Viola M.J. Verhoef

Accuracy of human papillomavirus testing on self-collected versus clinician-collected samples: a meta-analysis

BACKGROUND Screening for human papillomavirus (HPV) infection is more effective in reducing the incidence of cervical cancer than screening using Pap smears. Moreover, HPV testing can be done on a vaginal sample self-taken by a woman, which offers an opportunity to improve screening coverage. However, the clinical accuracy of HPV testing on self-samples is not well-known. We assessed whether HPV testing on self-collected samples is equivalent to HPV testing on samples collected by clinicians. METHODS We identified relevant studies through a search of PubMed, Embase, and CENTRAL. Studies were eligible for inclusion if they fulfilled all of the following selection criteria: a cervical cell sample was self-collected by a woman followed by a sample taken by a clinician; a high-risk HPV test was done on the self-sample (index test) and HPV-testing or cytological interpretation was done on the specimen collected by the clinician (comparator tests); and the presence or absence of cervical intraepithelial neoplasia grade 2 (CIN2) or worse was verified by colposcopy and biopsy in all enrolled women or in women with one or more positive tests. The absolute accuracy for finding CIN2 or worse, or CIN grade 3 (CIN3) or worse of the index and comparator tests as well as the relative accuracy of the index versus the comparator tests were pooled using bivariate normal models and random effect models. FINDINGS We included data from 36 studies, which altogether enrolled 154 556 women. The absolute accuracy varied by clinical setting. In the context of screening, HPV testing on self-samples detected, on average, 76% (95% CI 69-82) of CIN2 or worse and 84% (72-92) of CIN3 or worse. The pooled absolute specificity to exclude CIN2 or worse was 86% (83-89) and 87% (84-90) to exclude CIN3 or worse. The variation of the relative accuracy of HPV testing on self-samples compared with tests on clinician-taken samples was low across settings, enabling pooling of the relative accuracy over all studies. The pooled sensitivity of HPV testing on self-samples was lower than HPV testing on a clinician-taken sample (ratio 0·88 [95% CI 0·85-0·91] for CIN2 or worse and 0·89 [0·83-0·96] for CIN3 or worse). Also specificity was lower in self-samples versus clinician-taken samples (ratio 0·96 [0·95-0·97] for CIN2 or worse and 0·96 [0·93-0·99] for CIN3 or worse). HPV testing with signal-based assays on self-samples was less sensitive and specific than testing on clinician-based samples. By contrast, some PCR-based HPV tests generally showed similar sensitivity on both self-samples and clinician-based samples. INTERPRETATION In screening programmes using signal-based assays, sampling by a clinician should be recommended. However, HPV testing on a self-sample can be suggested as an additional strategy to reach women not participating in the regular screening programme. Some PCR-based HPV tests could be considered for routine screening after careful piloting assessing feasibility, logistics, population compliance, and costs. FUNDING The 7th Framework Programme of the European Commission, the Belgian Foundation against Cancer, the International Agency for Research on Cancer, and the German Guideline Program in Oncology.

High-risk HPV testing on self-sampled versus clinician-collected specimens: a review on the clinical accuracy and impact on population attendance in cervical cancer screening.

This review elaborates on the accuracy and feasibility of human papillomavirus (HPV) self‐sampling, i.e., offering self‐sampling of (cervico‐)vaginal cell material by women themselves in nonclinical settings for high‐risk HPV (hrHPV) detection in the laboratory, for cervical screening. To that end a bibliographic database search (PubMed) was performed to identify studies (published between January 1992 and January 2012) that compared clinical accuracy of HPV testing on self‐sampled material with that of cytology or HPV testing on clinician‐taken samples, and studies comparing response to offering HPV self‐sampling with a recall invitation. Overall, hrHPV testing on self‐samples appeared to be at least as, if not more, sensitive for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) as cytology on clinician‐obtained cervical samples, though often less specific. In most studies, hrHPV testing on self‐ and clinician‐sampled specimens is similarly accurate with respect to CIN2+ detection. Variations in clinical performance likely reflect the use of different combinations of collection devices and HPV tests. Because it is known that underscreened women are at increased risk of cervical cancer, targeting non‐attendees of the screening program could improve the effectiveness of cervical screening. In developed countries offering self‐sampling has shown to be superior to a recall invitation for cytology in re‐attracting original non‐attendees into the screening program. Additionally, self‐testing has shown to facilitate access to cervical screening for women in low resource areas. This updated review of the literature suggests that HPV self‐sampling could be an additional strategy that can improve screening performance compared to current cytology‐based call‐recall programs.

