Impact of improved classification on the association of human papillomavirus with cervical precancer

Relationships of p16 Immunohistochemistry and Other Biomarkers With Diagnoses of Cervical Abnormalities: Implications for LAST Terminology

CONTEXT.—

Lower Anogenital Squamous Terminology (LAST) standardization recommended p16INK4a immunohistochemistry (p16 IHC) for biopsies diagnosed morphologically as cervical intraepithelial neoplasia (CIN) grade 2 (CIN2) to classify them as low-grade or high-grade squamous intraepithelial lesions (HSILs).

OBJECTIVE.—

To describe the relationships of p16 IHC and other biomarkers associated with cervical cancer risk with biopsy diagnoses.

DESIGN.—

A statewide, stratified sample of cervical biopsies diagnosed by community pathologists (CPs), including 1512 CIN2, underwent a consensus, expert pathologist panel (EP) review (without p16 IHC results), p16 IHC interpretation by a third pathology group, and human papillomavirus (HPV) genotyping, results of which were grouped hierarchically according to cancer risk. Antecedent cytologic interpretations were also available.

RESULTS.—

Biopsies were more likely to test p16 IHC positive with increasing severity of CP diagnoses, overall (Ptrend ≤ .001) and within each HPV risk group (Ptrend ≤ .001 except for low-risk HPV [Ptrend < .010]). All abnormal grades of CP-diagnosed biopsies were more likely to test p16 IHC positive with a higher HPV risk group (Ptrend < .001), and testing p16 IHC positive was associated with higher HPV risk group than testing p16 IHC negative for each grade of CP-diagnosed biopsies (P < .001). p16 IHC-positive, CP-diagnosed CIN2 biopsies were less likely than CP-diagnosed CIN3 biopsies to test HPV16 positive, have an antecedent HSIL+ cytology, or to be diagnosed as CIN3+ by the EP (P < .001 for all). p16 IHC-positive, CP-diagnosed CIN1 biopsies had lower HPV risk groups than p16 IHC-negative, CP-diagnosed CIN2 biopsies (P < .001).

CONCLUSIONS.—

p16 IHC-positive, CP-diagnosed CIN2 appears to be lower cancer risk than CP-diagnosed CIN3. LAST classification of "HSIL" diagnosis, which includes p16 IHC-positive CIN2, should annotate the morphologic diagnosis (CIN2 or CIN3) to inform all management decisions, which is especially important for young (<30 years) women diagnosed with CIN2 for whom surveillance rather than treatment is recommended.

Methylation estimates the risk of precancer in HPV-infected women with discrepant results between cytology and HPV16/18 genotyping

BACKGROUND

Vigilant management of women with high-risk human papillomavirus (hrHPV) is necessary in cancer screening programs. To this end, we evaluated the performance of S5 (targeting DNA methylation in HPV16, HPV18, HPV31, HPV33, and human gene EPB41L3) to predict cervical intraepithelial neoplasia grade 2 or higher (CIN2+) in a sample of hrHPV-infected women referred to colposcopy in the FRIDA Study, a large screening trial in Mexico. A nested case-control sample with women referred to colposcopy either by atypical squamous cells of undetermined significance or higher (ASCUS+) in cytology and/or positive for HPV types 16 or 18 was tested by S5. Seventy-nine cases of CIN2+ were age-matched to 237 controls without a diagnosis of CIN2+ (

RESULTS

The S5 classifier separated women with CIN2+ from

CONCLUSIONS

S5 testing on hrHPV-positive women significantly increased diagnostic information compared to triage by HPV16/18 plus cytology and appears to have clinical utility as an additional test to substantially lessen burdens on colposcopy.

TRIAL REGISTRATION

The FRIDA Study is registered in ClinicalTrials.gov , number NCT02510027.

