Adjunctive use of p16 immunohistochemistry for optimizing management of CIN lesions in a high-risk human papillomavirus-positive population.

INTRODUCTION: Immunostaining with p16INK4a (p16), a tumor-suppressor surrogate protein biomarker for high-risk human papillomavirus (hrHPV) oncogenic activity, may complement standard hematoxylin and eosin (H&E) histology review, and provide more objective criteria to support the cervical intraepithelial neoplasia (CIN) diagnosis. With this study we assessed the impact of p16 immunohistochemistry on CIN grading in an hrHPV-based screening setting. MATERIAL AND METHODS: In this post-hoc analysis, 326 histology follow-up samples from a group of hrHPV-positive women were stained with p16 immunohistochemistry. All H&E samples were centrally revised. The pathologists reported their level of confidence in classifying the CIN lesion. RESULTS: Combining H&E and p16 staining resulted in a change of diagnosis in 27.3% (n = 89) of cases compared with the revised H&E samples, with a decrease of 34.5% (n = 18) in CIN1 and 22.7% (n = 15) in CIN2 classifications, and an increase of 18.3% (n = 19) in no CIN and 20.7% (n = 19) in CIN3 diagnoses. The level of confidence in CIN grading by the pathologist increased with adjunctive use of p16 immunohistochemistry to standard H&E. CONCLUSIONS: This study shows that adjunctive use of p16 immunohistochemistry to H&E morphology reduces the number of CIN1 and CIN2 classifications with a proportional increase in no CIN and CIN3 diagnoses, compared with standard H&E-based CIN diagnosis alone. The pathologists felt more confident in classifying the material with H&E and p16 immunohistochemistry than by using H&E alone, particularly during assessment of small biopsies. Adjunctive use of p16 immunohistochemistry to standard H&E assessment of CIN would be valuable for the diagnostic accuracy, thereby optimizing CIN management and possibly decreasing overtreatment.

Introduction of primary screening using high-risk HPV DNA detection in the Dutch cervical cancer screening programme: a population-based cohort study.

BACKGROUND: In January 2017, the Dutch cervical cancer screening programme transitioned from cytomorphological to primary high-risk HPV (hrHPV) DNA screening, including the introduction of self-sampling, for women aged between 30 and 60 years. The Netherlands was the first country to switch to hrHPV screening at the national level. We investigated the health impact of this transition by comparing performance indicators from the new hrHPV-based programme with the previous cytology-based programme. METHODS: We obtained data from the Dutch nationwide network and registry of histo- and cytopathology (PALGA) for 454,573 women eligible for screening in 2017 who participated in the hrHPV-based programme between 1 January 2017 and 30 June 2018 (maximum follow-up of almost 21 months) and for 483,146 women eligible for screening in 2015 who participated in the cytology-based programme between 1 January 2015 and 31 March 2016 (maximum follow-up of 40 months). We compared indicators of participation (participation rate), referral (screen positivity; referral rate) and detection (cervical intraepithelial neoplasia (CIN) detection; number of referrals per detected CIN lesion). RESULTS: Participation in the hrHPV-based programme was significantly lower than that in the cytology-based programme (61% vs 64%). Screen positivity and direct referral rates were significantly higher in the hrHPV-based programme (positivity rate: 5% vs 9%; referral rate: 1% vs 3%). CIN2+ detection increased from 11 to 14 per 1000 women screened. Overall, approximately 2.2 times more clinical irrelevant findings (i.e. ≤CIN1) were found in the hrHPV-based programme, compared with approximately 1·3 times more clinically relevant findings (i.e. CIN2+); this difference was mostly due to a national policy change recommending colposcopy, rather than observation, of hrHPV-positive, ASC-US/LSIL results in the hrHPV-based programme. CONCLUSIONS: This is the first time that comprehensive results of nationwide implementation of hrHPV-based screening have been reported using high-quality data with a long follow-up. We have shown that both benefits and potential harms are higher in one screening round of a well-implemented hrHPV-based screening programme than in an established cytology-based programme. Lower participation in the new hrHPV programme may be due to factors such as invitation policy changes and the phased roll-out of the new programme. Our findings add further to evidence from trials and modelling studies on the effectiveness of hrHPV-based screening.

