Quality assurance of human papillomavirus (HPV) testing in the implementation of HPV primary screening in Norway: an inter-laboratory reproducibility study

Performance of a 7-Type HPV mRNA Test in Triage of HPV DNA Primary Screen Positive Women Compared to Liquid-Based Cytology

Background: A plethora of data supports HPV-based screening to be the preferred strategy for cervical cancer prevention. The shift to a more sensitive first-line test brings the need of effective triage up for discussion. Currently, most algorithms apply cytology as a triage of HPV-DNA positive women. This study compared the performance of a 7-type HPV-mRNA test to cytology. Methods: From 1 January 2019 until 31 December 2021, cervical samples from 58,029 women were examined at the University Hospital of North Norway. A total of 30.5% (17,684/58,029) fulfilled the criteria for HPV-DNA primary screening. All positive samples were triaged by cytology and followed-up according to national guidelines through 2022. Additionally, a 7-type HPV-mRNA test was applied. The study endpoint was a histologically confirmed high-grade lesion (CIN2+). Results: A total of 5.6% (990/17,684) had positive HPV-DNA test, 97.2% (962/990) with valid HPV-mRNA results. A total of 55.5% (534/962) had abnormal cytology (ASC-US+), and 35.1% (338/962) had a positive HPV-mRNA test. A total of 13.9% (134/962) had CIN2+. The sensitivity (CIN2+) of cytology versus the HPV-mRNA test was 76.1% (102/134) versus 73.1% (98/134), p = 0.67. The specificity was 47.8% (396/828) versus 71.0% (588/624), p < 0.001. PPV was 19.1% (102/534) and 29.0% (98/338), p < 0.001, respectively. The number of colposcopies per CIN2+ detected by cytology and HPV-mRNA test was 5.2 and 3.1. Conclusion: The 7-type HPV mRNA test was significantly more specific than cervical cytology in a triage of HPV-DNA positive women. Using this biomarker as the threshold for colposcopy may better balance the benefits and harms of screening.

Quality assurance in human papillomavirus testing for primary cervical screening

The recommendation for cervical screening is that it should be based on human papillomavirus (HPV) molecular testing. For all screening programs, attention to quality assurance is required to fully realize the benefits. Internationally recognized quality assurance recommendations for HPV-based screening are needed that are ideally applicable for a variety of settings, including in low- and middle-income countries. We summarize the main points of quality assurance for HPV screening, with a focus on the selection, implementation, and use of an HPV screening test, quality assurance systems (including internal quality control and external quality assessment), and staff competence. While we recognize that it might not be possible to fulfill all points in all settings, an awareness of the issues is essential.

High-Risk Human Papillomavirus Detection via Cobas® 4800 and REBA HPV-ID® Assays

Persistent infection with high-risk human papillomaviruses (HR-HPVs), particularly HPV16 and 18, has long been known to induce cervical cancer progression. However, given that a minority of HPV-infected women develop cancer, analysis of HR-HPV-infected women could help to predict who is at risk of acquiring cervical cancer. Therefore, to improve HR-HPVs detection, we used the FDA-approved cobas^® 4800 HPV and REBA HPV-ID^® HPV assays to detect HR-HPVs in colposcopy-derived cervical cells from 303 patients, detecting 72.28% (219) and 71.62% (217) of HR-HPVs positive cases, with HPV16 detection rates of 35.64% (108) and 30.69% (93), respectively. Of the HPV16-positive cases, cobas^® 4800 and REBA HPV-ID^® identified 28.81% (51) and 25.42% (45) of the CIN1 cases, and 55% (33) and 50% (30) of the 60 CIN2/3 cases, respectively. HPV-diagnostic concordance was 82.17% overall (kappa = 0.488), 87.45% for HR-HPVs (kappa = 0.689), and 88.33% for CIN2/3 (kappa = 0.51). The HR-HPVs detection rates of these assays were comparable. Our findings reveal that the FDA-approved HR-HPVs detection assay is appropriate for screening women with HR-HPVs infection, and for predicting increased risk of cervical cancer progression. REBA HPV-ID^® can be used to detect low risk-HPV types in high-grade cervical lesions that are HR-HPV negative as well as in the distribution of HPV types.

