p16(INK4a) immunohistochemistry is a promising biomarker to predict the outcome of low grade cervical intraepithelial neoplasia: comparison study with HPV genotyping

Possible role of negative human papillomavirus E6/E7 mRNA as a predictor of regression of cervical intraepithelial neoplasia 2 lesions in hr-HPV positive women

Background

The aim of this study was to evaluate the regression rate of CIN2 p16 positive lesions in women over 25 years of age and identify possible predictors of regression.

Methods

A total of 128 CIN2 p16 positive patients over 25 years old were considered. The women met the following inclusion criteria: HPV genotype 16, 18, 31, 33, 45 positive, HPV E6 / E7 mRNA test positive, without immune system pathologies, not pregnant and had completed at least two years of follow-up. At each follow-up examination patients were examined by colposcopy, HPV test, E6/E7mRNA, targeted biopsy and p16 protein detection. The final state after the two years of follow-up was classified as progression if the histology showed a CIN3, persistence if the lesion was a CIN2, regression if negative or LSIL. The predicted regression factors evaluated were: HPV E6/E7mRNA, protein p16.

Results

Overall, we had 35.1% (45 cases) of progression to CIN3, 41.4% (53 cases) of persistence and 23.4% (30 cases) of regression. The regression rate was higher in women with negative mRNA 92.8% (26/28), OR 312 (34.12–1798.76) p = 0.0001, while women with p16 negative had a regression of 22.6% (7/31), OR 0.94 (95% CI 0.36–2.46), p was not significant. We found no significant difference in regression between p16 positive (23.7%) and p16 negative (22.6%) CIN2 p16 lesions. p16 had a VPN of 22.6 (CI 95% 0.159–0.310), indicating that a p16 negative lesion does not exclude a CIN2 + .

Conclusions

We had a regression rate of 23.4%, which was low if we consider that in the literature the regression rates vary from 55 to 63%. The discrepancy in the results may indeed be explained by the fact that all lesions in our study were hr-HPV positive and belonged to “older women” reflecting a more "high-risk" population. As regression factors we studied p16 and HPV E6/E7 mRNA. The results of our study show that HPV mRNA, if negative, appears to be able to identify CIN2 lesions with a higher probability of regression and underlines how a p16 negative is not an indicator of regression.

Combining HPV DNA load with p16/Ki-67 staining to detect cervical precancerous lesions and predict the progression of CIN1-2 lesions

Background

Human Papilloma Virus (HPV) DNA tests are highly sensitive and can triage women with mild lesions, improving the prognosis and diagnosis of cervical lesions. However, additional efficient strategies should be developed to improve the specificity of these tests.

Methods

This study aimed to evaluate the clinical value of HPV DNA load in improving the diagnosis and prognosis of cervical lesions by p16/Ki-67 testing. Histological samples were collected from 350 women with HR-HPV genotyping and analyzed by qRT-PCR. Immunohistochemical staining was used to assess p16 and Ki-67 expression and clinical performance characteristics were calculated.

Results

Of the cases, 271 had detectable HR-HPV infection, in which HPV-16 was most prevalent (52.0%), followed by HPV-58 (22.5%). P16/Ki-67-positivity increased with histological severity but not for HR-HPV infection. Amongst the 13 HR-HPV genotypes, only HPV-16 (P = 0.016) and HPV-58 (P = 0.004) viral loads significantly correlated with lesion severity. The P16/Ki-67/HPV DNA load co-test indicated an increased sensitivity for the detection of cervical intraepithelial neoplasia (CIN) lesions compared to p16/Ki-67 staining in HPV-16 and/or 58 positive cases. Viral load did not improve the sensitivity of p16/Ki-67 co-test in non-HPV-16 or 58 positive cases. The clinical performance of the p16/Ki-67/HPV DNA load co-test was limited for the prediction of the outcome of CIN1 lesions. However, amongst the 12 HPV-16 and/or 58 positive CIN2 cases in which return visit results were obtained, the behavior of the lesions could be predicted, with a sensitivity, specificity, positive prediction rate (PPV), and negative prediction rate (NPV) of 0.667, 1, 1 and 0.5, respectively.

Conclusion

Combination of the assessment of HPV DNA load with the intensity of p16 and Ki-67 staining could increase the sensitivity of CIN lesion diagnosis and predict the outcome of CIN2 in patients with a HPV-16 and/or 58 infection.

