013), two rounds of screening in a life time and 70 % coverage for both screening and vaccination were used. One-way, two-way and probabilistic sensitivity analyses were performed. We used different thresholds of cost-effectiveness to reflect the diversity of economic development in China.

RESULTS

Vaccination in addition to screening could prevent 60 % more cervical cancer cases and deaths than screening only. The incremental cost effectiveness ratio varied largely when changing cost of vaccination and discount in one way analysis. Vaccination was very cost-effective when the vaccine cost ranged 87-630 CNY (US$ 13.8-100) in rural and 87-750 CNY (US$ 13.8-119) in urban; and remained cost-effective when the vaccine cost ranged 630-1,700 CNY (US$ 100-270) in rural and 750-1,900 CNY (US$ 119-302) in urban in two way analysis. Probabilistic sensitivity analyses showed that model results were robust.

CONCLUSIONS

In both rural and urban, the vaccination cost and discounting are important factors determining the cost-effectiveness of HPV vaccination; policy makers in China should take these into account when making a decision on the introduction of HPV vaccine. In areas with a high burden of cervical cancer and limited screening activities, HPV vaccination should be prioritized. However, the vaccine cost needs to be reduced in order to make it very cost-effective and affordable as well, in particular in poverty areas with high disease burden.

Evaluation of hybrid algorithm for analysis of scattered light using ex vivo nuclear morphology measurements of cervical epithelium

We evaluate a new hybrid algorithm for determining nuclear morphology using angle-resolved low coherence interferometry (a/LCI) measurements in ex vivo cervical tissue. The algorithm combines Mie theory based and continuous wavelet transform inverse light scattering analysis. The hybrid algorithm was validated and compared to traditional Mie theory based analysis using an ex vivo tissue data set. The hybrid algorithm achieved 100% agreement with pathology in distinguishing dysplastic and non-dysplastic biopsy sites in the pilot study. Significantly, the new algorithm performed over four times faster than traditional Mie theory based analysis.

Accuracy of Colposcopically Directed Biopsy: Results from an Online Quality Assurance Programme for Colposcopy in a Population-Based Cervical Screening Setting in Italy

PURPOSE

To report the accuracy of colposcopically directed biopsy in an internet-based colposcopy quality assurance programme in northern Italy.

METHODS

A web application was made accessible on the website of the regional Administration. Fifty-nine colposcopists out of the registered 65 logged in, viewed a posted set of 50 digital colpophotographs, classified them for colposcopic impression and need for biopsy, and indicated the most appropriate site for biopsy with a left-button mouse click on the image.

RESULTS

Total biopsy failure rate, comprising both nonbiopsy and incorrect selection of biopsy site, was 0.20 in CIN1, 0.11 in CIN2, 0.09 in CIN3, and 0.02 in carcinoma. Errors in the selection of biopsy site were stable between 0.08 and 0.09 in the three grades of CIN while decreasing to 0.01 in carcinoma. In multivariate analysis, the risk of incorrect selection of biopsy site was 1.97 for CIN2, 2.52 for CIN3, and 0.29 for carcinoma versus CIN1.

CONCLUSIONS

Although total biopsy failure rate decreased regularly with increasing severity of histological diagnosis, the rate of incorrect selection of biopsy site was stable up to CIN3. In multivariate analysis, CIN2 and CIN3 had an independently increased risk of incorrect selection of biopsy site.

An online quality assurance program for colposcopy in a population-based cervical screening setting in Italy: results on colposcopic impression

OBJECTIVE

To report the results of an Internet-based colposcopy quality assurance program from a population-based cervical screening service in a large region of northern Italy.

METHODS

In 2010 to 2011, a Web application was made accessible on the Web site of the regional administration. Fifty-nine colposcopists of the registered 65 participated. They logged-in, viewed a posted set of 50 high-quality digital colpophotographs selected by an expert committee, and rated them for colposcopic impression using a 4-tier classification (Negative; abnormal, grade 1 [G1]; abnormal, grade 2 [G2]; suspected invasive cancer [Cancer]) derived from the International Federation for Cervical Pathology and Colposcopy 2002 classification. kappa (κ) coefficients for intercolposcopist agreement and colposcopist-committee agreement were calculated.

