Automated Cervical Screening and Triage, Based on HPV Testing and Computer-Interpreted Cytology.

Background: State-of-the-art cervical cancer prevention includes human papillomavirus (HPV) vaccination among adolescents and screening/treatment of cervical precancer (CIN3/AIS and, less strictly, CIN2) among adults. HPV testing provides sensitive detection of precancer but, to reduce overtreatment, secondary "triage" is needed to predict women at highest risk. Those with the highest-risk HPV types or abnormal cytology are commonly referred to colposcopy; however, expert cytology services are critically lacking in many regions. Methods: To permit completely automatable cervical screening/triage, we designed and validated a novel triage method, a cytologic risk score algorithm based on computer-scanned liquid-based slide features (FocalPoint, BD, Burlington, NC). We compared it with abnormal cytology in predicting precancer among 1839 women testing HPV positive (HC2, Qiagen, Germantown, MD) in 2010 at Kaiser Permanente Northern California (KPNC). Precancer outcomes were ascertained by record linkage. As additional validation, we compared the algorithm prospectively with cytology results among 243 807 women screened at KPNC (2016-2017). All statistical tests were two-sided. Results: Among HPV-positive women, the algorithm matched the triage performance of abnormal cytology. Combined with HPV16/18/45 typing (Onclarity, BD, Sparks, MD), the automatable strategy referred 91.7% of HPV-positive CIN3/AIS cases to immediate colposcopy while deferring 38.4% of all HPV-positive women to one-year retesting (compared with 89.1% and 37.4%, respectively, for typing and cytology triage). In the 2016-2017 validation, the predicted risk scores strongly correlated with cytology (P < .001). Conclusions: High-quality cervical screening and triage performance is achievable using this completely automated approach. Automated technology could permit extension of high-quality cervical screening/triage coverage to currently underserved regions.

Validation of a Human Papillomavirus (HPV) DNA Cervical Screening Test That Provides Expanded HPV Typing.

As cervical cancer screening shifts from cytology to human papillomavirus (HPV) testing, a major question is the clinical value of identifying individual HPV types. We aimed to validate Onclarity (Becton Dickinson Diagnostics, Sparks, MD), a nine-channel HPV test recently approved by the FDA, by assessing (i) the association of Onclarity types/channels with precancer/cancer; (ii) HPV type/channel agreement between the results of Onclarity and cobas (Roche Molecular Systems, Pleasanton, CA), another FDA-approved test; and (iii) Onclarity typing for all types/channels compared to typing results from a research assay (linear array [LA]; Roche). We compared Onclarity to histopathology, cobas, and LA. We tested a stratified random sample (n = 9,701) of discarded routine clinical specimens that had tested positive by Hybrid Capture 2 (HC2; Qiagen, Germantown, MD). A subset had already been tested by cobas and LA (n = 1,965). Cervical histopathology was ascertained from electronic health records. Hierarchical Onclarity channels showed a significant linear association with histological severity. Onclarity and cobas had excellent agreement on partial typing of HPV16, HPV18, and the other 12 types as a pool (sample-weighted kappa value of 0.83); cobas was slightly more sensitive for HPV18 and slightly less sensitive for the pooled high-risk types. Typing by Onclarity showed excellent agreement with types and groups of types identified by LA (kappa values from 0.80 for HPV39/68/35 to 0.97 for HPV16). Onclarity typing results corresponded well to histopathology and to an already validated HPV DNA test and could provide additional clinical typing if such discrimination is determined to be clinically desirable.

Low Risk of Cervical Cancer/Precancer Among Most Women Under Surveillance Postcolposcopy.

