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 <CIN2); Group 2: 103 HPV+, normal cytology with HPV persistence at 12 mo. (53 CIN2/3; 50 <CIN2); Group 3: 50 HPV+, normal cytology with HPV clearance at 12 mo. (assumed <CIN2), total n=257. For the combined groups, S5 risk score CIN2/3 relative sensitivity, specificity and positive predictive value (PPV) were compared with other triage approaches. Methylation showed a highly significant increasing trend with disease severity. For CIN3, S5 relative sensitivity and specificity were: 93.2% (95%CI: 81.4–98.0) and 41.8% (35.2–48.8), compared to 86.4% (75.0–95.7) and 49.8% (43.1–56.6) respectively for combined abnormal cytology/HPV16/18 positivity (differences not statistically significant at 5% level); adjusted PPVs were 18.2% (16.2–20.4) and 19.3% (16.6–22.2) respectively. S5 was also positive in baseline specimens from eight cancers detected during or after trial participation. The S5 methylation score had high sensitivity and PPV for CIN3, compatible with US and European thresholds for colposcopy referral. Methylation signatures can identify most HPV positive women at increased risk of cervical cancer from their baseline screening specimens.
What's new?
DNA methylation testing could simplify the triage process for screening HPV+ women for cervical cancer, according to new results from a case‐control study. Most pre‐cancerous cervical lesions do not progress to cancer, so triage is done to identify those lesions more likely to become cancerous and boost screening specificity. Here, the authors tested women in the HPV FOCAL study for baseline methylation using the S5 classifier. Methylation signatures, they found, performed with 93% sensitivity and 18% PPV for CIN3, comparable to the combination of cytology and HPV genotyping (86% sensitivity and 19% PPV).
High‐risk human papillomavirus (hrHPV) DNA tests have excellent sensitivity for detection of cervical intraepithelial neoplasia 2 or higher (CIN2+). A drawback of hrHPV screening, however, is modest ...specificity. Therefore, hrHPV‐positive women might need triage to reduce adverse events and costs associated with unnecessary colposcopy. We compared the performance of HPV16/18 genotyping with a predefined DNA methylation triage test (S5) based on target regions of the human gene EPB41L3, and viral late gene regions of HPV16, HPV18, HPV31 and HPV33. Assays were run using exfoliated cervical specimens from 710 women attending routine screening, of whom 38 were diagnosed with CIN2+ within a year after triage to colposcopy based on cytology and 341 were hrHPV positive. Sensitivity and specificity of the investigated triage methods were compared by McNemar's test. At the predefined cutoff, S5 showed better sensitivity than HPV16/18 genotyping (74% vs 54%, P = 0.04) in identifying CIN2+ in hrHPV‐positive women, and similar specificity (65% vs 71%, P = 0.07). When the S5 cutoff was altered to allow equal sensitivity to that of genotyping, a significantly higher specificity of 91% was reached (P < 0.0001). Thus, a DNA methylation test for the triage of hrHPV‐positive women on original screening specimens might be a valid approach with better performance than genotyping.
What's new?
DNA testing for high‐risk human papillomaviruses (hrHPVs) can both detect and predict the development of precancerous cervical lesions. Limitations in specificity, however, necessitate the generation of triage strategies to minimize unneeded colposcopy among hrHPV‐positive women. According to this study, triage may be readily affected using a DNA methylation classifier based on the human gene EPB41L3 and the late gene regions of HPV16, HPV18, HPV31 and HPV33. The devised classifier outperformed triage by HPV16/18 genotyping in a cohort of hrHPV‐positive patients. The strategy could fill a key role in hrHPV triage in cervical screening programs.