RESULTS

Colposcopist-committee agreement was greater than intercolposcopist agreement (overall κ 0.69 vs 0.60, p<.001). The κ values for colposcopist-committee agreement were 0.83 on Negative, 0.53 on G1, 0.66 on G2, and 0.80 on Cancer (all p values for pairwise comparisons<.001, except for Negative vs Cancer [p=.078]). There was no systematic tendency for colposcopists to underestimate or overestimate the colposcopic findings (2-tailed sign test, p=.13). Overall colposcopist-committee agreement was greater among patients 35 years or older (p<.001) and for colposcopists with previous quality assurance experiences (p<.01). Only 0.2% of Negative impressions were formulated for a cervical intraepithelial neoplasia grade 2 or worse. As a parallel finding, the impression of Cancer predicted cervical intraepithelial neoplasia grade 2 or less in 0.5% of cases. The histologic substrates of G1 were dispersed over a large spectrum.

CONCLUSIONS

The reproducibility of colposcopic impression, when classified by trained colposcopists examining high-quality images, is higher than is generally thought.

Clinical application of DNA ploidy to cervical cancer screening: A review

Screening for cervical cancer with DNA ploidy assessment by automated quantitative image cytometry has spread throughout China over the past decade and now an estimated 1 million tests per year are done there. Compared to conventional liquid based cytology, DNA ploidy has competitive accuracy with much higher throughput per technician. DNA ploidy has the enormous advantage that it is an objective technology that can be taught in typically 2 or 3 wk, unlike qualitative cytology, and so it can enable screening in places that lack sufficient qualified cytotechnologists and cytopathologists for conventional cytology. Most papers on experience with application of the technology to cervical cancer screening over the past decade were published in the Chinese language. This review aims to provide a consistent framework for analysis of screening data and to summarize some of the work published from 2005 to the end of 2013. Of particular interest are a few studies comparing DNA ploidy with testing for high risk human papilloma virus (hrHPV) which suggest that DNA ploidy is at least equivalent, easier and less expensive than hrHPV testing. There may also be patient management benefits to combining hrHPV testing with DNA ploidy. Some knowledge gaps are identified and some suggestions are made for future research directions.

Evaluation of stationary colposcope and the Gynocular, by the Swede score systematic colposcopic system in VIA positive women: a crossover randomized trial

Objective

This study aimed to evaluate cervical lesions by the Swede coloscopy system, histologic finding, liquid-based cytology, and human papillomavirus (HPV) in women who resulted positive for visual inspection of the cervix with acetic acid (VIA) by using a pocket-sized battery-driven colposcope, the Gynocular (Gynius AB, Sweden).

Methods

This study was a crossover, randomized clinical trial at the colposcopy clinic of Bangabandhu Sheikh Mujib Medical University in Dhaka, Bangladesh, with 540 VIA-positive women. Swede scores were obtained by the Gynocular and stationary colposcope, as well as samples for liquid-based cytology, HPV, and cervical biopsies. The Swede scores were compared against the histologic diagnosis and used as criterion standard. The percentage agreement and the κ statistic for the Gynocular and standard colposcope were also calculated.

Results

The Gynocular and stationary colposcope showed high agreement in Swede scores with a κ statistic of 0.998, P value of less than 0.0001, and no difference in detecting cervical lesions in biopsy. Biopsy detected cervical intraepithelial neoplasia (CIN) 2+ (CIN2, CIN3, and invasive cancer) in 38 (7%) of the women, whereas liquid-based cytology detected CIN2+ in 13 (2.5%) of the women. Forty-four (8.6%) women who were tested resulted positive for HPV; 20 (3.9%) women had HPV-16, 2 (0.4%) had HPV-18, and 22 (4.3%) had other high-risk HPV.

Conclusions

Our study showed that few VIA-positive women had CIN2+ lesions or HPV infection. Colposcopy by Swede score identified significantly more CIN2+ lesions than liquid-based cytology and could offer a more accurate screening and selection for immediate treatment of cervical lesions in low-resource settings.

Liquid-based cytology and human papillomavirus testing: a pooled analysis using the data from 13 population-based cervical cancer screening studies from China

OBJECTIVE

The objective of this study was to evaluate the impact of introducing HR-HPV testing in cytology regarding cervical cancer screening practice.

METHODS

A pooled analysis of liquid-based cytology (LBC) and HR-HPV testing using data from 13 population-based cervical cancer screening studies conducted in China was performed. Participants (n=25,404) received LBC and HR-HPV testing. Women found to be positive on screening were referred for colposcopy and biopsy. The effectiveness of screening strategies that use: LBC with HR-HPV triage for atypical squamous cells of undetermined significance (ASC-US), HR-HPV testing with cytology triage for HPV positive tests, or LBC and HPV cotesting was compared with that of LBC screening alone.