OBJECTIVE: To inform impending postcolposcopy guidelines, this analysis examined the subsequent risk of CIN 3+ among women with a grade lower than CIN 2 (< CIN 2) colposcopy results, taking into account the referring results that brought them to colposcopy and cotest results postcolposcopy. METHODS: We analyzed 107,005 women from 25 to 65 years old, recommended for colposcopy at Kaiser Permanente Northern California. We estimated absolute risks of CIN 3+ among women: (1) recommended for colposcopy (precolposcopy), (2) following colposcopy and with histology results < CIN 2 (postcolposcopy), and (3) with cotest results 12 months after a < CIN 2 colposcopy (return cotest). RESULTS: After colposcopy showing < CIN 2 (n = 69,790; 87% of the women at colposcopy), the 1-year risk of CIN 3+ was 1.2%, compared with 6.3% at the time of colposcopy recommendation. Negative cotest results 1 year after colposcopy identified a large group (37.1%) of women whose risk of CIN 3+ (i.e., <0.2% at 3 years after postcolposcopy cotest) was comparable with women with normal cytology in the screening population. These risks are consistent with current guidelines recommending repeat cotesting 12 months after colposcopy < CIN 2 and a 3-year return for women with a negative postcolposcopy cotest. CONCLUSIONS: Most women are at low risk of subsequent CIN 3+ after a colposcopy showing < CIN 2, especially those who are human papillomavirus-negative postcolposcopy, consistent with current management guidelines for repeat testing intervals. Before the finalizing the upcoming guidelines, we will consider additional rounds of postcolposcopy cotesting.

Clinical Outcomes after Conservative Management of Cervical Intraepithelial Neoplasia Grade 2 (CIN2) in Women Ages 21-39 Years.

Cervical intraepithelial neoplasia grade 2 (CIN2) frequently regresses, is typically slow-growing, and rarely progresses to cancer. Some women forgo immediate treatment, opting for conservative management (heightened surveillance with cytology and colposcopy), to minimize overtreatment and increased risk of obstetric complications; however, there are limited data examining clinical outcomes in these women. We performed a retrospective cohort analysis of younger women diagnosed with initially untreated CIN1/2, CIN2 and CIN2/3 lesions at Kaiser Permanente Northern California between 2003 and 2015. Clinical outcomes were categorized into five mutually exclusive hierarchical groups: cancer, treated, returned to routine screening, persistent high-grade lesion, or persistent low-grade lesion. Median follow-up for the 2,417 women was 48 months. Six women were diagnosed with cancer (0.2%), all with history of high-grade cytology, and none after a negative cotest. Thirty percent of women were treated, and only 20% returned to routine screening; 50% remained in continued intensive follow-up, of which 86% had either low-grade cytology/histology or high-risk human papillomavirus (HPV) positivity, but not necessarily persistence of a single HPV type. No cancers were detected after a single negative cotest in follow-up. Almost half of initially untreated women did not undergo treatment, but remained by protocol in colposcopy clinic for 2 or more years in the absence of persisting CIN2+ Their incomplete return to total negativity was possibly due to sequential new and unrelated low-grade abnormalities. The prolonged colposcopic surveillance currently required to return to routine screening in the absence of persisting CIN2+ might not be necessary after a negative cotest.Significance: Many younger women under conservative management following an initial CIN2 result remain in a clinical protocol of prolonged intensified surveillance without a subsequent diagnosis of CIN2 or more severe diagnoses. More research is needed to determine whether such prolonged management might be unnecessary following a negative cotest for those women with an initial CIN2 but otherwise only low-grade findings. Cancer Prev Res; 11(3); 165-70. ©2018 AACR.

Human Papillomavirus DNA Methylation as a Biomarker for Cervical Precancer: Consistency across 12 Genotypes and Potential Impact on Management of HPV-Positive Women.