Comparative performance of novel self-sampling methods in detecting high-risk human papillomavirus in 30,130 women not attending cervical screening.

We determined whether the participation rate for a brush‐based cervicovaginal self‐sampling device is noninferior to the participation rate for a lavage‐based one for testing for hrHPV (high‐risk human papillomavirus). Additionally, positivity rates for hrHPV, the detection rates for cervical intraepithelial neoplasia grades 2 and 3 or worse (CIN2+/3+), and user comfort were compared. A total of 35,477 non‐responders of the regular cervical screening program aged 33–63 years were invited to participate. Eligible women (n = 30,130) were randomly assigned to receive either a brush‐based or a lavage‐based device, and a questionnaire for reporting user convenience. Self‐sampling responders testing hrHPV‐positive were invited for a physician‐taken sample for cytology; triage‐positive women were referred for colposcopy. A total of 5,218 women participated in the brush‐based sampling group (34.6%) and 4809 women in the lavage‐based group (31.9%), i.e. an absolute difference of 2.7% (95%CI 1.8–4.2). The hrHPV‐positivity rates in the two groups were identical (8.3%, relative risk (RR) 0.99, 95%CI 0.87–1.13). The detection of CIN2+ and CIN3+ in the brush group (2.0% for CIN2+; 1.3% for CIN3+) was similar to that in the lavage group (1.9% for CIN2+; 1.0% for CIN3+) with a cumulative RR of 1.01, 95%CI 0.83–1.24 for CIN2+ and 1.25, 95%CI 0.92–1.70 for CIN3+. The two self‐sampling devices performed similarly in user comfort. In conclusion, offering a brush‐based device to non‐responders is noninferior to offering a lavage‐based device in terms of participation. The two self‐sampling methods are equally effective in detecting hrHPV, CIN2+/CIN3+ and are both well accepted.

Validation of the FAM19A4/mir124-2 DNA methylation test for both lavage- and brush-based self-samples to detect cervical (pre)cancer in HPV-positive women

Objectives DNA methylation analysis of cancer-related genes is a promising tool for HPV-positive women to identify those with cervical (pre)cancer (CIN3+) in need of treatment. However, clinical performance of methylation markers can be influenced by the sample type utilized. We describe a multiplex quantitative methylation-specific PCR that targets FAM19A4 and mir124-2 loci, to detect CIN3+ using both HPV-positive lavage- and brush self-samples. Methods We determined methylation thresholds for clinical classification using HPV-positive training sets comprising lavage self-samples of 182 women (including 40 with CIN3+) and brush self-samples of 224 women (including 61 with CIN3+). Subsequently, independent HPV-positive validation sets of 389 lavage self-samples (including 78 with CIN3+), and 254 brush self-samples (including 72 with CIN3+) were tested using the preset thresholds. Furthermore, the clinical performance of combined methylation analysis and HPV16/18 genotyping was determined. Results Training set analysis revealed similar FAM19A4 and mir124-2 thresholds for both self-sample types to yield highest CIN3+ sensitivity at 70% specificity. Validation set analysis resulted in a CIN3+ sensitivity of 70.5% (95%CI: 60.4–80.6) at a specificity of 67.8% (95%CI: 62.7–73.0) for lavage self-samples, and a CIN3+ sensitivity of 69.4% (95%CI: 58.8–80.1) at a 76.4% (95%CI: 70.2–82.6) specificity for brush self-samples. In combination with HPV16/18 genotyping, CIN3+ sensitivity and specificity were 88.5% (95%CI: 81.4–95.6) and 46.0% (95%CI: 40.4–51.5) for lavage self-samples, and 84.7% (95%CI: 76.4–93.0) and 54.9% (95%CI: 47.7–62.2) for brush self-samples. Conclusions FAM19A4/mir124-2 methylation analysis performs equally well in HPV-positive lavage- and brush self-samples to identify women with CIN3+. In combination with HPV16/18 genotyping, significantly higher CIN3+ sensitivities are obtained, at decreased specificity.

