Human papillomavirus-based screening at extended intervals missed fewer cervical precancers than cytology in the HPV For Cervical Cancer (HPV FOCAL) trial.

While cervix screening using cytology is recommended at 2- to 3-year intervals, given the increased sensitivity of human papillomavirus (HPV)-based screening to detect precancer, HPV-based screening is recommended every 4- to 5-years. As organized cervix screening programs transition from cytology to HPV-based screening with extended intervals, there is some concern that cancers will be missed between screens. Participants in HPV FOr CervicAL Cancer (HPV FOCAL) trial received cytology (Cytology Arm) at 24-month intervals or HPV-based screening (HPV Arm) at 48-month intervals; both arms received co-testing (cytology and HPV testing) at exit. We investigated the results of the co-test to identify participants with cervical intraepithelial neoplasia grade 2 or higher (CIN2+) who would not have had their precancer detected if they had only their arm's respective primary screen. In the Cytology Arm, 25/62 (40.3%) identified CIN2+s were missed by primary screen (ie, normal cytology/positive HPV test) and all 25 had normal cytology at the prior 24-month screen. In the HPV arm, three CIN2+s (3/49, 6.1%) were missed by primary screen (ie, negative HPV test/abnormal cytology). One of these three misses had low-grade cytology findings and would also not have been referred to colposcopy outside of the trial. Multiple rounds of cytology did not detect some precancerous lesions detected with one round of HPV-based screening. In our population, cytology missed more CIN2+, even at shorter screening intervals, than HPV-based screening. This assuages concerns about missed detection postimplementation of an extended interval HPV-based screening program. We recommend that policymakers consider a shift from cytology to HPV-based cervix screening.

Long-term cervical precancer outcomes after a negative DNA- or RNA-based human papillomavirus test result.

BACKGROUND: Cervical cancer, a preventable disease associated with the human papillomavirus, is responsible for significant morbidity and mortality globally. Primary human papillomavirus testing is more sensitive in detecting precancerous cervical lesions than cytologic screening and can be conducted using either DNA- or RNA-based assays. Screening programs must select the most appropriate assay from several available assays for their population. It is not yet known whether these assays perform equivalently in the long term, particularly among women with a negative human papillomavirus test result. This study aims to compare long-term safety after a negative human papillomavirus test result across both DNA- and RNA-based testing assays. OBJECTIVE: This study aimed to compare long-term high-grade cervical intraepithelial neoplasia (grade 2 or higher and grade 3 or higher) outcomes of 2 DNA-based assays (Digene Hybrid Capture 2 High-Risk HPV DNA Test and cobas 4800 HPV Test) and 1 messenger RNA-based assay (Aptima HPV Assay) using data from the Human Papillomavirus For Cervical Cancer Trial-DECADEl (FOCAL-DECADE) cohort, by first comparing the positive and negative rates between the assays and then investigating the cumulative incidence of cervical intraepithelial neoplasia grade 2 and higher and grade 3 or higher detection among participants in the FOCAL DECADE cohort over follow-up according to human papillomavirus testing assays. STUDY DESIGN: The FOCAL Trial was a randomized controlled trial that evaluated human papillomavirus testing for primary cervical cancer screening. The FOCAL-DECADE cohort subsequently followed FOCAL Trial participants passively through the British Columbia Cervix Screening Program Database for approximately 10 years after the FOCAL Trial study exit to examine the rates of cervical intraepithelial neoplasia grade 2 or higher and grade 3 or higher. For this study, eligible participants had baseline human papillomavirus-negative results from at least 1 assay and had 1 or more cytologic screens after baseline (9509 participants for DNA-based and 3473 participants for DNA- vs RNA-based assay comparisons). We constructed cumulative incidence curves and compared the hazard ratios for cervical intraepithelial neoplasia grade 2 or higher and grade 3 or higher detection according to the assays. RESULTS: Over 10 years of follow-up, the cumulative incidence of cervical intraepithelial neoplasia grade 2 or higher and grade 3 or higher did not significantly differ between the DNA-based assays (hazard ratio, 0.95; 95% confidence interval, 0.84-1.06; P=.35 and hazard ratio, 0.82; 95% confidence interval, 0.66-1.01; P=.06 for cervical intraepithelial neoplasia grade 2 or higher and cervical intraepithelial neoplasia grade 3 or higher, respectively) or between the DNA- and RNA-based assays (hazard ratio, 0.97; 95% confidence interval, 0.87-1.06; P=.48 and hazard ratio, 0.94; 95% confidence interval, 0.79-1.13; P=.52 for cervical intraepithelial neoplasia grade 2 or higher and cervical intraepithelial neoplasia grade 3 or higher, respectively). CONCLUSION: Among participants who tested negative for human papillomavirus at baseline, the long-term risk of cervical intraepithelial neoplasia grade 2 or higher and grade 3 or higher did not significantly differ regardless of whether DNA- or RNA-based human papillomavirus testing assays were used. Screening program decision makers can be confident that for women who test negative for human papillomavirus, DNA- and RNA-based assays exhibit similar cervical intraepithelial neoplasia grade 2 or higher outcomes over several years.