Purpose: Human papillomavirus (HPV) DNA methylation testing is a promising triage option for women testing HPV positive during cervical cancer screening. However, the extent to which methylation indicates precancer for all 12 carcinogenic HPV types has not been evaluated.Experimental Design: In this nested case-control study, we tested up to 30 cases of precancer [cervical intraepithelial neoplasia grade 3 (CIN3)/adenocarcinoma in situ (AIS)] and 30 normal controls for each carcinogenic type (single infections with 16/18/31/33/35/39/45/51/52/56/58/59). Next-generation bisulfite sequencing was performed on CpG sites within the L1 and L2 genes. We calculated differences in methylation, ORs, and AUC. Using a fixed sensitivity of 80%, we evaluated the specificity and the risk of CIN3/AIS for best performing CpG sites, and compared the performance of an explorative multi-type methylation assay with current triage strategies.Results: Methylation was positively associated with CIN3/AIS across all 12 types. AUCs for the top sites ranged from 0.71 (HPV51 and HPV56) to 0.86 (HPV18). A combined 12-type methylation assay had the highest Youden index (0.46), compared with cytology (0.31) and a 5-type methylation assay, including only previously described types (0.26). The 12-type methylation assay had higher sensitivity (80% vs. 76.6%) and lower test positivity compared with cytology (38.5% vs. 48.7%). The risk of CIN3/AIS was highest for methylation positives and lowest for cytology or HPV16/18 positives.Conclusions: HPV DNA methylation is a general phenomenon marking the transition from HPV infection to precancer for all 12 carcinogenic types. Development of a combined multitype methylation assay may serve as a triage test for HPV-positive women. Clin Cancer Res; 24(9); 2194-202. ©2018 AACR.

Epidemiologic Evidence That Excess Body Weight Increases Risk of Cervical Cancer by Decreased Detection of Precancer.

Purpose Obesity has been inconsistently linked to increased cervical cancer incidence and mortality; however, the effect of obesity on cervical screening has not been explored. We investigated the hypothesis that increased body mass might decrease detection of cervical precancer and increase risk of cervical cancer even in women undergoing state-of-the-art screening. Methods We conducted a retrospective cohort study of 944,227 women age 30 to 64 years who underwent cytology and human papillomavirus DNA testing (ie, cotesting) at Kaiser Permanente Northern California (January 2003 to December 2015). Body mass index was categorized as normal/underweight (< 25 kg/m2), overweight (25 to < 30 kg/m2), or obese (≥ 30 kg/m2). We estimated 5-year cumulative risks of cervical precancer and cancer by category of body mass index using logistic Weibull survival models. Results We observed lower risk of cervical precancer (n = 4,489) and higher risk of cervical cancer (n = 490) with increasing body mass index. Specifically, obese women had the lowest 5-year risk of precancer (0.51%; 95% CI, 0.48% to 0.54% v 0.73%; 95% CI, 0.70% to 0.76% in normal/underweight women; P trend < .001). In contrast, obese women had the highest 5-year risk of cancer (0.083%; 95% CI, 0.072% to 0.096% v 0.056%; 95% CI, 0.048% to 0.066% in normal/underweight women; P trend < .001). Results were consistent in subgroups defined by age (30 to 49 v 50 to 64 years), human papillomavirus status (positive v negative), and histologic subtype (glandular v squamous). Approximately 20% of cervical cancers could be attributed to overweight or obesity in the women in our study who underwent routine cervical screening. Conclusion In this large, screened population, overweight and obese women had an increased risk of cervical cancer, likely because of underdiagnosis of cervical precancer. Improvements in equipment and/or technique to assure adequate sampling and visualization of women with elevated body mass might reduce cervical cancer incidence.

Effect of Several Negative Rounds of Human Papillomavirus and Cytology Co-testing on Safety Against Cervical Cancer: An Observational Cohort Study.