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Key Words

• Cervical cancer
• Cervical intraepithelial neoplasia
• DNA methylation
• EPB41L3
• Human papillomavirus
• S5 classifier
• Triage

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MESH Headings

• Adult
• Area Under Curve
• Case-Control Studies
• Clinical Trials as Topic
• Colposcopy
• DNA Methylation
• DNA, Viral/genetics
• Early Detection of Cancer/methods
• Epigenesis, Genetic
• Female
• Genotype
• Human papillomavirus 16/genetics
• Human papillomavirus 18/genetics
• Humans
• Mexico
• Microfilament Proteins/genetics
• Middle Aged
• Papillomavirus Infections/complications
• Papillomavirus Infections/genetics
• Sensitivity and Specificity
• Sequence Analysis, DNA
• Triage
• Uterine Cervical Neoplasms/diagnosis
• Uterine Cervical Neoplasms/genetics
• Uterine Cervical Neoplasms/virology
• Uterine Cervical Dysplasia/diagnosis
• Uterine Cervical Dysplasia/genetics
• Uterine Cervical Dysplasia/virology

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Grants

• 21070 Cancer Research UK
• 27046 Cancer Research UK
• P30 CA016672 NCI NIH HHS
• C569/A10404 Cancer Research UK
• Instituto Mexicano del Seguro Social
• Secretaría de Salud
• Consejo Nacional de Ciencia y Tecnología
• Instituto Nacional de Salud Publica

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Affiliation(s)

Rubí Hernández-López Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México Centro de Investigación en Políticas, Población y Salud, Universidad Nacional Autónoma, Ciudad de México, México
Attila T. Lorincz Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Leticia Torres-Ibarra Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México
Caroline Reuter Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Dorota Scibior-Bentkowska Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Rhian Warman Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Belinda Nedjai Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Indira Mendiola-Pastrana Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México
Leith León-Maldonado Centro de Investigación en Políticas, Población y Salud, Universidad Nacional Autónoma, Ciudad de México, México Cátedra-CONACYT, Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México
Berenice Rivera-Paredez Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México Centro de Investigación en Políticas, Población y Salud, Universidad Nacional Autónoma, Ciudad de México, México
Paula Ramírez-Palacios Unidad de Investigación Epidemiológica y en Servicios de Salud, Delegación Morelos, Instituto Mexicano del Seguro Social, Cuernavaca, Morelos México
Eduardo Lazcano-Ponce Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos México
Jack Cuzick Wolfson Institute of Preventive Medicine, Centre for Cancer Prevention, Queen Mary University of London, London, UK
Jorge Salmerón Centro de Investigación en Políticas, Población y Salud, Universidad Nacional Autónoma, Ciudad de México, México

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Molecular progression to cervical precancer, epigenetic switch or sequential model?

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.

Cytology versus HPV testing for cervical cancer screening in the general population

BACKGROUND

Cervical cancer screening has traditionally been based on cervical cytology. Given the aetiological relationship between human papillomavirus (HPV) infection and cervical carcinogenesis, HPV testing has been proposed as an alternative screening test.

OBJECTIVES

To determine the diagnostic accuracy of HPV testing for detecting histologically confirmed cervical intraepithelial neoplasias (CIN) of grade 2 or worse (CIN 2+), including adenocarcinoma in situ, in women participating in primary cervical cancer screening; and how it compares to the accuracy of cytological testing (liquid-based and conventional) at various thresholds.

SEARCH METHODS

We performed a systematic literature search of articles in MEDLINE and Embase (1992 to November 2015) containing quantitative data and handsearched the reference lists of retrieved articles.

SELECTION CRITERIA

We included comparative test accuracy studies if all women received both HPV testing and cervical cytology followed by verification of the disease status with the reference standard, if positive for at least one screening test. The studies had to include women participating in a cervical cancer screening programme who were not being followed up for previous cytological abnormalities.

DATA COLLECTION AND ANALYSIS

We completed a 2 x 2 table with the number of true positives (TP), false positives (FP), true negatives (TN), and false negatives for each screening test (HPV test and cytology) used in each study. We calculated the absolute and relative sensitivities and the specificities of the tests for the detection of CIN 2+ and CIN 3+ at various thresholds and computed sensitivity (TP/(TP + TN) and specificity (TN/ (TN + FP) for each test separately. Relative sensitivity and specificity of one test compared to another test were defined as sensitivity of test-1 over sensitivity of test-2 and specificity of test-1 over specificity of test-2, respectively. To assess bias in the studies, we used the Quality Assessment of Diagnostic test Accuracy Studies (QUADAS) tool. We used a bivariate random-effects model for computing pooled accuracy estimates. This model takes into account the within- and between-study variability and the intrinsic correlation between sensitivity and specificity.