Immunogenicity of 2 and 3 Doses of the Quadrivalent Human Papillomavirus Vaccine up to 120 Months Postvaccination: Follow-up of a Randomized Clinical Trial.

BACKGROUND: Several countries have implemented a 2-dose (2D) human papillomavirus (HPV) vaccination schedule for adolescents based on immunobridging studies. We compared immunogenicity of 2D vs 3-dose (3D) schedules of the quadrivalent vaccine (4vHPV) up to 10 years after the first dose. METHODS: Girls aged 9-13 years were randomized to receive 2D or 3D and were compared with women aged 16-26 receiving 3D at day 1 and months 7, 24, and 120 after the first dose. Antibody levels for HPV6/11/16/18 were evaluated using the competitive Luminex immunoassay (cLIA) and total immunoglobulin G assay. Geometric mean titers (GMTs) and seropositivity rates were compared between the different groups at different time points. Noninferiority of GMT ratios was defined as the lower bound of the 2-sided 95% confidence interval (CI) being greater than 0.5. Kinetics of antibody titers over time among study groups were examined. RESULTS: At 120 months, data from 35 2D girls, 38 3D girls, and 30 3D women were used for analyses. cLIA seropositivity rates were above 95% for all HPV vaccine types and all schedules, except HPV18, with the lowest seropositivity observed among 3D women (60.0%; 95% CI, 40.6%-77.3%). GMT ratios (cLIA) for both 2D and 3D girls were noninferior to 3 doses in women for HPV6/11/16/18. Trends were comparable between assays. CONCLUSIONS: GMTs for HPV6/11/16/18 after 2D or 3D of 4vHPV in girls were noninferior to 3D in adult women up to 120 months postvaccination. This study demonstrates long-term immunogenicity of the 2D HPV vaccine schedule.

Disease detection at the 48-month exit round of the HPV FOCAL cervical cancer screening trial in women per-protocol eligible for routine screening.

HPV FOCAL is a randomized control trial of cervical cancer screening. The intervention arm received baseline screening for high-risk human papillomavirus (HPV) and the control arm received liquid-based cytology (LBC) at baseline and 24 months. Both arms received 48-month exit HPV and LBC cotesting. Exit results are presented for per-protocol eligible (PPE) screened women. Participants were PPE at exit if they had completed all screening and recommended follow-up and had not been diagnosed with cervical intraepithelial neoplasia Grade 2 or worse (CIN2+) earlier in the trial. Subgroups were identified based upon results at earlier trial screening. There were 9,457 and 9,552 and women aged 25-65 randomized to control and intervention and 7,448 (77.8%) and 8,281 (86.7%), respectively, were PPE and screened. Exit cotest results were similar (p = 0.11) by arm for PPE and the relative rate (RR) of CIN2+ for intervention vs. control was RR = 0.83 (95% CI: 0.56-1.23). The RR for CIN2+ comparing intervention women baseline HPV negative to control women with negative cytology at baseline and at 24 months, was 0.68 (95% CI: 0.43-1.06). PPE women who had a negative or CIN1 colposcopy in earlier rounds had elevated rates (per 1,000) of CIN2+ at exit, control 31 (95% CI: 14-65) and intervention 43 (95% CI: 25-73). Among PPE women HPV negative at exit LBC cotesting identified little CIN2+, Rate = 0.3 (95% CI: 0.1-0.7). This per-protocol analysis found that screening with HPV using a 4-year interval is as safe as LBC with a 2-year screening interval. LBC screening in HPV negative women at exit identified few additional lesions.

Loss to follow-up: A significant barrier in the treatment cascade with direct-acting therapies.

Effectiveness of direct-acting antiviral (DAA) therapies could be influenced by patient characteristics such as comorbid conditions, which could lead to premature treatment discontinuation and/or irregular medical follow-ups. Here, we evaluate loss to follow-up and treatment effectiveness of sofosbuvir/ledipasvir ± ribavirin (SOF/LDV ± RBV), ombitasvir/paritaprevir/ritonavir + dasabuvir ± ribavirin (OBV/PTV/r + DSV ± RBV) for hepatitis C virus (HCV) genotype 1 (GT1) and sofosbuvir + ribavirin (SOF + RBV) for genotype 3 (GT3) in British Columbia Canada: The British Columbia Hepatitis Testers Cohort includes data on individuals tested for HCV since 1992, integrated with medical visit, hospitalization and prescription drug data. HCV-positive individuals who initiated DAA regimens, irrespective of treatment completion, for GT1 and GT3 until 31 December, 2017 were included. Factors associated with sustained virological response (SVR) and loss to follow-up were assessed by using multivariable logistic regression models. In total 4477 individuals initiated DAAs. The most common prescribed DAA was SOF/LDV ± RBV with SVR of 95%. The highest SVR of 99.5% was observed among OBV/PTV/r + DSV-treated patients. Overall, 453 (10.1%) individuals were lost to follow-up. Higher loss to follow-up was observed among GT1 patients treated with OBV (17.8%) and GT3 patients (15.7%). The loss to follow-up rate was significantly higher among individuals aged <60 years, those with a history of injection drug use (IDU), on opioid substitution therapy and with cirrhosis. Our findings indicate that loss to follow-up exceeds viral failure in HCV DAA therapy and its rate varies significantly by genotype and treatment regimen. Depending on the aetiology of lost to follow-up, personalized case management for those with medical complications and supporting services among IDU are needed to achieve the full benefits of effective treatments.