Background: Current U.S. cervical cancer screening and management guidelines do not consider previous screening history, because data on multiple-round human papillomavirus (HPV) and cytology "co-testing" have been unavailable. Objective: To measure cervical cancer risk in routine practice after successive negative screening co-tests at 3-year intervals. Design: Observational cohort study. Setting: Integrated health care system (Kaiser Permanente Northern California, Oakland, California). Patients: 990 013 women who had 1 or more co-tests from 2003 to 2014. Measurements: 3- and 5-year cumulative detection of (risk for) cervical intraepithelial neoplasia grade 3, adenocarcinoma in situ, and cervical cancer (≥CIN3) in women with different numbers of negative co-tests, overall and within subgroups defined by previous co-test results or baseline age. Results: Five-year ≥CIN3 risks decreased after each successive negative co-test screening round (0.098%, 0.052%, and 0.035%). Five-year ≥CIN3 risks for an HPV-negative co-test, regardless of the cytology result, nearly matched the performance (reassurance) of a negative co-test for each successive round of screening (0.114%, 0.061%, and 0.041%). By comparison, ≥CIN3 risks for the cytology-negative co-test, regardless of the HPV result, also decreased with each successive round, but 3-year risks were as high as 5-year risks after an HPV-negative co-test (0.199%, 0.065%, and 0.043%). No interval cervical cancer cases were diagnosed after the second negative co-test. Independently, ≥CIN3 risks decreased with age. Length of previous screening interval did not influence future ≥CIN3 risks. Limitation: Interval-censored observational data. Conclusion: After 1 or more negative cervical co-tests (or HPV tests), longer screening intervals (every 5 years or more) might be feasible and safe. Primary Funding Source: National Cancer Institute Intramural Research Program.

Relative Performance of HPV and Cytology Components of Cotesting in Cervical Screening.

Background: The main goal of cervical screening programs is to detect and treat precancer before cancer develops. Human papillomavirus (HPV) testing is more sensitive than cytology for detecting precancer. However, reports of rare HPV-negative, cytology-positive cancers are motivating continued use of both tests (cotesting) despite increased testing costs. Methods: We quantified the detection of cervical precancer and cancer by cotesting compared with HPV testing alone at Kaiser Permanente Northern California (KPNC), where 1 208 710 women age 30 years and older have undergone triennial cervical cotesting since 2003. Screening histories preceding cervical cancers (n = 623) and precancers (n = 5369) were examined to assess the relative contribution of the cytology and HPV test components in identifying cases. The performances of HPV testing and cytology were compared using contingency table methods, general estimating equation models, and nonparametric statistics; all statistical tests were two-sided. Results: HPV testing identified more women subsequently diagnosed with cancer (P < .001) and precancer (P < .001) than cytology. HPV testing was statistically significantly more likely to be positive for cancer at any time point (P < .001), except within 12 months (P = .10). HPV-negative/cytology-positive results preceded only small fractions of cases of precancer (3.5%) and cancer (5.9%); these cancers were more likely to be regional or distant stage with squamous histopathology than other cases. Given the rarity of cancers among screened women, the contribution of cytology to screening translated to earlier detection of at most five cases per million women per year. Two-thirds (67.9%) of women found to have cancer during 10 years of follow-up at KPNC were detected by the first cotest performed. Conclusions: The added sensitivity of cotesting vs HPV alone for detection of treatable cancer affected extremely few women.

Challenges in risk estimation using routinely collected clinical data: The example of estimating cervical cancer risks from electronic health-records.

Electronic health-records (EHR) are increasingly used by epidemiologists studying disease following surveillance testing to provide evidence for screening intervals and referral guidelines. Although cost-effective, undiagnosed prevalent disease and interval censoring (in which asymptomatic disease is only observed at the time of testing) raise substantial analytic issues when estimating risk that cannot be addressed using Kaplan-Meier methods. Based on our experience analysing EHR from cervical cancer screening, we previously proposed the logistic-Weibull model to address these issues. Here we demonstrate how the choice of statistical method can impact risk estimates. We use observed data on 41,067 women in the cervical cancer screening program at Kaiser Permanente Northern California, 2003-2013, as well as simulations to evaluate the ability of different methods (Kaplan-Meier, Turnbull, Weibull and logistic-Weibull) to accurately estimate risk within a screening program. Cumulative risk estimates from the statistical methods varied considerably, with the largest differences occurring for prevalent disease risk when baseline disease ascertainment was random but incomplete. Kaplan-Meier underestimated risk at earlier times and overestimated risk at later times in the presence of interval censoring or undiagnosed prevalent disease. Turnbull performed well, though was inefficient and not smooth. The logistic-Weibull model performed well, except when event times didn't follow a Weibull distribution. We have demonstrated that methods for right-censored data, such as Kaplan-Meier, result in biased estimates of disease risks when applied to interval-censored data, such as screening programs using EHR data. The logistic-Weibull model is attractive, but the model fit must be checked against Turnbull non-parametric risk estimates.