MAIN RESULTS

We included a total of 40 studies in the review, with more than 140,000 women aged between 20 and 70 years old. Many studies were at low risk of bias. There were a sufficient number of included studies with adequate methodology to perform the following test comparisons: hybrid capture 2 (HC2) (1 pg/mL threshold) versus conventional cytology (CC) (atypical squamous cells of undetermined significance (ASCUS)+ and low-grade squamous intraepithelial lesions (LSIL)+ thresholds) or liquid-based cytology (LBC) (ASCUS+ and LSIL+ thresholds), other high-risk HPV tests versus conventional cytology (ASCUS+ and LSIL+ thresholds) or LBC (ASCUS+ and LSIL+ thresholds). For CIN 2+, pooled sensitivity estimates for HC2, CC and LBC (ASCUS+) were 89.9%, 62.5% and 72.9%, respectively, and pooled specificity estimates were 89.9%, 96.6%, and 90.3%, respectively. The results did not differ by age of women (less than or greater than 30 years old), or in studies with verification bias. Accuracy of HC2 was, however, greater in European countries compared to other countries. The results for the sensitivity of the tests were heterogeneous ranging from 52% to 94% for LBC, and 61% to 100% for HC2. Overall, the quality of the evidence for the sensitivity of the tests was moderate, and high for the specificity.The relative sensitivity of HC2 versus CC for CIN 2+ was 1.52 (95% CI: 1.24 to 1.86) and the relative specificity 0.94 (95% CI: 0.92 to 0.96), and versus LBC for CIN 2+ was 1.18 (95% CI: 1.10 to 1.26) and the relative specificity 0.96 (95% CI: 0.95 to 0.97). The relative sensitivity of HC2 versus CC for CIN 3+ was 1.46 (95% CI: 1.12 to 1.91) and the relative specificity 0.95 (95% CI: 0.93 to 0.97). The relative sensitivity of HC2 versus LBC for CIN 3+ was 1.17 (95% CI: 1.07 to 1.28) and the relative specificity 0.96 (95% CI: 0.95 to 0.97).

AUTHORS' CONCLUSIONS

Whilst HPV tests are less likely to miss cases of CIN 2+ and CIN 3+, these tests do lead to more unnecessary referrals. However, a negative HPV test is more reassuring than a negative cytological test, as the cytological test has a greater chance of being falsely negative, which could lead to delays in receiving the appropriate treatment. Evidence from prospective longitudinal studies is needed to establish the relative clinical implications of these tests.

Commercially available molecular tests for human papillomaviruses (HPV): 2015 update

Commercial molecular tests for human papillomaviruses (HPV) are invaluable diagnostic tools in cervical carcinoma screening and management of women with cervical precancerous lesions as well as important research tools for epidemiological studies, vaccine development, and implementation and monitoring of vaccination programs. In this third inventory of commercial HPV tests, we identified 193 distinct commercial HPV tests and at least 127 test variants available on the market in 2015, which represents a 54% and 79% increase in the number of distinct HPV tests and variants, respectively, in comparison to our last inventory performed in 2012. Identified HPV tests were provisionally divided into eight main groups and several subgroups. Among the 193 commercial HPV tests, all but two target alpha-HPV types only. Although the number of commercial HPV tests with at least one published study in peer-reviewed literature has increased significantly in the last three years, several published performance evaluations are still not in line with agreed-upon standards in the HPV community. Manufacturers should invest greater effort into evaluating their products and publishing validation/evaluation results in peer-reviewed journals. To achieve this, more clinically oriented external quality-control panels and initiatives are required. For evaluating the analytical performance of the entire range of HPV tests currently on the market, more diverse and reliable external quality-control programs based on international standards for all important HPV types are indispensable. The performance of a wider range of HPV tests must be promptly evaluated on a variety of alternative clinical specimens. In addition, more complete HPV assays containing validated sample-extraction protocols and appropriate internal controls are urgently needed. Provision of a broader range of automated systems allowing large-scale HPV testing as well as the development of reliable, rapid, and affordable molecular point-of-care tests are priorities for the further improvement of HPV tests.