Effectiveness of two strategies to follow-up ASC-US and LSIL screening results in The Netherlands using repeat cytology with or without additional hrHPV testing: a retrospective cohort study.

PURPOSE: The purpose of the study was to assess the effectiveness of repeat cytology with and without additional high-risk human papilloma virus (hrHPV) testing after atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion (ASC-US/LSIL) screening results. METHODS: In the Netherlands, ASC-US/LSIL is triaged by repeat cytology at 6 months or repeat cytology at 6 months with additional hrHPV testing. ASC-US/LSIL results from 13,734 screenees in 2008 were extracted from "Dutch Pathology Registry" including cytology, histology, and/or HPV follow-up results. Proportions of compliance, repeat cytology, referral, and detected cervical intraepithelial neoplasia (CIN) were assessed. RESULTS: With additional hrHPV testing, 46.8 % was send back to regular screening at 6 months, 28.6 % needed second repeat cytology, and 24.6 % was referred for colposcopy. Without additional hrHPV testing, this was 0.0, 76.1, and 23.9 %, respectively. With additional hrHPV testing, significantly higher proportions of persisting ASC-US/LSIL; compliance with repeat/referral advices; and histological detection of CIN0 (no CIN or cancer), CIN1, and CIN2 were found but equal proportions CIN3+. CONCLUSIONS: Additional hrHPV testing shortens follow-up without altering CIN3+ detection. Detection of CIN0, CIN1, and CIN2 was higher, presumably by hrHPV-driven biased cytology and detection bias. Restricting additional hrHPV testing to older women, reading cytology without knowledge of hrHPV status, and addition of more specific triage tests could further improve the effectiveness of additional hrHPV testing.

Liquid-based cervical cytology using ThinPrep technology: weighing the pros and cons in a cost-effectiveness analysis.

PURPOSE: Cervical cancer screening with liquid-based cytology (LBC) has been developed as an alternative to the conventional Papanicolaou (CP) smear. Cost-effectiveness is one of the issues when evaluating LBC. Based on the results of a Dutch randomised controlled trial, we conducted cost-effectiveness threshold analyses to investigate under what circumstances manually screened ThinPrep LBC is cost-effective for screening. METHODS: The MISCAN-Cervix microsimulation model and data from the Dutch NETHCON trial (including 89,784 women) were used to estimate the costs and (quality-adjusted) life years ((QA)LYs) gained for EU screening schedules, varying cost-effectiveness threshold values. Screening strategies were primary cytological screening with LBC or CP, and triage with human papillomavirus (HPV) testing. RESULTS: Threshold analyses showed that screening with LBC as a primary test can be cost-effective if LBC is less than 3.2 more costly per test than CP, if the sensitivity of LBC is at least 3-5 % points higher than CP, if the quality of life for women in triage follow-up is only 0.39, or if the rate of inadequate CP smears is at least 16.2 %. CONCLUSIONS: Regarding test characteristics and costs of LBC and CP, only under certain conditions will a change from CP to manually screened ThinPrep LBC be cost-effective. If none of these conditions are met, implementation of manually screened ThinPrep LBC seems warranted only if there are advantages other than cost-effectiveness. Further research is needed to establish whether other LBC systems will be more favorable with regard to cost-effectiveness.

Causes and relevance of unsatisfactory and satisfactory but limited smears of liquid-based compared with conventional cervical cytology.