Adherence patterns to extended cervical screening intervals in women undergoing human papillomavirus (HPV) and cytology cotesting.

Although guidelines have recommended extended interval cervical screening using concurrent human papillomavirus (HPV) and cytology ("cotesting") for over a decade, little is known about its adoption into routine care. Using longitudinal medical record data (2003-2015) from Kaiser Permanente Northern California (KPNC), which adopted triennial cotesting in 2003, we examined adherence to extended interval screening. We analyzed predictors of screening intervals among 491,588 women undergoing routine screening, categorizing interval length into early (<2.5years), adherent (2.5<3.5years), or late (3.5<6.0years). We also examined repeated early screening in a subgroup of 50,691 women. Predictors examined included: cohort year (defined by baseline cotest, 2003-2009), race/ethnicity, and baseline age. Compared to the 2003 cohort, women in the 2009 cohort were significantly less likely to screen early (aOR=0.22, 95% CI=0.21, 0.23) or late (aOR=0.47, 95% CI=0.45, 0.49). African American (AA) and Hispanic women were less adherent overall than Non-Hispanic White women, with increased early [(AA: aOR=1.21, 95%CI=1.17, 1.25) (Hispanic: aOR=1.08, 95%CI=1.06, 1.11)] and late screening [(AA: aOR=1.23, 95%CI=1.19, 1.27) (Hispanic: aOR=1.06, 95%CI=1.03, 1.08)]. Asian women were slightly more likely to screen early (aOR=1.03, 95%CI=1.01, 1.05), and less likely to screen late (aOR=0.92, 95% CI=0.90, 0.94). Women aged 60-64years were most likely to screen early for two consecutive intervals (aOR=2.09, 95%CI=1.91, 2.29). Our study found that widespread and rapid adoption of extended interval cervical cancer screening is possible, at least in this managed care setting. Further research examining multilevel drivers promoting or restricting extended interval screening across diverse healthcare settings is needed.

Risks of CIN 2+, CIN 3+, and Cancer by Cytology and Human Papillomavirus Status: The Foundation of Risk-Based Cervical Screening Guidelines.

OBJECTIVES: The next round of the American Society for Colposcopy and Cervical Pathology (ASCCP)-sponsored cervical cancer screening and management guidelines will recommend clinical actions based on risk, rather than test-based algorithms. This article gives preliminary risk estimates for the screening setting, showing combinations of the 2 most important predictors, human papillomavirus (HPV) status and cytology result. MATERIALS AND METHODS: Among 1,262,713 women aged 25 to 77 years co-tested with HC2 (Qiagen) and cytology at Kaiser Permanente Northern California, we estimated 0-5-year cumulative risk of cervical intraepithelial neoplasia (CIN) 2+, CIN 3+, and cancer for combinations of cytology (negative for intraepithelial lesion or malignancy [NILM], atypical squamous cells of undetermined significance [ASC-US], low-grade squamous intraepithelial lesion [LSIL], atypical squamous cells cannot exclude HSIL [ASC-H], high-grade squamous intraepithelial lesion [HSIL], atypical glandular cells [AGC]) and HPV status. RESULTS: Ninety percent of screened women had HPV-negative NILM and an extremely low risk of subsequent cancer. Five-year risks of CIN 3+ were lower after HPV negativity (0.12%) than after NILM (0.25%). Among HPV-negative women, 5-year risks for CIN 3+ were 0.10% for NILM, 0.44% for ASC-US, 1.8% for LSIL, 3.0% for ASC-H, 1.2% for AGC, and 29% for HSIL+ cytology (which was very rare). Among HPV-positive women, 5-year risks were 4.0% for NILM, 6.8% for ASC-US, 6.1% for LSIL, 28% for ASC-H, 30% for AGC, and 50% for HSIL+ cytology. CONCLUSIONS: As a foundation for the next guidelines revision, we confirmed with additional precision the risk estimates previously reported for combinations of HPV and cytology. Future analyses will estimate risks for women being followed in colposcopy clinic and posttreatment and will consider the role of risk modifiers such as age, HPV vaccine status, HPV type, and screening and treatment history.