Methylation analysis of the FAM19A4 gene in cervical scrapes is highly efficient in detecting cervical carcinomas and advanced CIN2/3 lesions

Primary testing for human papillomavirus (HPV) in cervical screening requires triage to differentiate women with transient infection from those with persistent infection who require more intensive management given their risk for cervical (pre)cancer. In this study, the clinical performance of a novel methylation marker FAM19A4 for the triage of high-risk (hr)HPV-positive women was evaluated. Using a training-validation set approach, we analyzed a FAM19A4 quantitative methylation-specific PCR (qMSP). The training set comprised hrHPV-positive cervical scrapes of 43 women with cervical intraepithelial neoplasia grade 3 or worse (CIN3+) and 135 women with ≤CIN1. The validation set comprised hrHPV-positive cervical scrapes of 52 women with CIN2+, including 33 CIN3+, 19 CIN2, and 166 women with ≤CIN1. The methylation threshold of FAM19A4 qMSP that gave rise to CIN3+ specificity of 70% in the training set was applied in the validation set. This resulted in CIN3+ sensitivity of 75.8% [95% confidence interval (CI), 61.1-90.4] at 67.0% (95% CI, 60.3-73.8) specificity. Next, the validated qMSP was applied to an independent series of hrHPV-positive cervical scrapes of 22 women with cervical cancer, 29 with advanced CIN2/3 [i.e., women with a known preceding hrHPV infection (PHI) lasting ≥5 years as proxy of longer duration of lesion existence], and 19 with early CIN2/3 (i.e., PHI <5 years). All carcinomas (22/22) and advanced CIN2/3 lesions (29/29) were FAM19A4 methylation-positive, compared with 42.1% (8/19; 95% CI, 19.9-64.3) of early CIN2/3 lesions. In conclusion, FAM19A4 is an attractive triage marker for hrHPV-positive women, with a high reassurance for the detection of cervical carcinoma and advanced CIN2/3 lesions.

Immunohistochemical expression of p16 and HPV L1 capsid proteins as predictive markers in cervical lesions

PURPOSE

Human papilloma virus (HPV) infection is the most important cause of cervical cancer, but only 2 % of cervical HPV infections will develop into cervical cancer. p16 INK4A has been introduced as a marker for HPV infection in cervix. HPV L1 capsid protein is also known to be associated with the productive phase of HPV infection; however, expression pattern in different HPV-associated cervical lesion and its correlation to p16 expression is not still well understood. The authors aimed to elucidate the relationship between L1 and p16 expression in cervical lesions.

METHODS

Immunohistochemical studies using antibodies against L1 capsid and P16 proteins were carried out on 89 paraffin-embedded tissue samples including 11 low-grade cervical intraepithelial neoplasias (CIN), 11 high-grade CINs, 20 cervical squamous cell carcinomas (SCC), eight cervical adenocarcinomas and 39 normal cervical tissues as a control group.

RESULTS

L1 capsid protein was positive in 63.6 % of low-grade CINs and 9.1 % of high-grade CINs; while none of the cervical SCCs, adenocarcinomas or normal cervical tissues showed this marker. In contrast, p16 protein was positive in 81.8 % of low-grade CINs, 90.1 % of high-grade CINs, 90 % of SCCs, 75 % of adenocarcinomas and 10.25 % of normal cervical tissues (p value < 0.001).

CONCLUSION

Despite the presence of interobserver variation in the histopathologic interpretation of cervical lesions, in more instances definite diagnosis is made by routine histopathological examination and these ancillary tests are supportive in follow-up of the patient.

Nucleic acid tests for the detection of alpha human papillomaviruses

Testing for high-risk types of alpha human papillomaviruses (HPV) is an invaluable part of clinical guidelines for cervical carcinoma screening, management and treatment. In this comprehensive inventory of commercial tests for detection of alpha-HPV, we identified at least 125 distinct HPV tests and at least 84 variants of the original tests. However, only a small subset of HPV tests has documented clinical performance for any of the standard HPV testing indications. For more than 75% of HPV tests currently on the market, no single publication in peer-reviewed literature can be identified. HPV tests that have not been validated and lack proof of reliability, reproducibility and accuracy should not be used in clinical management. Once incorporated in the lab, it is essential that the whole procedure of HPV testing is subject to continuous and rigorous quality assurance to avoid sub-optimal, potentially harmful practices. Manufacturers of HPV tests are urged to put more effort into evaluating their current and future products analytically, using international standards, and for clinical applications, using clinically validated endpoints. To assist with analytical validation, the World Health Organization is developing international standards for HPV types other than HPV16 and HPV18 and is planning development of external quality control panels specifically designed to be used for performance evaluation of current and future HPV tests. There is a need for more competitively priced HPV tests, especially for resource-poor countries, and uniform test validation criteria based on international standards should enable issuing more competitive and fair tender notices for purchasing. Automation systems allowing large-scale testing, as well as further increases in clinical performance, are the main needs in the further improvement of HPV tests. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Human papillomavirus testing versus repeat cytology for triage of minor cytological cervical lesions