RESULTS

LBC with HR-HPV triage for ASC-US had similar sensitivity compared with LBC alone, but significantly increased specificity for both cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and CIN3 or worse (CIN3+) endpoints, and had the best balance between sensitivity and specificity among the strategies. LBC and HR-HPV cotesting had the highest sensitivity and negative predictive value (NPV) and could permit a safe extension of screening intervals. Through the use of an immediate colposcopy threshold of ASC-US or worse for HR-HPV positive women and the use of a raised threshold of low-grade squamous intraepithelial lesion (LSIL) or worse for HR-HPV negative women, LBC and HR-HPV cotesting could provide the same effectiveness as LBC testing with HR-HPV triage for ASC-US at baseline tests.

CONCLUSIONS

The results of the current study support the use of the cervical cancer screening guidelines in China.

A systematic review classifies sources of bias and variation in diagnostic test accuracy studies

OBJECTIVE

To classify the sources of bias and variation and to provide an updated summary of the evidence of the effects of each source of bias and variation.

STUDY DESIGN AND SETTING

We conducted a systematic review of studies of any design with the main objective of addressing bias or variation in the results of diagnostic accuracy studies. We searched MEDLINE, EMBASE, BIOSIS, the Cochrane Methodology Register, and Database of Abstracts of Reviews of Effects (DARE) from 2001 to October 2011. Citation searches based on three key papers were conducted, and studies from our previous review (search to 2001) were eligible. One reviewer extracted data on the study design, objective, sources of bias and/or variation, and results. A second reviewer checked the extraction.

RESULTS

We summarized the number of studies providing evidence of an effect arising from each source of bias and variation on the estimates of sensitivity, specificity, and overall accuracy.

CONCLUSIONS

We found consistent evidence for the effects of case-control design, observer variability, availability of clinical information, reference standard, partial and differential verification bias, demographic features, and disease prevalence and severity. Effects were generally stronger for sensitivity than for specificity. Evidence for other sources of bias and variation was limited.

Pooled analysis of the performance of liquid-based cytology in population-based cervical cancer screening studies in China

BACKGROUND

Liquid-based cytology (LBC) has been widely used for cervical cancer screening. Despite numerous studies and systematic reviews, to the authors' knowledge few large studies to date have focused on biopsy-confirmed cervical lesions and controversy remains concerning its diagnostic accuracy. The objective of the current study was to assess LBC for detecting biopsy-confirmed cervical intraepithelial neoplasia (CIN) and cancer.

METHODS

A pooled analysis of LBC using data from 13 population-based, cross-sectional, cervical cancer screening studies performed in China from 1999 to 2008 was performed. Participants (n = 26,782) received LBC and human papillomavirus testing. Women found to be positive on screening were referred for colposcopy and biopsy. The accuracy of LBC for detecting biopsy-confirmed CIN of type 2 or worse (CIN2+) as well as CIN type 3 or worse (CIN3+) lesions was analyzed.

RESULTS

Of 25,830 women included in the analysis, CIN2+ was found in 107 of 2612 with atypical squamous cells (4.1%), 142 of 923 with low-grade squamous intraepithelial neoplasia (15.4%), 512 of 784 with high-grade squamous intraepithelial neoplasia (65.3%), 29 of 30 with squamous cell carcinoma (96.7%), 4 of 27 with atypical glandular cells (14.8%), and 85 of 21,454 with normal cytology results (0.4%). No invasive cancers were found to have atypical squamous cells, atypical glandular cells, or cytologically normal slides. The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of LBC for detecting CIN2+ were 81.0%, 95.4%, 38.3%, 99.3 %, and 94.9%, respectively. Although Hybrid Capture 2 was more sensitive than LBC, the specificity, positive predictive value, and overall accuracy of LBC were higher than those of Hybrid Capture2 at 85.2%, 18.6%, and 85.5%, respectively.

CONCLUSIONS

The results of the current study indicate that the performance of LBC can effectively predict the risk of existing CIN2+ and may be a good screening tool for cervical cancer prevention in a developing country.

A population-based study of visual inspection with acetic acid (VIA) for cervical screening in rural Nigeria

OBJECTIVE

Cervical cancer is the most common gynecological cancer in developing countries. Visual inspection with acetic acid (VIA) was introduced to screen for cervical premalignant lesions in developing countries owing to the inability of many countries to implement high-quality cytologic services. We sought to compare VIA performance among different health workers in Nigeria.

METHODS

In a population-based project, 7 health workers who had been screening women with VIA for approximately 2 years at local government health centers in rural Nigeria were retrained in a 2-week program using the International Agency for Research on Cancer training manual. Women from a rural village who had never had cervical cancer screening were recruited into the study. Each woman had cervical cancer screening by VIA, liquid-based cytologic test, and oncogenic human papillomavirus (HPV) DNA test.

