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.

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.

Assessing 10-Year Safety of a Single Negative HPV Test for Cervical Cancer Screening: Evidence from FOCAL-DECADE Cohort.

BACKGROUND: Long-term safety of a single negative human papillomavirus (HPV) test for cervical cancer screening is unclear. The HPV FOr cerviCAL Cancer Trial (FOCAL) was a randomized trial comparing HPV testing with cytology. The FOCAL-DECADE cohort tracked women who received one HPV test during FOCAL, and were HPV negative, for up to 10 years to identify cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and grade 3 or worse (CIN3+) detected through a provincial screening program. METHODS: FOCAL participants who received one HPV test, were negative, and had at least one post-FOCAL cervix screen were included (N = 5,537). We constructed cumulative incidence curves of CIN2+/CIN3+ detection, analyzed cumulative risk of detection at intervals post-HPV test, calculated average incidence rates for detection, and compared hazard across ages. RESULTS: Ten years after one negative HPV test, the probability of CIN2+ detection was lower than 1%, with most lesions detected 7 years or later. Average incidence rates of CIN2+/CIN3+ lesions over follow-up were 0.50 [95% confidence interval (CI), 0.31-0.78] and 0.18 (95% CI, 0.07-0.36) per 1,000 person-years, respectively. Hazards were higher for younger ages (nonsignificant trend). CONCLUSIONS: Among women with a single negative HPV test, long-term risk of CIN2+ detection was low, particularly through 7 years of follow-up; thus, one negative HPV test appears to confer long-term protection from precancerous lesions. Even 10-year risk is sufficiently low to support extended testing intervals in average-risk populations. IMPACT: Our findings support the safety of screening policies using HPV testing alone at 5-year or longer intervals.

What is killing people with hepatitis C virus infection? Analysis of a population-based cohort in Canada.

BACKGROUND: Persons with hepatitis C virus (HCV) infection are at risk of mortality from both chronic liver disease and HCV acquisition risk activities. We compared causes of death among HCV positive and negative individuals to characterize contributions of acquisition risks and viral sequelae. METHODS: The British Columbia (BC) Hepatitis Testers Cohort (BC-HTC) includes all individuals tested for HCV or reported as a HCV case since 1992, linked to health administrative data. ICD-10 codes were used to classify deaths as: 1) liver-related (LR); 2) HCV acquisition risk-related (AR); and 3) other causes. Mortality proportions and trends were assessed among HCV positive and negative individuals overall and by birth cohort (born <1945, 1945-64 and ≥1965). RESULTS: As of December 31, 2018, of 1,300,204 HCV-tested individuals, 20,049 (27.5%) HCV positive and 132,999 (10.2%) HCV negative individuals had died (median age at death: 56.4 vs. 74.5 years, respectively). HCV positive individuals were more likely than negatives to die from both AR (24.7%/4.2%) and LR (23.4%/6.2%) causes. Deaths among older HCV positive individuals were more likely to be LR while younger individuals were more likely AR: 1) birth cohort <1945 (25.3%/2.7%); 2) 1945-64 (26.5%/23.7%) and ≥1965 (7.7%/59.9%). Among HCV positives, LR mortality increased from 1992 to 2014, then declined sharply, coinciding with the introduction and uptake of direct-acting antiviral drugs. AR mortality increased from 1992 to 2000, declined slowly until 2013, then rapidly increased, coinciding with the recent surge in opioid overdose deaths. CONCLUSIONS: Curative HCV treatments reduce LR mortality, but typically will not impact AR mortality. This will need to be addressed if the World Health Organization 2030 HCV mortality reduction goals are to be achieved.

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

Comparative performance of human papillomavirus messenger RNA versus DNA screening tests at baseline and 48 months in the HPV FOCAL trial.

BACKGROUND: HPV FOCAL is a randomized trial comparing high-risk HPV [Hybrid Capture 2 (HC2)] vs. liquid-based cytology (LBC) for primary cervical screening. OBJECTIVE: The present study objective was to compare Aptima HPV (AHPV) and HC2 assay performance at the intervention arm baseline and 48 mo. screens in relation to the rates of cervical intraepithelial neoplasia (CIN) grade 2 or worse (CIN2+). STUDY DESIGN: Women enrolled after December 2010 (n = 3475) were screened at baseline with both AHPV and HC2 (AHPV was blinded). Women with CIN2+ exited the trial; HC2 negative (-) women and those HC2 positive (+) with

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.

Aptima HPV Assay versus Hybrid Capture® 2 HPV test for primary cervical cancer screening in the HPV FOCAL trial.