Evaluation of a validated methylation triage signature for human papillomavirus positive women in the HPV FOCAL cervical cancer screening trial.

Human papillomavirus (HPV)-based cervical cancer screening requires triage of HPV positive women to identify those at risk of cervical intraepithelial neoplasia grade 2 (CIN2) or worse. We conducted a blinded case-control study within the HPV FOCAL randomized cervical cancer screening trial of women aged 25-65 to examine whether baseline methylation testing using the S5 classifier provided triage performance similar to an algorithm relying on cytology and HPV genotyping. Groups were randomly selected from women with known HPV/cytology results and pathology outcomes. Group 1: 104 HPV positive (HPV+), abnormal cytology (54 CIN2/3; 50

Estimating the impact of early hepatitis C virus clearance on hepatocellular carcinoma risk.

Although achieving sustained virological response (SVR) through antiviral therapy could reduce the risk of hepatocellular carcinoma (HCC) attributable to hepatitis C virus (HCV) infection, the impact of early viral clearance on HCC is not well defined. In this study, we compared the risk of HCC among individuals who spontaneously cleared HCV (SC), the referent population, with the risk in untreated chronic HCV (UCHC), those achieved SVR, and those who failed interferon-based treatment (TF). The BC Hepatitis Testers Cohort (BC-HTC) includes individuals tested for HCV between 1990-2013, integrated with medical visits, hospitalizations, cancers, prescription drugs and mortality data. This analysis included all HCV-positive patients with at least one valid HCV RNA by PCR on or after HCV diagnosis. Of 46 666 HCV-infected individuals, there were 12 527 (26.8%) SC; 24 794 (53.1%) UCHC; 5355 (11.5%) SVR and 3990 (8.5%) TF. HCC incidence was lowest (0.3/1000 person-years (PY)) in the SC group and highest in the TF group (7.7/1000 PY). In a multivariable model, compared to SC, TF had the highest HCC risk (hazard ratio (HR):14.52, 95% confidence interval (CI): 9.83-21.47), followed by UCHC (HR: 5.85; 95% CI: 4.07-8.41). Earlier treatment-based viral clearance similar to SC could decrease HCC incidence by 69.4% (95% CI: 57.5-78.0), 30% (95% CI: 10.8-45.1) and 77.5% (95% CI: 69.4-83.5) among UCHC, SVR and TF patients, respectively. In conclusion, using SC as a real-world comparator group, it showed that substantial reduction in HCC risk could be achieved with earlier treatment initiation. These analyses should be replicated in patients who have been treated with direct acting antiviral therapies.

Effect of Screening With Primary Cervical HPV Testing vs Cytology Testing on High-grade Cervical Intraepithelial Neoplasia at 48 Months: The HPV FOCAL Randomized Clinical Trial.

Importance: There is limited information about the relative effectiveness of cervical cancer screening with primary human papillomavirus (HPV) testing alone compared with cytology in North American populations. Objective: To evaluate histologically confirmed cumulative incident cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) detected up to and including 48 months by primary HPV testing alone (intervention) or liquid-based cytology (control). Design, Setting, and Participants: Randomized clinical trial conducted in an organized Cervical Cancer Screening Program in Canada. Participants were recruited through 224 collaborating clinicians from January 2008 to May 2012, with follow-up through December 2016. Women aged 25 to 65 years with no history of CIN2+ in the past 5 years, no history of invasive cervical cancer, or no history of hysterectomy; who have not received a Papanicolaou test within the past 12 months; and who were not receiving immunosuppressive therapy were eligible. Interventions: A total of 19 009 women were randomized to the intervention (n = 9552) and control (n = 9457) groups. Women in the intervention group received HPV testing; those whose results were negative returned at 48 months. Women in the control group received liquid-based cytology (LBC) testing; those whose results were negative returned at 24 months for LBC. Women in the control group who were negative at 24 months returned at 48 months. At 48-month exit, both groups received HPV and LBC co-testing. Main Outcomes and Measures: The primary outcome was the cumulative incidence of CIN3+ 48 months following randomization. The cumulative incidence of CIN2+ was a secondary outcome. Results: Among 19 009 women who were randomized (mean age, 45 years [10th-90th percentile, 30-59]), 16 374 (8296 [86.9%] in the intervention group and 8078 [85.4%] in the control group) completed the study. At 48 months, significantly fewer CIN3+ and CIN2+ were detected in the intervention vs control group. The CIN3+ incidence rate was 2.3/1000 (95% CI, 1.5-3.5) in the intervention group and 5.5/1000 (95% CI, 4.2-7.2) in the control group. The CIN3+ risk ratio was 0.42 (95% CI, 0.25-0.69). The CIN2+ incidence rate at 48 months was 5.0/1000 (95% CI, 3.8-6.7) in the intervention group and 10.6/1000 (95% CI, 8.7-12.9) in the control group. The CIN2+ risk ratio was 0.47 (95% CI, 0.34-0.67). Baseline HPV-negative women had a significantly lower cumulative incidence of CIN3+ at 48 months than cytology-negative women (CIN3+ incidence rate, 1.4/1000 [95% CI, 0.8-2.4]; CIN3+ risk ratio, 0.25 [95% CI, 0.13-0.48]). Conclusions and Relevance: Among women undergoing cervical cancer screening, the use of primary HPV testing compared with cytology testing resulted in a significantly lower likelihood of CIN3+ at 48 months. Further research is needed to understand long-term clinical outcomes as well as cost-effectiveness. Trial Registration: isrctn.org Identifier: ISRCTN79347302.