RESULTS

Despite similar participant characteristics, across all age groups, providers had wide ranges of VIA results; 0% to 21% suspect cancer and 0% to 25% were VIA positive. Visual inspection with acetic acid was insensitive compared to a combination of cytologic and HPV tests.

CONCLUSION

In our study, VIA was not reproducible, nor was it sensitive compared to cytologic and HPV tests.

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.

Asia oceania guidelines for the implementation of programs for cervical cancer prevention and control

This paper aims to provide evidence-based recommendations for health professionals, to develop a comprehensive cervical cancer program for a clinic, a community, or a country. Ensuring access to healthcare is the responsibility of all societies, and the Asia Oceania Research Organisation in Genital Infections and Neoplasia (AOGIN) is committed to working collaboratively with governments and health professionals to facilitate prevention programs, to protect girls and women from cervical cancer, a disease that globally affects 500,000 and kills nearly 300,000 women annually, just over half of whom are in the Asia Oceania region. We share the vision that a comprehensive program of vaccination, screening, and treatment should be made accessible to all girls and women in the world. The primary purpose of these guidelines is to provide information on scientific evidence on the different modalities and approaches of cervical cancer prevention programs, for high resource and low resource settings. The secondary purpose is to provide an overview of the current situation of cervical cancer control and prevention in various Asian Oceania countries: their views of an ideal program, identified obstacles, and suggestions to overcome them are discussed.

Costs of cervical cancer screening and treatment using visual inspection with acetic acid (VIA) and cryotherapy in Ghana: the importance of scale

OBJECTIVES

To estimate the incremental costs of visual inspection with acetic acid (VIA) and cryotherapy at cervical cancer screening facilities in Ghana; to explore determinants of costs through modelling; and to estimate national scale-up and annual programme costs.

METHODS

Resource-use data were collected at four out of six active VIA screening centres, and unit costs were ascertained to estimate the costs per woman of VIA and cryotherapy. Modelling and sensitivity analysis were used to explore the influence of observed differences between screening facilities on estimated costs and to calculate national costs.

RESULTS

Incremental economic costs per woman screened with VIA ranged from 4.93 US$ to 14.75 US$, and costs of cryotherapy were between 47.26 US$ and 84.48 US$ at surveyed facilities. Under base case assumptions, our model estimated the costs of VIA to be 6.12 US$ per woman and those of cryotherapy to be 27.96 US$. Sensitivity analysis showed that the number of women screened per provider and treated per facility was the most important determinants of costs. National annual programme costs were estimated to be between 0.6 and 4.0 million US$ depending on assumed coverage and adopted screening strategy.

CONCLUSION

  When choosing between different cervical cancer prevention strategies, the feasibility of increasing uptake to achieve economies of scale should be a major concern.

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.

Effectiveness of VIA, Pap, and HPV DNA testing in a cervical cancer screening program in a peri-urban community in Andhra Pradesh, India

Background

While many studies have compared the efficacy of Pap cytology, visual inspection with acetic acid (VIA) and human papillomavirus (HPV) DNA assays for the detection cervical intraepithelial neoplasia and cancer, few have evaluated the program effectiveness.

Methods and Findings

A population-based sample of 5603 women from Medchal Mandal in Andhra Pradesh, India were invited to participate in a study comparing Pap cytology, VIA, and HPV DNA screening for the detection of CIN3+. Participation in primary screening and all subsequent follow-up visits was rigorously tracked. A 20% random sample of all women screened, in addition to all women with a positive screening test result underwent colposcopy with directed biopsy for final diagnosis. Sensitivity, specificity, positive and negative predictive values were adjusted for verification bias. HPV testing had a higher sensitivity (100%) and specificity (90.6%) compared to Pap cytology (sensitivity  =  78.2%; specificity = 86.0%) and VIA (sensitivity = 31.6%; specificity = 87.5%). Since 58% of the sample refused involvement and another 28% refused colposcopy or biopsy, we estimated that potentially 87.6% of the total underlying cases of CIN3 and cancer may have been missed due to program failures.

Conclusions

We conclude that despite our use of available resources, infrastructure, and guidelines for cervical cancer screening implementation in resource limited areas, community participation and non-compliance remain the major obstacles to successful reduction in cervical cancer mortality in this Indian population. HPV DNA testing was both more sensitive and specific than Pap cytology and VIA. The use of a less invasive and more user-friendly primary screening strategy (such as self-collected swabs for HPV DNA testing) may be required to achieve the coverage necessary for effective reduction in cervical cancer mortality.