Randomized Implementation of a Primary Human Papillomavirus Testing-based Cervical Cancer Screening Protocol for Women 34 to 69 Years in Norway

BACKGROUND

Cervical cancer screening programs are facing a programmatic shift where screening protocol based on human papillomavirus testing (HPV-Screening protocol) is replacing the liquid-based cytology (LBC-Screening protocol). For safe technology transfer within the nationwide screening programme in Norway, HPV-Screening protocol was implemented randomized to compare the real-world effectiveness of HPV-Screening protocol and LBC-Screening protocol at the first screening round.

METHODS

Among 302,295 women ages 34 to 69 years scheduled to attend screening from February 2015 to June 2017, 157,447 attended. A total of 77,207 were randomly allocated to the HPV-Screening protocol and 80,240 were allocated to the LBC-Screening protocol. All women were followed up for 18 months.

RESULTS

The HPV-Screening protocol resulted in a relative increase of 60% in the detection of cervical intraepithelial neoplasia (CIN) grade 2 or worse [risk ratio (RR) = 1.6, 95% confidence interval (CI) = 1.5-1.7], 40% in CIN grade 3 or worse (RR = 1.4, 95% CI = 1.3-1.6), 40% in cancer (RR = 1.4, 95% CI = 1.0-2.1), and 60% in colposcopy referrals (RR = 1.6, 95% CI = 1.5-1.6) compared with LBC-Screening. The performance of both protocols was age dependent, being more effective in women ages under 50 years.

CONCLUSIONS

The HPV-Screening protocol was well accepted by women in Norway and detected more CIN2, CIN3, and cancers compared with the LBC-Screening protocol.

IMPACT

A randomized implementation of the HPV-Screening protocol with real-world assessment enabled a gradual, quality assured, and safe technology transition. HPV-based screening protocol may further be improved by using HPV genotyping and age-specific referral algorithms.

Cervical cancer in women under 30 years of age in Norway: a population-based cohort study

BACKGROUND

We compared women with incident cervical cancer under the age of 30 with older women with regard to stage, morphology, screening history and cervical cancer mortality in a population-based cohort study.

METHODS

We included data from the Cancer Registry of Norway. Incidence rates (per 100,000 women-years) were calculated and joinpoint regression was used to analyse trends. The Nelson-Aalen cumulative hazard function for risk of cervical cancer death during a 15-year follow-up was displayed. The hazard ratios (HRs) of cervical cancer mortality with 95% confidence intervals (CIs) were derived from Cox regression models.

RESULTS

The incidence of cervical cancer in women under the age of 30 has almost tripled since the 1950s, with the steepest increase during 1955-80 (with an annual percentage change (APC) of 7.1% (95%CI 4.4-9.8)) and also an increase after 2004 (3.8% (95%CI -1.3-9.2)). Out of 21,160 women with cervical cancer (1953-2013), 5.3% were younger than 30 years. A lower proportion of younger women were diagnosed at more advanced stages and a slightly higher proportion were diagnosed with adenocarcinoma and adenosquamous carcinoma comparing women above 30 years. The cumulative risk of cervical cancer death was lower for patients under the age of 30. However, the difference between the age groups decreased over time. The overall adjusted HR of cervical cancer mortality was 0.69 (95% CI 0.58-0.82) in women diagnosed under the age of 30 compared to older women.

CONCLUSION

There has been an increase in cervical cancer incidence in women under the age of 30. Cervical cancer in younger women was not more advanced at diagnosis compared to older women, and the cervical cancer mortality was lower.

Performance and acceptability of self-collected human papillomavirus testing among women living with HIV

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Women living with HIV are under-screened for cervical cancer.

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Human papillomavirus (HPV) self-testing at home could become a more efficient strategy in the post-COVID-19 era.

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Self-collected HPV testing has good sensitivity and moderate specificity among women living with HIV.