HPV for cervical cancer screening (HPV FOCAL): Complete Round 1 results of a randomized trial comparing HPV-based primary screening to liquid-based cytology for cervical cancer.

Complete Round 1 data (baseline and 12-month follow-up) for HPV FOCAL, a randomized trial establishing the efficacy of HPV DNA testing with cytology triage as a primary screen for cervical cancer are presented. Women were randomized to one of three arms: Control arm - Baseline liquid-based cytology (LBC) with ASCUS results triaged with HPV testing; Intervention and Safety arms - Baseline HPV with LBC triage for HPV positives. Results are presented for 15,744 women allocated to the HPV (intervention and safety combined) and 9,408 to the control arms. For all age cohorts, the CIN3+ detection rate was higher in the HPV (7.5/1,000; 95%CI: 6.2, 8.9) compared to the control arm (4.6/1,000; 95%CI: 3.4, 6.2). The CIN2+ detection rates were also significantly higher in the HPV (16.5/1,000; 95%CI: 14.6, 18.6) vs. the control arm (10.1/1,000; 95%CI: 8.3, 12.4). In women ≥35 years, the overall detection rates for CIN2+ and CIN3+ were higher in the HPV vs. the control arm (CIN2+:10.0/1,000 vs. 5.2/1,000; CIN3+: 4.2/1,000 vs. 2.2/1,000 respectively, with a statistically significant difference for CIN2+). HPV testing detected significantly more CIN2+ in women 25-29 compared to LBC (63.7/1,000; 95%CI: 51.9, 78.0 vs. 32.4/1,000; 95%CI: 22.3, 46.8). HPV testing resulted in significantly higher colposcopy referral rates for all age cohorts (HPV: 58.9/1,000; 95%CI: 55.4, 62.7 vs. CONTROL: 30.9/1,000; 95%CI: 27.6, 34.6). At completion of Round 1 HPV-based cervical cancer screening in a population-based program resulted in greater CIN2+ detection of across all age cohorts compared to LBC screening.

Long-term effect of sustained virological response on hepatocellular carcinoma in patients with hepatitis C in Canada.

BACKGROUND & AIMS: Evidence is limited on hepatocellular carcinoma (HCC) risk after sustained virological response (SVR) to interferon-based treatment of hepatitis C virus (HCV) infection. We evaluated the effect of SVR on the risk of HCC and estimated its incidence in post-SVR HCV patients from a large population-based Canadian cohort. METHODS: The British Columbia Hepatitis Testers Cohort includes individuals tested for HCV between 1990-2013 linked with data on their medical visits, hospitalizations, cancers, prescription drugs and mortality. Patients receiving interferon-based HCV treatments were followed from the end of treatment to HCC diagnosis, death or December 31, 2012. We examined HCC risk among those who did and did not achieve SVR using multivariable proportional hazard models with the Fine and Gray modification for competing risks. RESULTS: Of 8147 individuals who received HCV treatment and were eligible for analysis, 4663 (57%) achieved SVR and 3484 (43%) did not. Each group was followed for a median of 5.6years (range: 0.5-12.9) for an HCC incidence rate of 1.1/1000 person-years (PY) among the SVR and 7.2/1000 PY among the no SVR group. The HCC incidence rate was higher among those with cirrhosis (SVR: 6.4, no SVR: 21.0/1000 PY). In the multivariable model, SVR was associated with a lower HCC risk (subdistribution hazard ratio [SHR]=0.20, 95% CI: 0.13-0.3), while cirrhosis (SHR=2.61, 95% CI: 1.68-4.04), age ⩾50years, being male and genotype 3 infection were associated with a higher HCC risk. Among those who achieved SVR, cirrhosis, age ⩾50years and being male were associated with a higher HCC risk. CONCLUSION: SVR after interferon-based treatment substantially reduces but does not eliminate HCC risk, which is markedly higher among those with cirrhosis and age ⩾50years at treatment initiation. Treatment of patients at an advanced fibrosis stage with new highly effective drugs will warrant continued surveillance for HCC post-SVR. LAY SUMMARY: We assessed the effect of successful hepatitis C treatment with older interferon-based treatment on the occurrence of liver cancer (hepatocellular carcinoma) and found that successful treatment prevents liver cancer. However, more people with cirrhosis and older age continued to develop liver cancer after successful treatment. Thus, treatment with new drugs among those with cirrhosis will require continued monitoring for liver cancer.

Post-Loop Electrosurgical Excision Procedure High-Risk Human Papillomavirus Testing as a Test of Cure: The British Columbia Experience.