Purpose At least 94 common single nucleotide polymorphisms (SNPs) are associated with breast cancer. The extent to which an SNP panel can refine risk in women who receive preventive therapy has not ...been directly assessed previously. Materials and Methods A risk score on the basis of 88 SNPs (SNP88) was investigated in a nested case-control study of women enrolled in the International Breast Intervention Study (IBIS-I) or the Royal Marsden study. A total of 359 women who developed cancer were matched to 636 controls by age, trial, follow-up time, and treatment arm. Genotyping was done using the OncoArray. Conditional logistic regression and matched concordance indices (mC) were used to measure the performance of SNP88 alone and with other breast cancer risk factors assessed using the Tyrer-Cuzick (TC) model. Results SNP88 was predictive of breast cancer risk overall (interquartile range odds ratio IQ-OR, 1.37; 95% CI, 1.14 to 1.66; mC, 0.55), but mainly for estrogen receptor-positive disease (IQ-OR, 1.44; 95% CI, 1.16 to 1.79; P for heterogeneity = .10) versus estrogen receptor-negative disease. However, the observed risk of SNP88 was only 46% (95% CI, 19% to 74%) of expected. No significant interaction was observed with treatment arm (placebo IQ-OR, 1.46; 95% CI, 1.13 to 1.87; tamoxifen IQ-OR, 1.25; 95% CI, 0.96 to 1.64; P for heterogeneity = .5). The predictive power was similar to the TC model (IQ-OR, 1.45; 95% CI, 1.21 to 1.73; mC, 0.55), but SNP88 was independent of TC (Spearman rank-order correlation, 0.012; P = .7), and when combined multiplicatively, a substantial improvement was seen (IQ-OR, 1.64; 95% CI, 1.36 to 1.97; mC, 0.60). Conclusion A polygenic risk score may be used to refine risk from the TC or similar models in women who are at an elevated risk of breast cancer and considering preventive therapy. Recalibration may be necessary for accurate risk assessment.
The evolution of precancerous cervical lesions is poorly understood. A widely held model of cervical intraepithelial neoplasia grade 3 (CIN3) development is sequential progression from normal through ...CIN1 and CIN2 to CIN3. Another hypothesis, the “molecular switch” model, postulates that CIN3 can evolve directly from human papillomavirus (HPV)‐infected normal epithelium without progressing through CIN1 and CIN2. To shed light on this process, we compared DNA methylation of selected human biomarkers and HPV types in two groups of CIN1: CIN1 that were near or adjacent to CIN3 (adjacent‐CIN1) and CIN1 that were the principal lesions with no CIN3 detected (principal‐CIN1). 354 CIN (CIN1 and CIN3) and normal tissue areas were dissected and typed for HPV from 127 women who underwent loop electrosurgical excision procedures (LEEP). Methylation of genes EPB41L3 and the viral regions of HPV16‐L1/L2, HPV18‐L2, HPV31‐L1, and HPV33‐L2 were determined by a highly accurate quantitative pyrosequencing of bisulfite converted DNA. There was a significant trend of increased methylation with disease grade comparing normal to CIN1 and CIN3 (p < 0.0001). Adjacent‐CIN1 predominantly shared the same HPV types as the CIN3, however, methylation differed substantially between adjacent‐CIN1 and CIN3 (p = 0.008). In contrast diagnostically principal‐CIN1 had an indistinguishable methylation distribution compared to adjacent‐CIN1 (EPB41L3: p = 0.49; HPVme‐All: p = 0.11). Our results suggest that progression from normal epithelium to CIN1 or CIN3 is usually promoted by the same HPV type but occurs via distinct DNA epigenotypes, thus favoring the “molecular switch” model.
What's new?
Do cervical intraepithelial neoplasias always start at CIN1 and progress to CIN3? Or can CIN3 arise directly from normal epithelium, after HPV infection? The authors investigated by testing DNA methylation in different CINs. They compared CIN1 with CIN3 within the same cervix, and also compared CIN1 adjacent to CIN3 with CIN1 from patients without detectable CIN3. CIN1 and their neighboring CIN3, they found, each had distinct patterns of methylation, despite carrying the same HPV infection. All the CIN1 samples, however, exhibited similar methylation, regardless of the presence of CIN3. This suggests methylation can switch cells directly into a CIN3 state.
Implementing matrix-assisted laser desorption ionization-time of flight and multiplex polymerase chain reaction has been associated with decreased mortality and hospital length of stay in adults, but ...the impact in pediatrics is less understood.