Mixture models for undiagnosed prevalent disease and interval-censored incident disease: applications to a cohort assembled from electronic health records.

For cost-effectiveness and efficiency, many large-scale general-purpose cohort studies are being assembled within large health-care providers who use electronic health records. Two key features of such data are that incident disease is interval-censored between irregular visits and there can be pre-existing (prevalent) disease. Because prevalent disease is not always immediately diagnosed, some disease diagnosed at later visits are actually undiagnosed prevalent disease. We consider prevalent disease as a point mass at time zero for clinical applications where there is no interest in time of prevalent disease onset. We demonstrate that the naive Kaplan-Meier cumulative risk estimator underestimates risks at early time points and overestimates later risks. We propose a general family of mixture models for undiagnosed prevalent disease and interval-censored incident disease that we call prevalence-incidence models. Parameters for parametric prevalence-incidence models, such as the logistic regression and Weibull survival (logistic-Weibull) model, are estimated by direct likelihood maximization or by EM algorithm. Non-parametric methods are proposed to calculate cumulative risks for cases without covariates. We compare naive Kaplan-Meier, logistic-Weibull, and non-parametric estimates of cumulative risk in the cervical cancer screening program at Kaiser Permanente Northern California. Kaplan-Meier provided poor estimates while the logistic-Weibull model was a close fit to the non-parametric. Our findings support our use of logistic-Weibull models to develop the risk estimates that underlie current US risk-based cervical cancer screening guidelines. Published 2017. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Why does cervical cancer occur in a state-of-the-art screening program?

BACKGROUND: The goal of cervical screening is to detect and treat precancers before some become cancer. We wanted to understand why, despite state-of-the-art methods, cervical cancers occured in relationship to programmatic performance at Kaiser Permanente Northern California (KPNC), where >1,000,000 women aged ≥30years have undergone cervical cancer screening by triennial HPV and cytology cotesting since 2003. METHODS: We reviewed clinical histories preceding cervical cancer diagnoses to assign "causes" of cancer. We calculated surrogate measures of programmatic effectiveness (precancers/(precancers and cancers)) and diagnostic yield (precancers and cancers per 1000 cotests), overall and by age at cotest (30-39, 40-49, and ≥50years). RESULTS: Cancer was rare and found mainly in a localized (treatable) stage. Of 623 cervical cancers with at least one preceding or concurrent cotest, 360 (57.8%) were judged to be prevalent (diagnosed at a localized stage within one year or regional/distant stage within two years of the first cotest). Non-compliance with recommended screening and management preceded 9.0% of all cancers. False-negative cotests/sampling errors (HPV and cytology negative), false-negative histologic diagnoses, and treatment failures preceded 11.2%, 9.0%, and 4.3%, respectively, of all cancers. There was significant heterogeneity in the causes of cancer by histologic category (p<0.001 for all; p=0.002 excluding prevalent cases). Programmatic effectiveness (95.3%) and diagnostic yield were greater for squamous cell versus adenocarcinoma histology (p<0.0001) and both decreased with older ages (ptrend<0.0001). CONCLUSIONS: A state-of-the-art intensive screening program results in very few cervical cancers, most of which are detected early by screening. Screening may become less efficient at older ages.

Assessment of a New Lower-Cost Real-Time PCR Assay for Detection of High-Risk Human Papillomavirus: Useful for Cervical Screening in Limited-Resource Settings?