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Self-sampling is highly accepted by women.

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Improvement in self-sampling techniques is needed due to possibly inadequate sample volume.

Objective

To assess the validity, reliability, and acceptability of self-collected human papillomavirus (HPV) tests in women living with HIV (WLHIV) in the United States.

Methods

WLHIV ≥30 years of age underwent self-collected (clinic and home) and clinician-collected HPV tests. Sensitivity and specificity analyses were performed using the clinician-collected HPV tests as the comparator. The unweighted kappa statistic was used to evaluate the validity and reliability of self-collected HPV testing, and the level of agreement between the clinician-collected mRNA test and a DNA test that was used for routine care. A 13-question survey was used to assess acceptability.

Results

Among the 70 participants, the median age was 50 years, 75% had an undetectable HIV RNA, and 11% had a CD4 count of <200 cells/μl. Nearly 63% had at least one positive HPV test. The sensitivity and specificity of the self-collected HPV test were 84.6% (95% confidence interval (CI) 65.1–95.6%) and 62.9% (95% CI 44.9–78.5%), respectively (κ = 0.5, 95% CI 0.2–0.7). The agreement between the two self-collected tests was good (κ = 0.8, 95% CI 0.5–1.0). There was good agreement between clinician-collected mRNA tests and DNA tests (κ = 0.8, 95% CI 0.7–1.0). Self-collection was highly acceptable.

Conclusions

Among WLHIV, self-collected HPV tests had good sensitivity and moderate specificity compared to clinician-collected HPV tests. The reliability between self-collected testing locations was good. Self-collected HPV testing had high acceptability.

Real-world data on cervical cancer risk stratification by cytology and HPV genotype to inform the management of HPV-positive women in routine cervical screening

BACKGROUND

HPV16/18 detection may improve cervical cancer risk stratification and better guide which HPV-positive women warrant immediate colposcopy/biopsy. We estimated risks of cervical precancer and cancer by HPV genotype and cytology during the implementation phase of primary HPV testing in Norway.

METHODS

A total of 3111 women, aged 34-69 years, testing HPV-positive at baseline and undergoing cytology testing from February 2015 to April 2018 had data available for analysis. Risk estimates with 95% confidence intervals (95%CIs) of cervical intraepithelial neoplasia grade 3 or more severe (CIN3+) were estimated for cytology results and HPV genotypes (HPV16, HPV18, and other high-risk HPV).

RESULTS

CIN3+ risks were higher for HPV16/18 than other high-risk HPV genotypes. Among women with any cytologic abnormality [atypical squamous cells of undetermined significance or worse], immediate risks were 57.8% (95%CI = 53.0-62.6%) for HPV16, 40.2% (95%CI = 32.3-49.2%) for HPV18, and 31.4% (95%CI = 28.7-34.3%) for other high-risk HPV. Among those with normal cytology, CIN3+ risks were 19.9% (95%CI = 15.0-26.1%) for HPV16 positives, 10.8% (95%CI = 5.6-20.5%) for HPV18 positives, and 5.5% (95%CI = 4.2-7.1%) for other high-risk HPV.

CONCLUSIONS

The benefits and harms of managing women based on HPV positivity and cytology results can be better balanced by inclusion of HPV genotyping in screening and choosing more conservative management for other high-risk HPV compared to HPV16/18.

HPV testing for cervical cancer screening: technical improvement of laboratory logistics and good clinical performance of the cobas 6800 in comparison to the 4800 system

BACKGROUND

European guidelines for cervical cancer screening now recommend the use of clinically validated assays for high-risk HPV-DNA sequences as primary test in women older than 30 years, performed in centralized laboratories, and run on systems providing automated solutions for all steps.