Methylation marker analysis and HPV16/18 genotyping in high-risk HPV positive self-sampled specimens to identify women with high grade CIN or cervical cancer

OBJECTIVES Methylation marker analysis using bi-marker panel MAL/miR-124-2 is a promising triage test for identifying cervical (pre)cancer in high-risk human papillomavirus (hrHPV) positive women. Bi-marker panel MAL/miR-124-2 can be applied directly on self-sampled cervico-vaginal material and its sensitivity is non-inferior to that of cytology, yet at the cost of more colposcopy referrals. Our objective was to increase specificity of MAL/miR-124-2 methylation analysis by varying the assay thresholds and adding HPV16/18 genotyping. METHODS 1019 hrHPV-positive women were selected from a randomized controlled self-sampling trial (PROHTECT-3; 33-63 years, n=46,001) and nine triage strategies with methylation testing of MAL/miR-124-2 and HPV16/18 genotyping were evaluated. The methylation assay threshold was set at four different predefined levels which correspond with clinical specificities for end-point cervical intra-epithelial grade 3 or worse (CIN3+) of 50%, 60%, 70%, and 80%. RESULTS The CIN3+ sensitivity of methylation analysis decreased (73.5 to 44.9%) while specificity increased (47.2 to 83.4%) when increasing the assay threshold. CIN3+ sensitivity and specificity of HPV16/18 genotyping were 68.0% and 65.6%, respectively. Combined methylation analysis at threshold-80 and HPV16/18 genotyping yielded similar CIN3+ sensitivity as that of methylation only at threshold-50 (77.6%) with an increased specificity (54.8%). CONCLUSIONS Combined triage by MAL/miR-124-2 methylation analysis with threshold-80 and HPV16/18 genotyping reaches high CIN3+ sensitivity with increased specificity to identify women with cervical (pre)cancer among HPV self-sample positive women. The combined strategy is attractive as it is fully molecular and identifies women at the highest risk of cervical (pre)cancer because of strongly elevated methylation levels and/or HPV16/18 positivity.

NOX5 Expression Is Increased in Intramyocardial Blood Vessels and Cardiomyocytes after Acute Myocardial Infarction in Humans

Reactive oxygen species producing NADPH oxidases play important roles under different (patho)physiological conditions. NOX1, NOX2, and NOX4 are important sources of reactive oxygen species in the heart, but knowledge of the calcium-dependent NOX5 in the heart is lacking. The presence of NOX5 was studied via RT-PCR in heart tissue from patients with end-stage heart failure; the tissue was obtained during cardiac transplantation surgery. NOX5 positivity and cellular localization were studied via IHC and digital-imaging microscopy in heart tissues of patients who did not have heart disease and in infarction areas of patients who died of myocardial infarctions of different durations. Furthermore, NOX5 expression was analyzed in vitro by using Western blot analysis. NOX5 RNA was found in the hearts of controls and patients with ischemic cardiomyopathy. In controls, NOX5 localized to the endothelium of a limited number of intramyocardial blood vessels and to a limited number of scattered cardiomyocytes. In infarcted hearts, NOX5 expression increased, especially in infarctions >12 hours, which manifested as an increase in NOX5-positive intramyocardial blood vessels, as well as in endothelium, smooth muscle, and cardiomyocytes. NOX5 was found in cardiomyocyte cytoplasm, plasma membrane, intercalated disks, and cross striations. Western blot analysis confirmed NOX5 expression in isolated human cardiomyocytes. For the first time to our knowledge, we demonstrate NOX5 expression in human intramyocardial blood vessels and cardiomyocytes, with significant increases in the affected myocardium after acute myocardial infarction.