Inexpensive and easy-to-perform human papillomavirus (HPV) tests are needed for primary cervical cancer screening in lower-resource regions. In a convenience sample of 516 residual exfoliative cervical specimens from the Kaiser Permanente Northern California and U.S. National Cancer Institute Persistence and Progression Study, we assessed the agreement and clinical performance of a simple, inexpensive real-time PCR assay for the detection of 13 carcinogenic HPV types (the H13 assay; Hybribio, Hong Kong) that is marketed in limited-resource settings compared to previous testing by the Hybrid Capture 2 assay (HC2; Qiagen, Germantown, MD) and the Onclarity assay (BD Diagnostics, Sparks, MD). The test set was chosen to include many HPV-positive specimens. The reference standard was a combination of HC2 and Onclarity results for HPV detection and histologic diagnosis of controls (less than cervical intraepithelial neoplasia grade 2 [

Serum Fibrosis Marker Panels FIB-4 Index and Aspartate Aminotransferase (AST)-to-Platelet Ratio Index (APRI) Are Equivalent to AST Alone at Predicting Liver Fibrosis in a Cohort of 1731 Patients Infected with Hepatitis C Virus.

BACKGROUND: Efficient tools are needed to stage liver disease before treatment of patients infected with hepatitis C virus (HCV). Compared to biopsy, several studies demonstrated favorable performance of noninvasive multianalyte serum fibrosis marker panels [fibrosis-4 (FIB-4) index] and aspartate aminotransferase (AST)-to-platelet ratio index (APRI), but suggested cutoffs vary widely. Our objective was to evaluate FIB-4 index and APRI and their component tests for staging fibrosis in our HCV-infected population and to determine practical cutoffs to help triage an influx of patients requiring treatment. METHODS: Transient elastography (TE) results from 1731 HCV-infected patients were mapped to an F0-F4 equivalent scale. Each patient's APRI and FIB-4 index were calculated. Areas under the receiver operator curve (AUROCs) and false-positive and false-negative rates were calculated to retrospectively compare the performance of the indices and their component tests. RESULTS: The highest AUROCs for distinguishing severe (F3-F4) from mild-to-moderate (F0-F2) fibrosis had overlapping 95% CIs: APRI (0.77; 0.74-0.79), FIB-4 index (0.76; 0.73-0.78), and AST (0.74; 0.72-0.77). Cutoffs had false-negative rates of 2.7%-2.8% and false-positive rates of 6.4%-7.4% for all 3 markers. CONCLUSIONS: AST was as effective as FIB-4 index and APRI at predicting fibrosis. Published cutoffs for APRI and FIB-4 index would have been inappropriate in our population, with false-negative rates as high as 11%. For our purposes, no serum fibrosis marker was sufficiently sensitive to rule-out significant fibrosis, but cutoffs developed for AST, FIB-4 index, and APRI all had specificities of 79.2%-80.3% for ruling-in severe fibrosis and could be used to triage 1/3 of our population for treatment without waiting for TE or liver biopsy.

The population impact of human papillomavirus/cytology cervical cotesting at 3-year intervals: Reduced cervical cancer risk and decreased yield of precancer per screen.

BACKGROUND: The objective of cervical screening is to detect and treat precancer to prevent cervical cancer mortality and morbidity while minimizing overtreatment of benign human papillomavirus (HPV) infections and related minor abnormalities. HPV/cytology cotesting at extended 5-year intervals currently is a recommended screening strategy in the United States, but the interval extension is controversial. In the current study, the authors examined the impact of a decade of an alternative, 3-year cotesting, on rates of precancer and cancer at Kaiser Permanente Northern California. The effect on screening efficiency, defined as numbers of cotests/colposcopy visits needed to detect a precancer, also was considered. METHODS: Two cohorts were defined. The "open cohort" included all women screened at least once during the study period; > 1 million cotests were performed. In a fixed "long-term screening cohort," the authors considered the cumulative impact of repeated screening at 3-year intervals by restricting the cohort to women first cotested in 2003 through 2004 (ie, no women entering screening later were added to this group). RESULTS: Detection of cervical intraepithelial neoplasia 3/adenocarcinoma in situ (CIN3/AIS) increased in the open cohort (2004-2006: 82.0/100,000 women screened; 2007-2009: 140.6/100,000 women screened; and 2010-2012: 126.0/100,000 women screened); cancer diagnoses were unchanged. In the long-term screening cohort, the detection of CIN3/AIS increased and then decreased to the original level (2004-2006: 80.5/100,000 women screened; 2007-2009: 118.6/100,000 women screened; and 2010-2012: 84.9./100,000 women screened). The number of cancer diagnoses was found to decrease. When viewed in terms of screening efficiency, the number of colposcopies performed to detect a single case of CIN3/AIS increased in the cohort with repeat screening. CONCLUSIONS: Repeated cotesting at a 3-year interval eventually lowers population rates of precancer and cancer. However, a greater number of colposcopies are required to detect a single precancer. Cancer 2016;122:3682-6. © 2016 American Cancer Society.