This pre-post quasi-experimental study compared antibiotic prescribing for positive blood cultures in patients ≤21 years of age collected in 2012 (preintervention) and in 2015 (after matrix-assisted laser desorption ionization-time of flight/multiplex polymerase chain reaction). Time to effective and optimal antimicrobial therapy was evaluated using Cox proportional hazards regression. Time to ideal optimal therapy was estimated as the earliest potential initiation of optimal therapy. Antibiotic use and clinical outcomes were measured.
There were 242 and 192 positive monomicrobial blood cultures in 2012 and 2015, respectively. Postintervention, time to optimal therapy (73.8 vs. 48.8 hours; P < 0.001) and organism identification (55.6 vs. 29.5 hours; P < 0.001) were reduced, and patients were more likely to receive optimal therapy by 7 days (hazard ratio, 1.85; P < 0.001). In the ideal scenario in 2015, there was an 8.8-hour delay in initiating optimal therapy based on the time that sufficient microbiologic data were available. Postintervention, time to effective therapy (2.8 vs. 2.7 hours; P = 0.782) and clinical outcomes did not differ. Unnecessary antibiotic duration for probable contaminants (skin flora) (43.1 vs. 29.7 hours; P = 0.027), vancomycin for methicillin-sensitive Staphylococcus aureus (54.0 vs. 41.3 hours; P = 0.008) and nonpenicillin/ampicillin antibiotics for group A Streptococcus, group B Streptococcus and Enterococcus faecalis (87.2 vs. 33.4 hours; P < 0.001) were reduced postintervention.
Rapid diagnostics reduced time to optimal antimicrobial therapy and unnecessary antibiotic use without worse clinical outcomes.
Methylation biomarkers are promising tools for diagnosis and disease prevention. The S5 classifier is aimed at the prevention of cervical cancer by the early detection of cervical intraepithelial ...neoplasia (CIN). S5 is based on pyrosequencing a promoter region of EPB41L3 and five late regions of HPV types 16, 18, 31, and 33 following bisulfite conversion of DNA. Good biomarkers should perform well in a variety of sample types such as exfoliated cells, fresh frozen or formalin‐fixed paraffin‐embedded (FFPE) materials. Here, we tested the performance of S5 on 315 FFPE biopsies with paired exfoliated cervical samples using four different conversion kits (Epitect Bisulfite, Epitect Fast Bisulfite, EZ DNA Methylation, and EZ DNA Methylation‐Lightning). The S5 values from FFPE biopsies for all kits were significantly correlated with those obtained from their paired exfoliated cells. For the EZ DNA Methylation kit, we observed an average increased methylation of 4.4% in FFPE. This was due to incomplete conversion of DNA (73% for FFPE vs. 95% for cells). The other kits had a DNA conversion rate in FFPE similar to the cells (95%–97%). S5 performed well at discriminating <CIN2 lesions from CIN2+ lesions on the FFPE with all kits given optimized adjustments to the cut‐off. The area under the curve (AUC) for S5 on FFPE was not significantly different from the paired cells (0.74–0.79 vs. 0.81). The best sensitivity and specificity were obtained for EZ DNA Methylation after the adjustment of the cut‐off to reflect its lower conversion rate. Consistent methylation results can be obtained from FFPE material regardless of the conversion kit used. The S5 classifier performed as well on FFPE material as on exfoliated cells with adjusted cut‐off allowing easier clinical implementation.
The S5 Classifier is a DNA methylation‐based assay designed to detect pre‐cancerous cervical tissue. It was designed using a particular bisulfite conversion kit and optimized on fresh cells only. In this study, we establish that the S5 Classifier works to a similar level of sensitivity and specificity in FFPE tissue as it does in exfoliated samples and with three other bisulfite conversion kits. This validates its validity as an effective biomarker assay.