BACKGROUND

Atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intra-epithelial lesions (LSIL) are minor lesions of the cervical epithelium, detectable by cytological examination of cells collected from the surface of the cervix of a woman.Usually, women with ASCUS and LSIL do not have cervical (pre-) cancer, however a substantial proportion of them do have underlying high-grade cervical intra-epithelial neoplasia (CIN, grade 2 or 3) and so are at increased risk for developing cervical cancer. Therefore, accurate triage of women with ASCUS or LSIL is required to identify those who need further management.This review evaluates two ways to triage women with ASCUS or LSIL: repeating the cytological test, and DNA testing for high-risk types of the human papillomavirus (hrHPV) - the main causal factor of cervical cancer.

OBJECTIVES

Main objective To compare the accuracy of hrHPV testing with the Hybrid Capture 2 (HC2) assay against that of repeat cytology for detection of underlying cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) or grade 3 or worse (CIN3+) in women with ASCUS or LSIL. For the HC2 assay, a positive result was defined as proposed by the manufacturer. For repeat cytology, different cut-offs were used to define positivity: Atypical squamous cells of undetermined significance or worse (ASCUS+), low-grade squamous intra-epithelial lesions or worse (LSIL+) or high-grade squamous intra-epithelial lesions or worse (HSIL+).Secondary objective To assess the accuracy of the HC2 assay to detect CIN2+ or CIN3+ in women with ASCUS or LSIL in a larger group of reports of studies that applied hrHPV testing and the reference standard (coloscopy and biopsy), irrespective whether or not repeat cytology was done.

SEARCH METHODS

We made a comprehensive literature search that included the Cochrane Register of Diagnostic Test Accuracy Studies; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE (through PubMed), and EMBASE (last search 6 January 2011). Selected journals likely to contain relevant papers were handsearched from 1992 to 2010 (December). We also searched CERVIX, the bibliographic database of the Unit of Cancer Epidemiology at the Scientific Institute of Public Health (Brussels, Belgium) which contains more than 20,000 references on cervical cancer.More recent searches, up to December 2012, targeted reports on the accuracy of triage of ASCUS or LSIL with other HPV DNA assays, or HPV RNA assays and other molecular markers. These searches will be used for new Cochrane reviews as well as for updates of the current review.

SELECTION CRITERIA

Studies eligible for inclusion in the review had to include: women presenting with a cervical cytology result of ASCUS or LSIL, who had undergone both HC2 testing and repeat cytology, or HC2 testing alone, and were subsequently subjected to reference standard verification with colposcopy and colposcopy-directed biopsies for histologic verification.

DATA COLLECTION AND ANALYSIS

The review authors independently extracted data from the selected studies, and obtained additional data from report authors.Two groups of meta-analyses were performed: group I concerned triage of women with ASCUS, group II concerned women with LSIL. The bivariate model (METADAS-macro in SAS) was used to assess the absolute accuracy of the triage tests in both groups as well as the differences in accuracy between the triage tests.

MAIN RESULTS

The pooled sensitivity of HC2 was significantly higher than that of repeat cytology at cut-off ASCUS+ to detect CIN2+ in both triage of ASCUS and LSIL (relative sensitivity of 1.27 (95% CI 1.16 to 1.39; P value < 0.0001) and 1.23 (95% CI 1.06 to 1.4; P value 0.007), respectively. In ASCUS triage, the pooled specificity of the triage methods did not differ significantly from each other (relative specificity: 0.99 (95% CI 0.97 to 1.03; P value 0.98)). However, the specificity of HC2 was substantially, and significantly, lower than that of repeat cytology in the triage of LSIL (relative specificity: 0.66 (95% CI 0.58 to 0.75) P value < 0.0001).