OBJECTIVES: To determine whether Hybrid Capture 2 High-Risk HPV DNA Test (HC2) can be used as a test of cure in women treated for cervical intraepithelial neoplasia grade 2 or worse (CIN 2+) and allow discharge from colposcopy follow-up with a return to a cytology-based screening program for HC2-negative women. MATERIALS AND METHODS: Data were analyzed for all women who underwent a loop electrosurgical excision procedure between August 1, 2008, and June 30, 2011, and had a valid HC2 result after loop electrosurgical excision procedure and follow-up histopathology result, to determine risk of persistent or recurrent CIN 2+ in HC2-positive and HC2-negative women. RESULTS: Two thousand three hundred forty women had adequate biopsies and valid HC2 results. Of 460 HC2-positive women, 118 (25.7%) were diagnosed with CIN 2+, whereas of 1,880 HC2-negative women, 35 (1.9%) had a subsequent diagnosis of CIN 2+ (p < .0002) yielding a HC2-negative predictive value of 98.1% (95% confidence interval = 97.4-98.7). Of 460 HC2-positive women, 306 initially had negative biopsies. In the subsequent 36 months, 38 of the 306 were diagnosed with CIN 2+. CONCLUSIONS: We conclude that women with a negative HC2 test can safely return to routine annual cytology screening by primary care providers while women who test HC2 positive are at higher risk and should continue to be followed by colposcopy, even if their initial biopsy is negative.

Disease detection and resource use in the safety and control arms of the HPV FOCAL cervical cancer screening trial.

BACKGROUND: The HPV FOCAL Trial is a RCT comparing human papilloma virus (HPV) with Liquid Based Cytology (LBC) screening for cervical cancer. Results are presented for the comparison of the Safety and Control arms after two rounds. METHODS: HPV FOCAL included randomisation of women aged 25-65 into the Safety arm, where they were initially screened with HPV and the Control arm, where they received entry screening with LBC, with both arms screened again with LBC at 24 months. RESULTS: There are 6203 (Safety) and 6075 (Control) women included in this analysis. For the Safety vs Control arms, Round 1 screening resulted in increased detection of cervical intraepithelial neoplasia 2 or worse (CIN2+),15.3 vs 10.4 per 1000, RR=1.48 (95%CI=1.08-2.03) and higher colposcopy referral rates, 5.6% vs 3.2%. LBC screening at 24 months resulted in similar colposcopy referral rates, 1.5% vs 1.9%, and decreased CIN2+ detection, 2.0 vs 4.7 per 1000, RR=0.43 (95%CI=0.21-0.88) in the Safety vs Control arms. CIN2+ detection and colposcopy referral rates declined with increasing age in both arms. One round of HPV screening detected similar levels of CIN2+ as two rounds of LBC screening. INTERPRETATION: CIN2+ detection at 2 years was lower in those screened by HPV, indicating an improved 2-year negative predictive value of the HPV test.

Differentiation of acute from chronic hepatitis C virus infection by nonstructural 5B deep sequencing: a population-level tool for incidence estimation.

UNLABELLED: The ability to classify acute versus chronic hepatitis C virus (HCV) infections at the time of diagnosis is desirable to improve the quality of surveillance information. The aim of this study was to differentiate acute from chronic HCV infections utilizing deep sequencing. HCV nonstructural 5B (NS5B) amplicons (n = 94) were generated from 77 individuals (13 acute and 64 chronic HCV infections) in British Columbia, Canada, with documented seroconversion time frames. Amplicons were deep sequenced and HCV genomic diversity was measured by Shannon entropy (SE) and a single nucleotide variant (SNV) analysis. The relationship between each diversity measure and the estimated days since infection was assessed using linear mixed models, and the ability of each diversity measure to differentiate acute from chronic infections was assessed using generalized estimating equations. Both SE and the SNV diversity measures were significantly different for acute versus chronic infections (P < 0.009). NS5B nucleotide diversity continued to increase for at least 3 years postinfection. Among individuals with the least uncertainty with regard to duration of infection (n = 39), the area under the receiver operating characteristic curve (AUROC) was high (0.96 for SE; 0.98 for SNV). Although the AUROCs were lower (0.86 for SE; 0.80 for SNV) when data for all individuals were included, they remain sufficiently high for epidemiological purposes. Synonymous mutations were the primary discriminatory variable accounting for over 78% of the measured genetic diversity. CONCLUSIONS: NS5B sequence diversity assessed by deep sequencing can differentiate acute from chronic HCV infections and, with further validation, could become a powerful population-level surveillance tool for incidence estimation.

Twin epidemics of new and prevalent hepatitis C infections in Canada: BC Hepatitis Testers Cohort.