A cohort study of cervical screening using partial HPV typing and cytology triage.

HPV testing is more sensitive than cytology for cervical screening. However, to incorporate HPV tests into screening, risk-stratification ("triage") of HPV-positive women is needed to avoid excessive colposcopy and overtreatment. We prospectively evaluated combinations of partial HPV typing (Onclarity, BD) and cytology triage, and explored whether management could be simplified, based on grouping combinations yielding similar 3-year or 18-month CIN3+ risks. We typed ∼9,000 archived specimens, taken at enrollment (2007-2011) into the NCI-Kaiser Permanente Northern California (KPNC) HPV Persistence and Progression (PaP) cohort. Stratified sampling, with reweighting in the statistical analysis, permitted risk estimation of HPV/cytology combinations for the 700,000+-woman KPNC screening population. Based on 3-year CIN3+ risks, Onclarity results could be combined into five groups (HPV16, else HPV18/45, else HPV31/33/58/52, else HPV51/35/39/68/56/66/68, else HPV negative); cytology results fell into three risk groups ("high-grade," ASC-US/LSIL, NILM). For the resultant 15 HPV group-cytology combinations, 3-year CIN3+ risks ranged 1,000-fold from 60.6% to 0.06%. To guide management, we compared the risks to established "benchmark" risk/management thresholds in this same population (e.g., LSIL predicted 3-year CIN3+ risk of 5.8% in the screening population, providing the benchmark for colposcopic referral). By benchmarking to 3-year risk thresholds (supplemented by 18-month estimates), the widely varying risk strata could be condensed into four action bands (very high risk of CIN3+ mandating consideration of cone biopsy if colposcopy did not find precancer; moderate risk justifying colposcopy; low risk managed by intensified follow-up to permit HPV "clearance"; and very low risk permitting routine screening.) Overall, the results support primary HPV testing, with management of HPV-positive women using partial HPV typing and cytology.

A joint model of persistent human papillomavirus infection and cervical cancer risk: Implications for cervical cancer screening.

New cervical cancer screening guidelines in the US and many European countries recommend that women get tested for human papillomavirus (HPV). To inform decisions about screening intervals, we calculate the increase in precancer/cancer risk per year of continued HPV infection. However, both time to onset of precancer/cancer and time to HPV clearance are interval-censored, and onset of precancer/cancer strongly informatively censors HPV clearance. We analyze this bivariate informatively interval-censored data by developing a novel joint model for time to clearance of HPV and time to precancer/cancer using shared random-effects, where the estimated mean duration of each woman's HPV infection is a covariate in the submodel for time to precancer/cancer. The model was fit to data on 9,553 HPV-positive/Pap-negative women undergoing cervical cancer screening at Kaiser Permanente Northern California, data that were pivotal to the development of US screening guidelines. We compare the implications for screening intervals of this joint model to those from population-average marginal models of precancer/cancer risk. In particular, after 2 years the marginal population-average precancer/cancer risk was 5%, suggesting a 2-year interval to control population-average risk at 5%. In contrast, the joint model reveals that almost all women exceeding 5% individual risk in 2 years also exceeded 5% in 1 year, suggesting that a 1-year interval is better to control individual risk at 5%. The example suggests that sophisticated risk models capable of predicting individual risk may have different implications than population-average risk models that are currently used for informing medical guideline development.