Follow-up of high-risk HPV positive women by combined cytology and bi-marker CADM1/MAL methylation analysis on cervical scrapes

OBJECTIVES Triage of HPV screen-positive women is needed to identify those with underlying cervical intraepithelial neoplasia grade 2/3 or worse (CIN2/3+). Presently, cytology on a physician-taken cervical scrape is mostly accepted as triage test, but needs follow-up testing in order not to miss severe disease. Here, we evaluated the performance of combined cytology and bi-marker CADM1/MAL-methylation analysis as triage test on physician-taken cervical scrapes of HPV positive women. METHODS In this post-hoc analysis, we used 364 left-over HPV positive cytology triage samples of participants of a randomized controlled trial (PROHTECT-3: n=46,001) performed in population-based cervical screening. Study endpoints were CIN2+ and CIN3+ detection. Cytology testing with and without methylation marker analysis was evaluated with regard to sensitivity, specificity, positive and negative predictive value, and referral rate. RESULTS Bi-marker CADM1/MAL-methylation positivity increased proportionally with severity of underlying lesions. Overall, cytology and bi-marker CADM1/MAL-methylation analysis yielded similar performances with regard to CIN3+ detection, yet in combination a significantly higher sensitivity for CIN3+ (88.7%) was obtained at a specificity of 53.6% and a colposcopy referral rate of 53.6%. The combined strategy detected all six cervical cancers, whereas triage by cytology alone failed to detect two of them. CONCLUSIONS Cytology and bi-marker CADM1/MAL-methylation analysis perform complementary for CIN2+/CIN3+ detection when used as triage tool on cervical scrapes of HPV positive women. This approach not only results in a higher CIN3+ sensitivity than cytology triage with an acceptable referral rate, but also seems to reduce the risk of missing cervical cancers and advanced high-grade lesions.

The clinical value of HPV genotyping in triage of women with high‐risk‐HPV‐positive self‐samples

Cytology alone, or combined with HPV16/18 genotyping, might be an acceptable method for triage in hrHPV‐cervical cancer screening. Previously studied HPV‐genotype based triage algorithms are based on cytology performed without knowledge of hrHPV status. The aim of this study was to explore the value of hrHPV genotyping combined with cytology as triage tool for hrHPV‐positive women. 520 hrHPV‐positive women were included from a randomised controlled self‐sampling trial on screening non‐attendees (PROHTECT‐3B). Eighteen baseline triage strategies were evaluated for cytology and hrHPV genotyping (Roche Cobas 4800) on physician‐sampled triage material. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), referral rate, and number of referrals needed to diagnose (NRND) were calculated for CIN2+ and CIN3+. A triage strategy was considered acceptable if the NPV for CIN3+ was ≥98%, combined with maintenance or improvement of sensitivity and an increase in specificity in reference to the comparator, being cytology with a threshold of atypical cells of undetermined significance (ASC‐US). Three triage strategies met the criteria: HPV16+ and/or ≥LSIL; HPV16+ and/or ≥HSIL; (HPV16+ and/or HPV18+) and/or ≥HSIL. Combining HPV16+ and/or ≥HSIL yielded the highest specificity (74.9%, 95% CI 70.5–78.9), with a sensitivity (94.4%, 95% CI 89.0–97.7) similar to the comparator (93.5%, 95% CI 87.7–97.1), and a decrease in referral rate from 52.2% to 39.5%. In case of prior knowledge of hrHPV presence, triage by cytology testing can be improved by adjusting its threshold, and combining it with HPV16/18 genotyping. These strategies improve the referral rate and specificity for detecting CIN3+ lesions, while maintaining adequate sensitivity.