CONTEXT: Recent randomized controlled trials have shown a significant decrease in unsatisfactory rates for liquid-based cytology (LBC) compared with conventional Papanicolaou test (CP). The underlying causes and relevance of unsatisfactory results for LBC and CP have never been compared within the setting of a randomized controlled trial. OBJECTIVE: To examine differences in causes and relevance of unsatisfactory and satisfactory but limited by (SBLB) results for LBC and CP. DESIGN: Data from the Netherlands ThinPrep Versus Conventional Cytology (NETHCON) trial were used, involving 89 784 women. Causes and relevance of unsatisfactory and SBLB results were analyzed. RESULTS: The primary cause for unsatisfactory results for CP and LBC was scant cellularity. Other causes for unsatisfactory CPs were virtually eliminated with LBC. The same was true for SBLB subcategories, with the exception of SBLB absence of transformation zone component and SBLB scant cellularity. The SBLB absence of transformation zone component showed a statistically significant 22% and SBLB scant cellularity a 12% nonsignificant increase with LBC. The detection rates of abnormalities found during 18 months of follow-up of unsatisfactory test results did not differ significantly between the 2 study arms, nor did they differ from the initial test positivity rates from the NETHCON trial. CONCLUSIONS: Liquid-based cytology shows an almost complete elimination of most causes for unsatisfactory CP, with scant cellularity remaining as the sole cause for unsatisfactory LBC. On the other hand, with LBC a significant increase of smears without a transformation zone component was noted. Women with an unsatisfactory test result are not at increased risk for cervical abnormalities either with LBC or with CP. TRIAL REGISTRATION: Nederlands Trial Register, NTR1032, www.trialregister.nl .

Patients with cervical cancer: why did screening not prevent these cases?

OBJECTIVE: The objective of the study was to assess the screening history of women with cervical cancer and review normal cervical smears 5 years preceding the diagnosis. STUDY DESIGN: Cytological and histological results of 401 women treated for invasive cervical cancer between 1991 and 2008 at the Radboud University Nijmegen Medical Center were studied. Ninety-eight normal smears were reviewed. RESULTS: Of the 401 women, 269 (67%) received at least 1 invitation for the national screening program for cervical cancer (NCSP). One- third fell outside the target age of the NCSP. Seventeen percent never responded to the invitation(s). Twenty-one percent had 1 or more normal smears within 5 years preceding the diagnosis. After review, only 39% of those smears were reviewed as a normal smear. CONCLUSION: Half of the women with cervical cancer were never screened because of the limited target age range or nonattendance. Twenty-one percent had a normal smear within 5 years preceding the diagnosis, caused by interpretation and/or sampling errors.

Comparison of liquid-based cytology with conventional cytology for detection of cervical cancer precursors: a randomized controlled trial.

CONTEXT: Liquid-based cytology has been developed as an alternative for conventional cervical cytology. Despite numerous studies and systematic reviews, controversy remains about its diagnostic accuracy. OBJECTIVE: To assess the performance of liquid-based cytology compared with conventional cytology in terms of detection of histologically confirmed cervical intraepithelial neoplasia (CIN). DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized controlled trial involving 89,784 women aged 30 to 60 years participating in the Dutch cervical screening program at 246 family practices. One hundred twenty-two practices were assigned to use liquid-based cytology and screened 49,222 patients and 124 practices were assigned to use the conventional Papanicolaou (Pap) test and screened 40,562 patients between April 2004 and July 1, 2006. Patients were followed up for 18 months through January 31, 2008. INTERVENTION: Screening for CIN using liquid-based cytology or conventional papanicolaou (Pap) test and the blinded review of all follow-up of screen-positive women (blinded to the type of cytology and the initial result). MAIN OUTCOME MEASURES: Intention-to-treat and per-protocol analysis of the detection rates of and positive predictive values for histologically verified CIN in both cytology systems. Outcomes are presented as crude and adjusted rate ratios (adjustment for age, urbanization, study site, and period). RESULTS: The adjusted detection rate ratios for CIN grade 1+ was 1.01 (95% confidence interval [CI], 0.85-1.19); for CIN grade 2+, 1.00 (95% CI, 0.84-1.20); for CIN grade 3+, 1.05 (95% CI, 0.86-1.29); and for carcinoma, 1.69 (95% CI, 0.96-2.99). The adjusted positive predictive value (PPV) ratios, considered at several cytological cutoffs and for various outcomes of CIN did not differ significantly from unity. CONCLUSION: This study indicates that liquid-based cytology does not perform better than conventional Pap tests in terms of relative sensitivity and PPV for detection of cervical cancer precursors. TRIAL REGISTRATION: trialregister.nl Identifier: NTR1032.