Role of FAM19A4/miR124-2 methylation analysis in predicting regression or non-regression of CIN2/3 lesions: a protocol of an observational longitudinal cohort study

INTRODUCTION

The clinical course of high-grade cervical intraepithelial neoplasia (CIN2/3) is characterised by a high spontaneous regression rate. Histological assessment is unable to differentiate between CIN2/3 lesions likely to regress and those likely to persist or progress. Most CIN2/3 lesions are treated by surgical excision, leading to overtreatment of a substantial proportion. In this prospective study, we evaluate the value of DNA methylation of host cell genes, which has shown to be particularly sensitive for the detection of advanced CIN2/3 and cervical cancer, in the prediction of regression or non-regression of CIN2/3 lesions.

METHODS AND ANALYSIS

This is a multicentre observational longitudinal study with 24-month follow-up. Women referred for colposcopy with an abnormal cervical scrape, who have been diagnosed with CIN2/3 and a small cervical lesion (≤50% of cervix) will be asked to participate. Participants will be monitored by 6-monthly cytological and colposcopic examination. In case of clinical progression, participants will receive treatment and exit the study protocol. At baseline and during follow-up, self-sampled cervicovaginal brushes and cervical scrapes will be collected for high-risk human papillomavirus (HPV) testing and FAM19A4/miR124-2 methylation analysis. A colposcopy-directed biopsy will be taken from all participants at the last follow-up visit. The primary study endpoint is regression or non-regression at the end of the study based on the histological diagnosis. Regression is defined as CIN1 or less. Non-regression is defined as CIN2 or worse. The secondary study endpoint is defined as HPV clearance (double-negative HPV test at two consecutive time-points). The association between methylation status and regression probability will be evaluated by means of χ² testing.

ETHICS AND DISSEMINATION

Ethics approval was obtained in all participating clinics. Results of the main study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NTR6069; Pre-results.

p16INK4a and Ki-67 measurement predict progression of cervical low-grade squamous intraepithelial lesion

OBJECTIVE

To describe the natural history of low-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia grade I (LSIL/CIN1), and to analyze the predictive values of p16INK4a and Ki-67 for LSIL/CIN1 progression.

METHODS

From January 2013 to January 2016, 264 patients were diagnosed with CIN1 by colposcopy-assisted biopsy and were followed up at 1-year intervals at Peking University People's Hospital. We measured expression levels of biomarkers p16INK4a and Ki67 to predict progression, persistence, or regression of the disease. We used chi-square tests and logistic regression analysis to explore the relationships among LSIL/CIN1 progression, p16INK4a/Ki-67 expression, and patient age.

RESULTS

Among 264 patients with LSIL/CIN1, p16INK4a, Ki-67 expression and patient age > 30 years old were significantly associated with progression. Univariate analysis showed that age was not a risk factor for progression (P > 0.05) but that p16INK4a and Ki-67 expression were significantly associated with the progression (P < 0.05). Multivariate analysis showed that p16INK4a-positivity and high expression of Ki-67 protein were associated with LSIL/CIN1 progression, with odds ratios (OR) and 95% confidence intervals (CI) of 10.95 (3.04-39.53), and 9.7 (2.77-34.03), respectively.

CONCLUSION

p16INK4a-positivity and high expression of Ki-67correlated with LSIL/CIN1 progression. These markers may be independent predictors of LSIL/CIN1 progression.

Clinical and Economic Value of p16INK4a for the Differential Diagnosis of Morphologic Cervical Intraepithelial Neoplasia 2

The detection of high-grade intraepithelial lesions requires highly sensitive and specific methods that allow more accurate diagnoses. This contributes to a proper management of preneoplastic lesions, thus avoiding overtreatment. The purpose of this study was to analyze the value of immunostaining for p16 in the morphologic assessment of cervical intraepithelial neoplasia 2 lesions, to help differentiate between low-grade (p16-negative) and high-grade (p16-positive) squamous intraepithelial lesions. The direct medical cost of the treatment of cervical intraepithelial neoplasia 2 morphologic lesions was estimated. A retrospective observational cross-sectional study was carried out. This study analyzed 46 patients treated with excisional procedures because of cervical intraepithelial neoplasia 2 lesions, using loop electrosurgical excision procedures. Immunostaining for the biomarker was performed. For the estimation of overtreatment, percentages (%) and their 95% confidence interval were calculated. Of the 41 patients analyzed, 32 (78%) showed overexpression of p16 and 9 (22%) were negative (95% confidence interval, 11%-38%). Mean follow-up was 2.9 years, using cervical cytology testing (Pap) and colposcopy. High-risk human papillomavirus DNA tests were performed in 83% of patients. These retrospective results reveal the need for larger biopsy samples, which would allow a more accurate prediction of lesion risk. Considering the cost of p16 staining, and assuming the proper management of the low-grade lesion, an average of US$919 could be saved for each patient with a p16-negative result, which represents a global direct cost reduction of 10%.