BACKGROUND: Cervical cancer screening programs are switching from Pap screening to high-risk HPV testing. OBJECTIVES: To compare the Aptima HPV Assay (AHPV) with the Hybrid Capture® 2 High-Risk HPV DNA Test® (HC2) for primary cervical screening. STUDY DESIGN: HPV FOCAL is a randomized trial comparing HC2 to liquid-based cytology (LBC) for screening women aged 25-65. AHPV and HC2 were compared at the baseline screen (n=3473). Genotyping was by the Aptima HPV 16 18/45 Genotype Assay. We assessed HPV genotyping and reflex LBC for colposcopy triage. RESULTS: AHPV/HC2 agreement was 96.5% (kappa 0.76); positive agreement was 77.4%. The AHPV positive rate was 7.2% vs. 8.4% for HC2 (p=0.06). Based on HC2 screening, round 1 CIN2 and CIN3+ rates were 9.2/1000 and 5.2/1000 respectively. Using HC2 as the comparator test, AHPV CIN2+ and CIN3+ relative sensitivities were 0.96 and 1.00 (p=1.00) respectively. High-grade reflex LBC and HPV 16 infection were significantly associated with CIN3+. AHPV specificity was 0.94 vs. 0.93 (p=0.05) for HC2. Compared with triage of HC2+ with abnormal cytology or HPV persistence for 12 months, colposcopy referral would be significantly reduced (38.3/1000 vs. 60.8/1000; p<0.001) if AHPV+ women with abnormal LBC and HPV 16/18/45 were referred at baseline. CIN2+ and CIN3+ detection rates were not significantly different for the two strategies. CONCLUSIONS: AHPV vs. HC2 screening had equivalent CIN2+ and CIN3+ detection. Triage of AHPV+ by abnormal reflex LBC and the presence of HPV 16/18/45 would result in a significantly lower colposcopy referral rate with similar CIN2+ and CIN3+ detection rates as the overall HC2+ referral algorithm.

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.

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.

Towards targeted screening for acute HIV infections in British Columbia.

BACKGROUND: Our objective was to describe the characteristics of acute and established HIV infections diagnosed in the Canadian province of British Columbia. Province-wide HIV testing and surveillance data were analyzed to inform recommendations for targeted use of screening algorithms to detect acute HIV infections. METHODS: Acute HIV infection was defined as a confirmed reactive HIV p24 antigen test (or HIV nucleic acid test), a non-reactive or reactive HIV EIA screening test and a non-reactive or indeterminate Western Blot. Characteristics of unique individuals were identified from the British Columbia HIV/AIDS Surveillance System. Primary drug resistance and HIV subtypes were identified by analyzing HIV pol sequences from residual sera from newly infected individuals. RESULTS: From February 2006 to October 2008, 61 individuals met the acute HIV infection case definition, representing 6.2% of the 987 newly diagnosed HIV infections during the analysis period. Acute HIV infection cases were more likely to be men who have sex with men (crude OR 1.71; 95% CI 1.01-2.89], to have had a documented previous negative HIV test result (crude OR 2.89; 95% CI 1.52-5.51), and to have reported a reason for testing due to suspected seroconversion symptoms (crude OR 5.16; 95% CI 2.88-9.23). HIV subtypes and rates of transmitted drug resistance across all classes of drugs were similar in persons with both acute and established HIV infections. CONCLUSIONS: Targeted screening to detect acute HIV infection is a logical public health response to the HIV epidemic. Our findings suggest that acute HIV infection screening strategies, in our setting, are helpful for early diagnosis in men who have sex with men, in persons with seroconversion symptoms and in previously negative repeat testers.

A randomized controlled trial of Human Papillomavirus (HPV) testing for cervical cancer screening: trial design and preliminary results (HPV FOCAL Trial).

BACKGROUND: In the HPV FOCAL trial, we will establish the efficacy of hr-HPV DNA testing as a stand-alone screening test followed by liquid based cytology (LBC) triage of hr-HPV-positive women compared to LBC followed by hr-HPV triage with > or = CIN3 as the outcome. METHODS/DESIGN: HPV-FOCAL is a randomized, controlled, three-armed study over a four year period conducted in British Columbia. It will recruit 33,000 women aged 25-65 through the province's population based cervical cancer screening program. Control arm: LBC at entry and two years, and combined LBC and hr-HPV at four years among those with initial negative results and hr-HPV triage of ASCUS cases; Two Year Safety Check arm: hr-HPV at entry and LBC at two years in those with initial negative results with LBC triage of hr-HPV positives; Four Year Intervention Arm: hr-HPV at entry and combined hr-HPV and LBC at four years among those with initial negative results with LBC triage of hr-HPV positive cases DISCUSSION: To date, 6150 participants have a completed sample and epidemiologic questionnaire. Of the 2019 women enrolled in the control arm, 1908 (94.5%) were cytology negative. Women aged 25-29 had the highest rates of HSIL (1.4%). In the safety arm 92.2% of women were hr-HPV negative, with the highest rate of hr-HPV positivity found in 25-29 year old women (23.5%). Similar results were obtained in the intervention arm HPV FOCAL is the first randomized trial in North America to examine hr-HPV testing as the primary screen for cervical cancer within a population-based cervical cancer screening program. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Register, ISRCTN79347302.