AUTHORS' CONCLUSIONS

HPV-triage with HC2 can be recommended to triage women with ASCUS because it has higher accuracy (significantly higher sensitivity, and similar specificity) than repeat cytology. When triaging women with LSIL, an HC2 test yields a significantly higher sensitivity, but a significantly lower specificity, compared to a repeat cytology. Therefore, practice recommendations for management of women with LSIL should be balanced, taking local circumstances into account.

HPV vaccines and cancer prevention, science versus activism

The rationale behind current worldwide human papilloma virus (HPV) vaccination programs starts from two basic premises, 1) that HPV vaccines will prevent cervical cancers and save lives and, 2) have no risk of serious side effects. Therefore, efforts should be made to get as many pre-adolescent girls vaccinated in order to decrease the burden of cervical cancer. Careful analysis of HPV vaccine pre- and post-licensure data shows however that both of these premises are at odds with factual evidence and are largely derived from significant misinterpretation of available data.

The detection of hTERC amplification using fluorescence in situ hybridization in the diagnosis and prognosis of cervical intraepithelial neoplasia: a case control study

Background

Currently the routine non-invasive screening methods for cervical intraepithelial neoplasia (CIN) and cervical cancer are Thinprep cytology test (TCT) and human papillomavirus testing. However, both methods are limited by the high false positive and false negative rates and lack of association with patients’ prognosis, especially for the early detection of pro-malignant CIN. The aim of the study was to investigate the role of genomic amplification of human telomerase gene (hTERC) in the diagnosis and prognosis of CIN.

Methods

The study group consisted of specimens of exfoliated cervical cells from 151 patients, including 27 with CIN I, 54 with CIN II/III, 17 with carcinoma in situ, and 28 with invasive squamous carcinoma, as well as 25 patients who were at 2-year follow-up after either Loop Electrosurgical Excision treatment (n = 11) or radical surgery (n = 14). hTERC amplification was detected by dual-color interphase fluorescence in situ hybridization (FISH), and the results were compared with TCT and histologic examination. The final diagnosis was determined by the pathological examination. The control group consisted of specimens of exfoliated cervical cells from 40 normal women.

Results

The percentage of cervical exfoliated cells with positive hTERC amplification and incidence rates of hTERC amplification were 9.2% ± 4.6% and 44.4% (12/27) respectively in patients with CIN I; 16.0% ± 14.4% and 85.1% (46/54) in patients with CIN II/III; 19.7% ± 13.3% and 88.3% (15 /17) in patients with carcinoma in situ; 47.0% ± 25.2% and 100% (28/28)in patients with invasive squamous carcinoma. There was statistically significant difference between the control and study group (P <0.01), and between the patients with various diseases within the study group (P <0.05).

Conclusion

The detection of genomic amplification of hTERC using FISH is a non-invasive and effective approach for CIN.

3q26 amplification is an effective negative triage test for LSIL: a historical prospective study

Background

Women with low grade squamous intraepithelial lesions (LSIL) at cervical cancer screening are currently referred for further diagnostic work up despite 80% having no precancerous lesion. The primary purpose of this study is to measure the test characteristics of 3q26 chromosome gain (3q26 gain) as a host marker of carcinogenesis in women with LSIL. A negative triage test may allow these women to be followed by cytology alone without immediate referral to colposcopy.

Methods and Findings

A historical prospective study was designed to measure 3q26 gain from the archived liquid cytology specimens diagnosed as LSIL among women attending colposcopy between 2007 and 2009. 3q26 gain was assessed on the index liquid sample; and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were measured at immediate triage and at 6–16 months after colposcopic biopsy. The sensitivity of 3q26 gain measured at immediate triage from automated and manually reviewed tests in 65 non-pregnant unique women was 70% (95% CI: 35, 93) with a NPV of 89% (95% CI: 78, 96). The sensitivity and NPV increased to 80% (95% CI: 28, 99) and 98% (95% CI: 87, 100), respectively, when only the automated method of detecting 3q26 gain was used.

Conclusions

3q26 gain demonstrates high sensitivity and NPV as a negative triage test for women with LSIL, allowing possible guideline changes to routine surveillance instead of immediate colposcopy. Prospective studies are ongoing to establish the sensitivity, specificity, PPV and NPV of 3q26 gain for LSIL over time.