Usefulness of p16INK4a staining for managing histological high-grade squamous intraepithelial cervical lesions

p16^INK4a (p16) tumor-suppressor protein is a biomarker of human papillomavirus (HPV) oncogenic activity that has revealed a high rate of positivity in histological high-gade squamous intraepithelial lesion/cervical intraepithelial neoplasia grade 2 (HSIL/CIN2) lesions. However, there is a paucity of data regarding p16 status as a surrogate marker of HSIL/CIN2 evolution. The aim of this study was to evaluate the outcome of HSIL/CIN2 patients followed up without treatment for 12 months according to p16 immunohistochemical staining. Patients diagnosed with HSIL/CIN2 colposcopy-directed biopsy, were recruited prospectively between December 2011 and October 2013. p16 staining was performed in all HSIL/CIN2 diagnostic biopsies. Follow-up was conducted every 4 months by cytology, colposcopy and biopsy if suspicion of progression and once the 12 months of follow-up completed. Complete regression, partial regression, persistence, and progression rates of HSIL/CIN2 were defined as a final outcome. A total of 96 patients were included in the analysis. The rate of spontaneous regression was 64%, while 28% had persistent disease, and 8% progressed at 12 months of follow-up. p16 was positive in 81 (84%) initial HSIL/CIN2 biopsies. Regression was observed in all 15 p16 negative cases and in 46 of 81 (57%) p16 positive cases (P=0.001). In conclusion, patients with p16 negative HSIL/CIN2 biopsy had a high rate of regression during first 12 months of follow-up. Status of p16 staining could be considered for HSIL/CIN2 management.

p16ink4 and cytokeratin 7 immunostaining in predicting HSIL outcome for low-grade squamous intraepithelial lesions: a case series, literature review and commentary

p16ink4 and cytokeratin 7 (CK7) have been proposed to identify low-grade squamous intraepithelial lesions (LSIL) at greater or lesser risk for an outcome of high-grade squamous intraepithelial lesion (HSIL). We correlated CK7 and p16ink4 staining in LSILs with outcome on follow-up and placed this information in the context of prior reports. Cervical LSIL biopsies with at least 1-year follow-up information were immunostained for CK7 and p16ink4. Follow-up outcomes included no SIL, LSIL (persistence) or HSIL (CIN2+). In all, 109 LSILs were studied and 18.3% stained positive for CK7. Ninety-one percent of CK7-negative LSILs regressed, 4.5% persisted, and 4.5% had an HSIL outcome, versus 60, 20, and 20% of CK7-positive LSILs, respectively (P=0.036). p16ink4 status did not significantly associate with outcome. Review of the literature revealed a highly variable rate of both positive p16ink4 immunoreactivity in LSIL and CIN2+ outcome for p16-positive LSIL but a consistently high negative predictive value (>90%) in the case of no/low p16 expression. Inter-observer reproducibility for the diagnosis of CIN2 in the literature ranged from poor to good, with unanimous agreement on the diagnosis of CIN2 occurring in less than 25% of cases. As with high-risk human papillomavirus testing, the most clinically useful result of p16ink4 staining is a negative test, implying no lesion or CIN1 and conferring a low risk of HSIL outcome. HSIL outcomes ('progression') are highly variable and are subject to wide differences in inter-observer interpretation for CIN2. This argues against the wisdom of relying on p16ink4 to both predict CIN2+ or upgrade CIN1 to CIN2. It also begs the question of whether CIN2 should be replaced by an alternate and less pejorative term (SIL of intermediate grade) for lesions that are not reproducibly classified as LSIL or HSIL, with an appropriate management scheme.

The association between p16 and Ki-67 immunohistostaining and the progression of cervical intraepithelial neoplasia grade 2

OBJECTIVE

To compare the frequency of p16- and Ki-67-positive cells on immunohistostaining among women with progression, persistence, or regression of cervical intraepithelial neoplasia grade 2 (CIN2).