BACKGROUND: We characterized the twin epidemics of new and prevalent hepatitis C virus (HCV) infections in British Columbia, Canada to inform prevention, care and treatment programs. METHODS: The BC Hepatitis Testers Cohort (BC-HTC) includes individuals tested for HCV, HIV or reported as a case of HBV, HCV, HIV or active TB between 1990-2013 linked with data on their medical visits, hospitalizations, cancers, prescription drugs and mortality. Prevalent infection was defined as being anti-HCV positive at first test. Those with a negative test followed by a positive test were considered seroconverters or new infections. RESULTS: Of 1,132,855 individuals tested for HCV, 64,634 (5.8 %) were positive and an additional 3092 cases tested positive elsewhere for a total of 67,726. Of 55,781 HCV positive individuals alive at the end of 2013, 7064 were seroconverters while 48,717 had prevalent infection at diagnosis. The HCV positivity rate (11.2 %) was highest in birth cohort 1945-1964 which declined over time. New infections were more likely to be male, 15-34 years of age (born 1965-1984), HIV- or HBV-coinfected, socioeconomically disadvantaged, have problematic drug and alcohol use and a mental health illness. The profile was similar for individuals with prevalent infection, except for lower odds of HBV-coinfection, major mental health diagnoses and birth cohort >1975. CONCLUSIONS: The HCV positivity rate is highest in birth cohort 1945-1964 which represents most prevalent infections. New infections occur in younger birth cohorts who are commonly coinfected with HIV and/or HBV, socioeconomically marginalized, and living with mental illness and addictions.

Comparison of the Roche cobas® 4800 and Digene Hybrid Capture® 2 HPV tests for primary cervical cancer screening in the HPV FOCAL trial.

BACKGROUND: HPV FOCAL is a randomized trial (ISRCTN79347302, registered 20 Apr 2007) comparing high-risk (hr) HPV testing vs. liquid-based cytology (LBC) for cervical cancer screening of women aged 25-65. We compared the Digene Hybrid Capture® 2 High-Risk HPV DNA Test® (HC2) and the Roche cobas® 4800 HPV Test (COBAS) for primary screening. METHODS: Women (n=6,172) were screened at baseline by HC2 and COBAS and by LBC 24 months later. We assessed HPV genotyping and reflex LBC for colposcopy triage of baseline HPV positive women. RESULTS: Overall HC2/COBAS agreement was 96.1% (kappa 0.75) and positive agreement was 77.5%. Baseline CIN2 and CIN3+ rates based on HPV screening were 8.6/1,000 and 6.6/1,000 respectively; 24 month rates were 0.7/1,000 and 0.4/1,000 (LBC screening). HC2 and COBAS were concordant positive for 91% of round 1 CIN2 and 98% of CIN3+. CIN3+ was significantly associated with HPV 16 (Odds Ratio [OR] 5.11; 95% confidence interval [CI] 2.30, 11.37), but not HPV 18 (OR 2.62; 95% CI 0.73, 9.49), vs. non-HPV 16/18 HPV at baseline. There was no significant association between HPV genotype and CIN2. CIN3+ was significantly more likely for high-grade (OR 5.99; 95% CI 2.53, 14.18), but not low-grade (OR 0.54; 95% CI 0.20, 1.49), vs. negative LBC. No significant association was observed between LBC grade and CIN2. HPV 16 and 18 were associated with 33% of CIN2 and 68% of CIN3+ identified at baseline. CONCLUSIONS: For hrHPV positive women, abnormal reflex LBC is appropriate for colposcopy triage. In addition, immediate referral of women with HPV 16/18 and normal cytology may allow for earlier detection of CIN2+ lesions which would not be detected until after follow-up testing.

Projected Impact of HPV and LBC Primary Testing on Rates of Referral for Colposcopy in a Canadian Cervical Cancer Screening Program.

OBJECTIVE: To estimate the impact of implementing primary human papilloma virus liquid-based cytology (LBC) screening on four-year rates of referral for colposcopy in the British Columbia screening program. METHODS: We used data on referral for colposcopy from an RCT (HPV FOCAL) comparing HPV testing every four years with LBC testing every two years. We also used data from population screening with conventional cytology among women aged 25 to 69. The predicted effect of adoption of either trial protocol on rates of referral for colposcopy was estimated using trial age-specific result and screening result-specific rates weighted by their screening program distribution. The cumulative age-specific rates of referral for colposcopy over four years were calculated. RESULTS: Use of HPV testing initially increased rates of referral for colposcopy in the trial, but over four years the cumulative rates of referral were similar to those for LBC except in women aged 25 to 29, in whom a substantial excess persisted. Four-year rates of referral for colposcopy declined with age in women screened with HPV testing, LBC, and conventional cytology. Extrapolating the trial results to the distribution in the provincial screening program, implementation of either HPV or LBC throughout the provincial population would approximately double the current rates of referral for colposcopy. CONCLUSION: Compared with LBC screening, primary screening for HPV increased rates of referral for colposcopy only among women aged 25 to 29. In contrast to current practice, referral for colposcopy was largely driven by the trial protocol recommendations for the management of abnormal results and not by which screening test was used.