Next Generation Cancer Protection: The Bivalent HPV Vaccine for Females

Nearly a half a million women throughout the world develop cervical cancer every year Parkin and Bray ("Chapter 2. The burden of HPVrelated cancers," Vaccine, vol. 24, no. 3, pp. S11-S25, 2006); 80% of these women are in countries without a quality-assured cytology screening program. It is in this setting that Cervarix could reduce the incidence of cervical cancer to about 9.5/100,000 women. New evidence indicates that this might be able to be accomplished with a single dose of Cervarix, a great advantage to public health implementation programs Kreimer et al. ("Proof-of-principle evaluation of the efficacy of fewer than three doses of a bivalent HPV16/18 vaccine, The Journal of the National Cancer Institute, vol. 103, no. 19, pp. 1444-1451, 2011). In countries with screening programs, adenocarcinoma is the most difficult to detect and treat with later-stage presentation and higher mortality Smith et al. ("The rising incidence of adenocarcinoma relative to squamous cell carcinoma of the uterine cervix in the United States-a 24-year population-based study," Gynecologic Oncology, vol. 78, no. 2, pp. 97-105, 2000) and Gunnell et al. ("A longitudinal Swedish study on screening for squamous cell carcinoma and adenocarcinoma: evidence of effectiveness and overtreatment," Cancer Epidemiology Biomarkers and Prevention, vol. 16, no. 12, pp. 2641-2648, 2007). With additional cross-protection to HPV 31, 33, and 45 and protection against HPV 16 and 18 lasting at least 9.4 years, Cervarix may reduce adenocarcinomas in screened populations by more than 90%. This paper will detail the evidence about the efficacy, immunogenicity, and safety of Cervarix in the studied populations contrasting public health goals with individual health options.

Human papillomavirus genotypes in cervical intraepithelial neoplasia grade 3

BACKGROUND

There are few large case series describing the human papillomavirus (HPV) genotypes found in women diagnosed with rigorously reviewed cervical intraepithelial neoplasia grade 3 (CIN3), cervical precancer.

METHODS

The Atypical Squamous Cells of Undetermined Significance (ASCUS) and Low-Grade Squamous Intraepithelial Lesion (LSIL) Triage Study (ALTS) was a clinical trial to evaluate the best management strategies for women with equivocal (ASCUS) or mildly abnormal (LSIL) Pap tests. During enrollment and the 2-year follow-up, 608 women had a histopathologic diagnosis of CIN3 and PCR-based HPV genotyping results on cervical specimens. The genotyping results were ranked hierarchically according to cancer risk: HPV16 > other carcinogenic HPV > noncarcinogenic HPV > PCR negative.

RESULTS

Among the 608 women diagnosed with CIN3, 601 (98.8%) cases were positive for any HPV genotype and 95.4% for any carcinogenic HPV. HPV16 (59.9%), HPV31 (18.1%), HPV52 (14.8%), HPV51 (14.0%), and HPV18 (13.2%) were the five most common HPV genotypes detected. Younger age, consensus histologic confirmation, smoking, and multiparity increased the likelihood of testing HPV 16 positive. Specifically, HPV16-positive CIN3 occurred at a younger age than CIN3 positive for other carcinogenic HPV genotypes (median of 23.5 years versus 25 years, respectively; P = 0.0003, Kruskal-Wallis).

CONCLUSIONS

HPV16-positive CIN3 was more commonly diagnosed in younger women (versus older women), with consensus diagnosis (versus some disagreement between reviewers), and in smokers (versus nonsmokers), and was less commonly diagnosed in multiparous women compared CIN3 positive for other carcinogenic HPV genotypes.

IMPACT

In populations vaccinated against HPV16 (and HPV18), the median age of CIN3 in women with ASCUS and LSIL cytology should shift to older ages, possibly permitting later age at first screening.

Effectiveness of VIA, Pap, and HPV DNA testing in a cervical cancer screening program in a peri-urban community in Andhra Pradesh, India

Background

While many studies have compared the efficacy of Pap cytology, visual inspection with acetic acid (VIA) and human papillomavirus (HPV) DNA assays for the detection cervical intraepithelial neoplasia and cancer, few have evaluated the program effectiveness.