METHODS

A retrospective study was conducted of women with CIN2 diagnosed by histology who were treated at a university hospital in Japan during 2004-2011. The immunostaining patterns for p16 and Ki-67 were analyzed and compared between patients with disease progression, persistence, or regression. Kaplan-Meier analysis was used to evaluate the progression rates stratified by immunostaining, and multivariate analysis of risk factors for progression was performed using the Cox proportional hazards model.

RESULTS

The analysis included 59 women with progression, 35 women with persistence, and 28 women with regression. Deep p16 expression (staining in more than half of the cervical intraepithelial compartment) and positive Ki-67 staining in more than 50% of cells were significantly more common among women with progression than among those with regression. The risk factors for progression of CIN2 were deep p16 expression (P<0.001) and a Ki-67 ratio of more than 50% (P<0.001).

CONCLUSION

Among women with CIN2, positive immunohistostaining for p16 and Ki-67 was strongly associated with disease progression.

Role of the Biomarker p16 in Downgrading -IN 2 Diagnoses and Predicting Higher-grade Lesions

In 2012, the College of American Pathologists and American Society for Colposcopy and Cervical Pathology published the "LAST" recommendations for histopathology reporting of human papilloma virus-related squamous lesions of the lower anogenital tract, including the use of a 2-tier nomenclature (low-grade squamous intraepithelial lesion/high-grade squamous intraepithelial lesion [LSIL/HSIL]) and expanded use of the biomarker p16 to classify equivocal lesions as either precancer (HSIL) or low-grade lesions (LSIL)/non-human papilloma virus changes. We aimed to determine (1) the frequency with which the poorly reproducible diagnosis of intermediate-grade (-IN 2) lesion in the lower anogenital tract would be downgraded on the basis of p16 results, and (2) whether p16 status was predictive of subsequent higher-grade lesions. A total of 200 specimens diagnosed as an intermediate-grade (-IN 2) lesion of the cervix (168), vagina (2), vulva (2), and anus (28) were reviewed and immunostained for p16. Slides were independently reviewed by 2 pathologists, with discrepant p16 interpretations adjudicated by a third pathologist. Of the 200 cases, 32% were negative for p16. Among the 166 patients with subsequent pathology (including 131 excisions), 26.2% of p16-positive cases versus 4.4% of p16-negative cases were associated with a subsequent diagnosis of HSIL (-IN 3) or worse (P=0.002). Reproducibility of the biopsy diagnosis was fair, with no significant difference with the addition of p16 or using 2 versus 3 tiers. In 11.5% of cases, there was discordance in p16 interpretation (κ 0.735, good agreement). The results indicate that using the Lower Anogenital Squamous Terminology recommendations would result in approximately one third of equivocal (-IN 2) diagnoses being downgraded to LSIL over 1 year in a busy academic practice. The significant association of p16 expression with a higher risk for HSIL on a subsequent specimen suggests that use of p16 to adjudicate equivocal (-IN 2) diagnoses in lower anogenital tract specimens as either LSIL or HSIL would likely predict lesion grade more accurately and avoid unnecessary excisional procedures.

Investigating Diagnostic Problems of CIN1 and CIN2 Associated With High-risk HPV by Combining the Novel Molecular Biomarker PanHPVE4 With P16INK4a

Grading cervical intraepithelial neoplasia (CIN) determines clinical management of women after abnormal cytology with potential for overdiagnosis and overtreatment. We studied a novel biomarker of human papillomavirus (HPV) life-cycle completion (panHPVE4), in combination with the minichromosome maintenance (MCM) protein cell-cycle marker and the p16INK4a transformation marker, to improve CIN diagnosis and categorization. Scoring these biomarkers alongside CIN grading by 3 pathologists was performed on 114 cervical specimens with high-risk (HR) HPV. Interobserver agreement for histopathology was moderate (κ=0.43 for CIN1/negative, 0.54 for CIN2/≤CIN1, and 0.36 for CIN3). Agreement was good or excellent for biomarker scoring (E4: κ=0.896; 95% confidence interval [CI]: 0.763-0.969; p16INK4a : κ=0.798; 95% CI: 0.712-0.884; MCM: κ=0.894; 95% CI: NC (this quantity cannot be calculated). Biomarker expression was studied by immunofluorescence and immunohistochemistry and was correlated with 104 final CIN diagnoses after histologic review. All 25 histologically negative specimens were p16INK4a and panHPVE4 negative, although 9 were MCM-positive. There were variable extents of p16INK4a positivity in 11/11 CIN1 and extensive panHPVE4 staining in 9/11. Ten CIN2 lesions expressed panHPVE4 and p16INK4a, and 13 CIN2 expressed only p16INK4a. CIN3 showed extensive p16INK4a positivity with no/minimal panHPVE4 staining. PanHPVE4, unlike MCM, distinguished CIN1 from negative. PanHPVE4 with p16INK4a separated CIN2/3 showing only expression of p16INK4a, indicating transforming HR-HPV E7 expression, from CIN1/2 showing completion of HR-HPV life cycle by E4 expression and variable p16INK4a expression. PanHPVE4 and p16INK4a staining are complementary markers that could provide simple, reliable support for diagnosing CIN. Their value in distinguishing CIN1/2 that supports HR-HPV life-cycle completion (and which might ultimately regress) from purely transforming CIN2/3 needing treatment warrants further research.