Objectif : Estimer les effets de la mise en œuvre d'un dépistage primaire du virus du papillome humain par cytologie en milieu liquide (CML) sur les taux d'orientation en colposcopie sur quatre ans, dans le cadre du programme de dépistage de la Colombie-Britannique. Méthodes : Nous avons utilisé les données sur l'orientation en colposcopie issues d'un ECR (HPV FOCAL) comparant le dépistage du VPH tous les quatre ans au dépistage par CML tous les deux ans. Nous avons également utilisé des données issues du dépistage populationnel par cytologie conventionnelle mené auprès des femmes de 25 à 69 ans. Le taux d'orientation en colposcopie en fonction de l'âge et le taux d'orientation en colposcopie en fonction des résultats de dépistage ont été pondérés en fonction de la distribution de leurs programmes de dépistage respectifs, ce qui a permis d'estimer l'effet populationnel prévu de l'adoption de l'un ou l'autre des protocoles d'essai en question sur les taux d'orientation en colposcopie. Les taux cumulatifs (en fonction de l'âge) de l'orientation en colposcopie sur quatre ans ont été calculés. Résultats : Le recours au dépistage du VPH a initialement mené à la hausse des taux d'orientation en colposcopie dans le cadre de l'essai; toutefois, sur quatre ans, les taux cumulatifs d'orientation ont été semblables à ceux de la CML, sauf chez les femmes de 25 à 29 ans (chez lesquelles un excès substantiel a persisté). Les taux d'orientation en colposcopie sur quatre ans ont connu une baisse en fonction de l'âge chez les femmes ayant fait l'objet d'un dépistage du VPH, d'une CML et d'une cytologie conventionnelle. En extrapolant les résultats de l'essai à la distribution qui existe au sein du programme provincial de dépistage, nous avons constaté que la mise en œuvre du dépistage du VPH ou de la CML au sein de la population provinciale mènerait au doublement approximatif des taux actuels d'orientation en colposcopie. Conclusion : Par comparaison avec le dépistage par CML, le dépistage primaire du VPH n'a entraîné la hausse des taux d'orientation en colposcopie que chez les femmes de 25 à 29 ans. Contrairement à la pratique actuelle, l'orientation en colposcopie était largement motivée par les recommandations du protocole d'essai en ce qui concerne la prise en charge des résultats anormaux, et non par le test de dépistage utilisé.

Evidence of Decreased Long-term Risk of Cervical Precancer after Negative Primary HPV Screens Compared with Negative Cytology Screens in a Longitudinal Cohort Study.

BACKGROUND: The growing use of primary human papillomavirus (HPV) cervical cancer screening requires determining appropriate screening intervals to avoid overtreatment of transient disease. This study examined the long-term risk of cervical precancer after HPV screening to inform screening interval recommendations. METHODS: This longitudinal cohort study (British Columbia, Canada, 2008 to 2022) recruited women and individuals with a cervix who received 1 to 2 negative HPV screens (HPV1 cohort, N = 5,546; HPV2 cohort, N = 6,624) during a randomized trial and women and individuals with a cervix with 1 to 2 normal cytology results (BCS1 cohort, N = 782,297; BCS2 cohort, N = 673,778) extracted from the provincial screening registry. All participants were followed through the registry for 14 years. Long-term risk of cervical precancer or worse [cervical intraepithelial neoplasia grade 2 or worse (CIN2+)] was compared between HPV and cytology cohorts. RESULTS: Cumulative risks of CIN2+ were 3.2/1,000 [95% confidence interval (CI), 1.6-4.7] in HPV1 and 2.7/1,000 (95% CI, 1.2-4.2) in HPV2 after 8 years. This was comparable with the risk in the cytology cohorts after 3 years [BCS1: 3.3/1,000 (95% CI, 3.1-3.4); BCS2: 2.5/1,000 (95% CI, 2.4-2.6)]. The cumulative risk of CIN2+ after 10 years was low in the HPV cohorts [HPV1: 4.7/1,000 (95% CI, 2.6-6.7); HPV2: 3.9 (95% CI, 1.1-6.6)]. CONCLUSIONS: Risk of CIN2+ 8 years after a negative screen in the HPV cohorts was comparable with risk after 3 years in the cytology cohorts (the benchmark for acceptable risk). IMPACT: These findings suggest that primary HPV screening intervals could be extended beyond the current 5-year recommendation, potentially reducing barriers to screening.

Mortality among British Columbians testing for hepatitis C antibody.

BACKGROUND: Hepatitis C virus (HCV) infection is a major preventable and treatable cause of morbidity and mortality. The ability to link population based centralized laboratory HCV testing data with administrative databases provided a unique opportunity to compare mortality between HCV seronegative and seropositive individuals. Through the use of laboratory testing patterns and results, the objective of this study was to differentiate the viral effects of mortality due to HCV infection from risk behaviours/activities that are associated with acquisition of HCV infection. METHODS: Serological testing data from the British Columbia (BC) Centre for Disease Control Public Health Microbiology and Reference Laboratory from 1992-2004 were linked to the BC Vital Statistics Agency death registry. Four groups of HCV testers were defined by their HCV antibody (anti-HCV) testing patterns: single non-reactive (SNR); serial multiple tested non-reactive (MNR); reactive at initial testing (REAC); and seroconverter (SERO) (previously seronegative followed by reactive, a marker for incident infection). Standardized mortality ratios (SMRs) were calculated to compare the relative risk of all cause and disease specific mortality to that of the BC population for each serological group. Time dependent Cox proportional hazard regression was used to compare hazard ratios (HRs) among HCV serological groups. RESULTS: All anti-HCV testers had higher SMRs than the BC population. Referent to the SNR group, the REAC group had higher risks for liver (HR: 9.62; 95% CI=8.55-10.87) and drug related mortality (HR: 13.70; 95% CI=11.76-16.13). Compared to the REAC group, the SERO group had a lower risk for liver (HR: 0.53; 95% CI=0.24-0.99), but a higher risk for drug related mortality (HR: 1.54; 95% CI=1.12-2.05). CONCLUSIONS: These findings confirm that individuals who test anti-HCV positive have increased mortality related to progressive liver disease, and that a substantial proportion of the mortality is attributable to drug use and risk behaviours/activities associated with HCV acquisition. Mortality reduction in HCV infected individuals will require comprehensive prevention programming to reduce the harms due to behaviours/activities which relate to HCV acquisition, as well as HCV treatment to prevent progression of chronic liver disease.