METHODS

We conducted a comparison study, according to the international guidelines, nested within the organized population-based cervical screening program, between the cobas 4800 and 6800 systems (Roche Diagnostics), to evaluate accuracy and reproducibility of HPV test results and laboratory workflow. In Italy implementation of HPV cervical screening is under way on a regional basis; in Veneto it started in June 2015, following a piloting phase; the assay in use in the three centralized laboratories is the cobas 4800 HPV test, run on the cobas 4800 system. Comparison of HPV results with a new version of the assay (cobas 6800/8800 HPV) run on the cobas 6800 system, and intra- and inter-reproducibility analyses have been conducted in samples collected in PreservCyt medium (Hologic) from women without and with a subsequent diagnosis of high-grade lesion.

RESULTS

Samples from women older than 30 years attending organized cervical cancer screening were used. Clinical sensitivity and specificity were evaluated on 60 cases and 925 controls, respectively; intra-laboratory reproducibility and inter-laboratory agreement by the 6800 system were evaluated on 593 and 460 specimens, respectively. Our results showed a very high agreement (> 98%) for overall qualitative results between the two systems; clinical sensitivity and specificity of the HPV assay run on 6800 were non-inferior to those of the HPV assay run on 4800 (p = 0,0157 and p = 0,0056, respectively, at the recommended thresholds of 90 and 98%); kappa values of 0.967 and 0.969 were obtained for intra- and inter-laboratory reproducibility analyses in the 6800 system. The 6800 platform displayed several technological improvements over the 4800 system, with higher throughput and laboratory productivity, and lower operator's hands-on time.

CONCLUSIONS

The new cobas 6800/8800 HPV assay run on the 6800 instrument is suitable for use in large centralized laboratories included within population-based cervical cancer screening programs.

Cervical Cancer Screening Programs in Europe: The Transition Towards HPV Vaccination and Population-Based HPV Testing

Cervical cancer is the fourth most frequently occurring cancer in women around the world and can affect them during their reproductive years. Since the development of the Papanicolaou (Pap) test, screening has been essential in identifying cervical cancer at a treatable stage. With the identification of the human papillomavirus (HPV) as the causative agent of essentially all cervical cancer cases, HPV molecular screening tests and HPV vaccines for primary prevention against the virus have been developed. Accordingly, comparative studies were designed to assess the performance of cervical cancer screening methods in order to devise the best screening strategy possible. This review critically assesses the current cervical cancer screening methods as well as the implementation of HPV vaccination in Europe. The most recent European Guidelines and recommendations for organized population-based programs with HPV testing as the primary screening method are also presented. Lastly, the current landscape of cervical cancer screening programs is assessed for both European Union member states and some associated countries, in regard to the transition towards population-based screening programs with primary HPV testing.

Development of a pilot proficiency program for human papillomavirus DNA detection

Human papillomavirus (HPV) DNA testing has become routine in many diagnostic laboratories, particularly with changes from cervical cytology to HPV DNA as primary screening as of 1 December 2017 in Australia. External quality assurance (EQA) is essential for assessment of laboratory performance once HPV testing is implemented. The aim of this study was to develop a pilot program to evaluate and determine stability of material that could be utilised in an ongoing external quality assurance program (EQAP). Two sample types were evaluated: cells in PreservCyt solution (ThinPrep) from stored clinical specimens and HPV-seeded swabs. Two panels sent 5 months apart were distributed to 18 Australian and two New Zealand laboratories (participants) for testing by Hybrid Capture 2 (HC2) or alternative molecular methods. Participants were given 1 month to test specimens. Eight ThinPrep specimens in Panel 1 were reported correctly by 73% (11/15) of HC2 participants and 40% (2/5) of participants performing alternative methods. Of eight dry swab specimens, 58% (23/40) and 78% (25/32) were correctly identified by HC2 and alternative methods, respectively. Panel 2 included four ThinPrep and two swab specimens. ThinPrep specimens were reported correctly by 100% (60/60) of participants utilising HC2 and 95% (19/20) utilising alternative methods. Dry swab specimens were reported correctly by 89% (25/28) of participants utilising HC2 and 100% (10/10) of participants utilising alternative methods. These results indicate that both specimen types are suitable for utilisation in an EQAP and outline some issues of EQAP for ongoing assessment of HPV molecular methods in diagnostic molecular laboratories.