Visual interpretation of cervical biopsies is subjective and variable, generally showing fair to moderate inter‐reader agreement in distinguishing high from low grade cervical intraepithelial ...neoplasia (CIN). We investigated the performance of two objective p16 quantitative tests in comparison with visual assessment: (i) p16‐mRNA assay and (ii) digital analysis of sections stained for p16 protein. The primary analysis considered 232 high‐risk human papilloma virus positive (HPV+) samples from diagnostic cervical specimens. A p16 RT‐qPCR (p16‐mRNA assay) was run on mRNA extracted from formalin‐fixed paraffin‐embedded sections. Two p16 immunohistochemistry (IHC) readings, a visual read by a histopathologist (Visual IHC) and a digital read of a high‐resolution scan (Digital IHC), were done on adjacent sections. The worst reviewed CIN grade (agreed by at least two histopathologists) from up to two biopsies and a loop excision was taken, with CIN2/3 as the primary endpoint. Visual IHC attained a specificity of 70% (95%CI 61–77) for 85% (95%CI 77–91%) sensitivity. The four‐point Visual IHC staining area under the curve (AUC) was 0.77 (95%CI 0.71–0.82), compared with 0.71 (95%CI 0.64–0.77) for p16‐mRNA and 0.67 (95%CI 0.60–0.74) for Digital IHC. Spearman rank‐order correlations were: visual to p16‐mRNA 0.41, visual to digital 0.49 and p16‐mRNA to digital: 0.22. The addition of p16‐mRNA assay to visual reading of p16 IHC improved the AUC from 0.77 to 0.84 (p = 0.0049). p16‐mRNA testing may be complementary to visual IHC p16 staining for a more accurate diagnosis of CIN, or perhaps a substitute in locations with a lack of skilled pathologists.
What's new?
Visual examination of cervical tissue obtained by biopsy provides information on morphological changes associated with human papillomavirus (HPV) infection and transformation to precancerous cervical intraepithelial neoplasia 2/3 (CIN2/3). The accuracy of CIN2/3 diagnosis by visual interpretation, however, could be improved through the use of complementary objective tests. This study describes two such tests: quantitative p16 mRNA analysis and digital analysis of immunohistochemical p16‐protein staining. CIN2/3 diagnostic accuracy benefitted especially from the addition of p16‐mRNA testing. Both new approaches could prove useful in locations lacking trained pathologists and could help avoid overtreatment in HPV‐positive women, many of whom recover spontaneously.
Background
Prompt central venous catheter (CVC) removal is currently recommended in children with
Staphylococcus aureus
central line-associated bloodstream infection (CLABSI). Our objective was to ...examine the outcome of attempted line salvage in children with
S. aureus
CLABSI and assess predictors of success.
Methods
A single-institution, retrospective cohort study was performed of all children with
S. aureus
CLABSI between 2012 and 2015. Patients with and without immediate CVC removal (≤ 2 days after first positive culture) were compared. The primary outcome was failed CVC salvage (removal after 3+ days).
Results
Seventy-seven children met criteria for
S. aureus
CLABSI. Immediate CVC removal was performed in 27.3% of patients. Among the 72.7% patients in whom CVC salvage was attempted, 78.6% were successful and 21.4% required delayed CVC removal. Malignancy, short gut syndrome, neutropenia, methicillin-resistant
S. aureus
, and line type were not associated with salvage failure. No associated morbidity or mortality occurred in patients with a failed salvage attempt. New or recurrent bacteremia occurred in five patients, but three were successfully salvaged a second time.
Conclusions
CVC salvage was feasible in the majority of children with
S. aureus
CLABSI and was not associated with significant complications or attributable mortality as reported in adults.
Clinal variation in quantitative traits is widespread, but its genetic basis awaits identification. Drosophila melanogaster shows adaptive, clinal variation in traits such as body size along ...latitudinal gradients on multiple continents. To investigate genome wide transcription differentiation between North and South that might contribute to the clinal phenotypic variation, we compared RNA expression patterns during development of D. melanogaster from tropical northern and temperate southern populations using whole genome tiling arrays. We found that genes that were differentially expressed between the cline ends were generally associated with metabolism and growth, and experimental alteration of expression of a sample of them generally resulted in altered body size in the predicted direction, sometimes significantly so. We further identified the serpent (srp) transcription factor binding sites to be enriched near genes up-regulated in expression in the south. Analysis of clinal populations revealed a significant cline in the expression level of srp. Experimental over-expression of srp increased body size, as predicted from its clinal expression pattern, suggesting that it may be involved in regulating adaptive clinal variation in Drosophila. This study identified a handful of genes that contributed to clinal phenotypic variation through altered gene expression level, yet misexpression of individual gene led to modest body size change.
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