Genetic diversity as a marker for timing infection in HIV-infected patients: evaluation of a 6-month window and comparison with BED.

BACKGROUND: It has been reported that the increase in human immunodeficiency virus (HIV) sequence diversity in drug resistance surveillance specimens may be used to classify the duration of HIV infection as <1 or >1 year. We describe a mixed base classifier (MBC) optimized to categorize the duration of subtype B infections as <6 or >6 months on the basis of sequences for drug resistance surveillance specimens and compared MBC findings with those of serologic methods. METHODS: The behavior of the MBC was examined across a range of thresholds for calling mixed bases. MBC performance was then evaluated using either complete pol sequences or sites reflecting evolutionary pressures (HLA selection sites, sites that increased in entropy over the course of infection, and codon positions). RESULTS: The MBC performance was optimal when secondary peaks on the sequencing chromatogram accounted for at least 15% of the area of primary peaks. A cutoff of <0.45% mixed bases in the pol region best identified recent infections (sensitivity = 82.7%, specificity = 78.8%), with improvement achieved by analyzing only sites that increased in entropy. CONCLUSIONS: In an extended data set of 1354 specimens classified by BED, the optimized MBC performed significantly better than a simple MBC (agreement, 68.98% vs 67.13%). If further validated, the MBC may prove beneficial for detecting recent infection and estimating the incidence of HIV infection.

Colposcopy referral rates post-introduction of primary screening with human papillomavirus testing: evidence from a large British Columbia cohort study.

Background: Shifting from cytology to human papillomavirus (HPV)-based cervical cancer screening will initially increase colposcopy referrals. The anticipated impact on health systems has been raised as a concern for implementation. It is unclear if the higher rate of colposcopy referrals is sustained after initial HPV-based screens or reverts to new lower baselines due to earlier detection and treatment of precancer. This study aimed to investigate long-term rates of colposcopy referrals after participation in HPV-based screening. Methods: Participants of HPV for Cervical Cancer Screening trial (HPV FOCAL) received one (HPV1, N = 6204) or two (HPV2, N = 9540) HPV-based screens. After exit, they returned to British Columbia's (BC) cytology screening program. A comparison cohort from the BC screening population (BCS, N = 1,140,745) was identified, mirroring trial inclusion criteria. All participants were followed for 10-14 years through the provincial screening registry. Colposcopy referral rates per 1000 screens were calculated for each group. Trial colposcopy referrals for HPV1 and HPV2 were calculated under two referral scenarios: (1) all HPV positive referred to colposcopy; (2) cytology triage with ASCUS or greater referred to colposcopy. Colposcopy referrals from post-trial screens in HPV1 an HPV2 and all screens in BCS were based on actual recommendations from the screening program. A multivariable flexible survival regression model compared hazard ratios (HR) throughout follow-up. Findings: Scenario 2 referral rates were higher during initial HPV screen(s) vs cytology screen (HPV1: 28 per 1000 screens (95% CI: 24, 33), HPV2: 32 per 1000 screens (95% CI: 29, 36), BCS: 8 per 1000 screens (95% CI: 8.9)). However, post-trial rates in HPV1 and HPV2 were significantly lower than in BCS. Cumulative rates in HPV1 and HPV2 approached the cumulative rate in BCS 11-12 years after HPV-based screening (HPV1: 11 per 1000 screens (95% CI: 10, 12), HPV2: 16 per 1000 screens (95% CI: 15-17), BCS: 11 per 1000 screens (95% CI: 10, 11)). Adjusted models demonstrated reductions in referral rates in HPV1 (HR = 0.6, 95% CI: 0.5, 0.7) and HPV2 (HR = 0.7, 95% CI: 0.6, 0.8) relative to BCS by 54 and 72 months post-final HPV screen respectively. Interpretation: Reduced colposcopy referral rates were observed after initial rounds of HPV-based screening. After initial HPV screening, referral rates to colposcopy after cytology triage were below the current rates seen in a centralized cytology program after approximately four years. Any expected increase in referrals at initiation of HPV-based screening could be countered by staged program implementation. Funding: This work was supported by the National Institutes of Health (R01 CA221918), Michael Smith Health Research BC (RT-2021-1595), and the Canadian Institutes of Health Research (MCT82072).