Methods and Findings

A population-based sample of 5603 women from Medchal Mandal in Andhra Pradesh, India were invited to participate in a study comparing Pap cytology, VIA, and HPV DNA screening for the detection of CIN3+. Participation in primary screening and all subsequent follow-up visits was rigorously tracked. A 20% random sample of all women screened, in addition to all women with a positive screening test result underwent colposcopy with directed biopsy for final diagnosis. Sensitivity, specificity, positive and negative predictive values were adjusted for verification bias. HPV testing had a higher sensitivity (100%) and specificity (90.6%) compared to Pap cytology (sensitivity  =  78.2%; specificity = 86.0%) and VIA (sensitivity = 31.6%; specificity = 87.5%). Since 58% of the sample refused involvement and another 28% refused colposcopy or biopsy, we estimated that potentially 87.6% of the total underlying cases of CIN3 and cancer may have been missed due to program failures.

Conclusions

We conclude that despite our use of available resources, infrastructure, and guidelines for cervical cancer screening implementation in resource limited areas, community participation and non-compliance remain the major obstacles to successful reduction in cervical cancer mortality in this Indian population. HPV DNA testing was both more sensitive and specific than Pap cytology and VIA. The use of a less invasive and more user-friendly primary screening strategy (such as self-collected swabs for HPV DNA testing) may be required to achieve the coverage necessary for effective reduction in cervical cancer mortality.

Using biomarkers as objective standards in the diagnosis of cervical biopsies

Histopathologic diagnosis of cervical biopsies determines clinical management of patients with an abnormal cervical cancer-screening test yet is prone to poor interobserver reproducibility. Immunohistochemical staining for biomarkers related to the different stages of cervical carcinogenesis may provide objective standards to reduce diagnostic variability of cervical biopsy evaluations but systematic, rigorous evaluations of their potential clinical utility are lacking. To address diagnostic utility of human papillomavirus (HPV) L1, p16(INK4a), and Ki-67 immunohistochemical staining for improving diagnostic accuracy, we conducted a community-based and population-based evaluation using 1455 consecutive cervical biopsies submitted to the Department of Pathology at the University of Virginia during a period of 14 months. Thin-sections of each biopsy from 1451 of 1455 (99.7%) biopsies underwent evaluation of immunohistochemical stains for the 3 biomarkers, masked to the original diagnosis, and the results were compared with an adjudicated, consensus diagnosis by 3 pathologists. p16 immunostaining, using the strongest staining as the cutpoint, was 86.7% sensitive and 82.8% specific for cervical intraepithelial neoplasia (CIN) grade 2 or more severe (CIN2(+)) diagnoses. The performance of p16(INK4a) was more sensitive (P<0.001), less specific (P<0.001), and of similar overall accuracy for CIN2(+) compared with the combined performance of all pathologist reviews in routine clinical diagnostic service (sensitivity=68.9%, specificity=97.2%). Ki-67 immunostaining was also strongly associated with a CIN2(+) diagnosis but its performance at all staining intensities was inferior to p16 immunostaining, and did not increase the accuracy of CIN2(+) diagnosis when combined with p16(INK4a) immunostaining compared with p16(INK4a) immunostaining alone. We found no utility for L1 immunostaining in distinguishing between CIN and non-CIN. In conclusion, with a rigorous evaluation, we found immunohistochemical staining for p16 to be a useful and reliable diagnostic adjunct for distinguishing biopsies with and without CIN2(+).

Invited commentary: Human papillomavirus infection and risk of cervical precancer--using the right methods to answer the right questions

Epidemiologists are well aware of the negative consequences of measurement error in exposure and outcome variables to their ability to detect putative causal associations. However, empirical proof that remedying the misclassification problem improves estimates of epidemiologic effect is seldom examined in detail. Of all areas in cancer epidemiology, perhaps the best example of the consequences of misclassification and of the steps taken to circumvent them was the pursuit, beginning in the mid-1980s, of the human papillomavirus (HPV) infection-cervical cancer association. The stakes were high: Had the wrong conclusions been reached epidemiologists would have been led astray in the search for competing hypotheses for the sexually transmissible agent causing cervical cancer or in ascribing to HPV infection a mere ancillary role among many lifestyle, hormonal, and environmental factors. The article by Castle et al. in this issue of the Journal (Am J Epidemiol. 2010;171(2):155-163) provides a detailed account of the joint influences of improved HPV and cervical precancer measurements in gradually unveiling the strong magnitude of the underlying association between viral exposure and cervical lesion risk. In this commentary, the authors extend the findings of Castle et al. by providing additional empirical evidence in support of their arguments.