A second generation cervico-vaginal lavage device shows similar performance as its preceding version with respect to DNA yield and HPV DNA results

BackgroundAttendance rates of cervical screening programs can be increased by offering HPV self-sampling to non-attendees. Acceptability, DNA yield, lavage volumes and choice of hrHPV test can influence effectiveness of the self-sampling procedures and could therefore play a role in recruiting non-attendees. To increase user-friendliness, a frequently used lavage sampler was modified. In this study, we compared this second generation lavage device with the first generation device within similar birth cohorts.MethodsWithin a large self-sampling cohort-study among non-responders of the Dutch cervical screening program, a subset of 2,644 women received a second generation self-sampling lavage device, while 11,977 women, matched for age and ZIP-code, received the first generation model. The second generation device was different in shape, color, lavage volume, and packaging, in comparison to its first generation model. The Cochran’s test was used to compare both devices for hrHPV positivity rate and response rate. To correct for possible heterogeneity between age and ZIP codes in both groups the Breslow-Day test of homogeneity was used. A T-test was utilized to compare DNA yields of the obtained material in both groups.ResultsMedian DNA yields were 90.4 μg/ml (95% CI 83.2-97.5) and 91.1 μg/ml (95% CI 77.8-104.4, p= 0.726) and hrHPV positivity rates were 8.2% and 6.9% (p= 0.419) per sample self-collected by the second - and the first generation of the device (p= 0.726), respectively. In addition, response rates were comparable for the two models (35.4% versus 34.4%, p= 0.654).ConclusionsReplacing the first generation self-sampling device by an ergonomically improved, second generation device resulted in equal DNA yields, comparable hrHPV positivity rates and similar response rates. Therefore, it can be concluded that the clinical performance of the first and second generation models are similar. Moreover, participation of non-attendees in cervical cancer screening is probably not predominantly determined by the type of self-collection device.

Evaluation of p16/Ki-67 dual-stained cytology as triage test for high-risk human papillomavirus-positive women

The aim of this study was to evaluate the clinical utility of p16/Ki-67 dual staining, for the identification of CIN in high-risk HPV-positive women from a non-responder screening cohort. P16/Ki-67 dual staining, Pap cytology, and HPV16/18 genotyping were performed on physician-taken liquid-based samples from 495 women who tested high-risk HPV positive on self-sampled material (PROHTECT-3B study). Different triage strategies involving p16/Ki-67 dual staining were evaluated for sensitivity, specificity, and predictive value for ≥CIN2 and ≥CIN3, and compared to Pap cytology with a threshold of atypical cells of undetermined significance. Centrally revised histology or an adjusted endpoint with combined high-risk HPV negative and cytology negative follow-up at 6 months was used as gold standard. Pap cytology (threshold atypical cells of undetermined significance) triage of high-risk HPV-positive samples showed a sensitivity of 93% (95% confidence interval: 85–98) with a specificity of 49% (95% confidence interval: 41–56) for ≥CIN3. Three triage strategies with p16/Ki-67 showed a significantly increased specificity with similar sensitivity. P16/Ki-67 triage of all high-risk HPV-positive samples had a sensitivity of 92% (95% confidence interval: 84–97) and a specificity of 61% (95% confidence interval: 54–69) for ≥CIN3. Applying p16/Ki-67 triage to only high-risk HPV-positive women with low-grade Pap cytology showed a similar sensitivity of 92% (95% confidence interval: 84–97), with a specificity for ≥CIN3 of 64% (95% confidence interval: 56–71). For high-risk HPV-positive women with low-grade and normal Pap cytology, triage with p16/Ki-67 showed a sensitivity of 96% (95% confidence interval: 89–99), and a specificity of 58% (95% confidence interval: 50–65). HPV16/18 genotyping combined with Pap cytology showed a sensitivity and specificity for ≥CIN3 similar to Pap cytology with an atypical cells of undetermined significance threshold. Because the quality of Pap cytology worldwide varies, and differences in sensitivity and specificity are limited between the three selected strategies, p16/Ki-67 triage of all high-risk HPV-positive samples would be the most reliable strategy in triage of high-risk HPV-positive women with an increased specificity and similar sensitivity compared with Pap cytology triage.