Correlation of P16 (Ink4a) and CK17 to HPV (16E6+18E6) in Premalignant and Malignant Lesions of Uterine Cervix: A Clinicopathologic Study

BACKGROUND

This research was accomplished to evaluate the IHC expression of p16 (ink4a) and CK17 in low grade cervical intraepithelial lesions (LSIL), high grade cervical intraepithelial lesions (HSIL) and invasive cervical carcinomas and to assess their correlation to HPV (16E6+18E6).

METHODS

The study included (127) formalin-fixed paraffin-embedded cervical biopsies; of which 22 cases were chronic cervicitis, 24 cases were LSIL, 28 cases were HSIL and 53 cases were invasive cervical carcinomas. Sections were immunohistochemically stained for p16 (ink4a), CK17 and HPV (16E6+18E6).

RESULTS

The study established a highly significant increase in IHC of expression of p16 (ink4a), CK17 and HPV (16E6+18E6) from LSIL through HSIL to invasive carcinomas (P-value˂0.001). There was non-significant association between IHC expression of all makers with age of patients; types, grade and stage of cervical carcinomas (P-value˃0.05). HPV (16E6+18E6) revealed a significantly positive correlation with p16 (ink4a) (P-value˂0.05) and a non- significant correlation with CK17 (P-value˃0.05); in LSIL, HSIL and invasive carcinoma cases.

CONCLUSION

p16 (ink4a) expression directly reflects infection with high risk HPV in cervical lesions and can add a significant diagnostic accuracy in the evaluation of CIN. CK 17 is a good marker of malignant transformation, with increasing in its expression according to the severity of cervical lesions; however, it is not related to HPV infection. Both markers are not related to prognostic variables of patients with cervical carcinoma.

[Primary cervical cancer screening]

Cervico-uterine cancer screening with cytology decrease incidence by more than 50%. The cause of this cancer is the human papilloma virus high risk, and requires a sensitive test to provide sufficient sensitivity and specificity for early detection and greater interval period when the results are negative. The test of the human papilloma virus high risk, is effective and safe because of its excellent sensitivity, negative predictive value and optimal reproducibility, especially when combined with liquid-based cytology or biomarkers with viral load, with higher sensitivity and specificity, by reducing false positives for the detection of cervical intraepithelial neoplasia grade 2 or greater injury, with excellent clinical benefits to cervical cancer screening and related infection of human papilloma virus diseases, is currently the best test for early detection infection of human papillomavirus and the risk of carcinogenesis.

Quantifying mRNA and microRNA with qPCR in cervical carcinogenesis: a validation of reference genes to ensure accurate data

A number of recent studies have catalogued global gene expression patterns in a panel of normal, tumoral cervical tissues so that potential biomarkers can be identified. The qPCR has been one of the most widely used technologies for detecting these potential biomarkers. However, few studies have investigated a correct strategy for the normalization of data in qPCR assays for cervical tissues. The aim of this study was to validate reference genes in cervical tissues to ensure accurate quantification of mRNA and miRNA levels in cervical carcinogenesis. For this purpose, some issues for obtaining reliable qPCR data were evaluated such as the following: geNorm analysis with a set of samples which meet all of the cervical tissue conditions (Normal + CIN1 + CIN2 + CIN3 + Cancer); the use of individual Ct values versus pooled Ct values; and the use of a single (or multiple) reference genes to quantify mRNA and miRNA expression levels. Two different data sets were put on the geNorm to assess the expression stability of the candidate reference genes: the first dataset comprised the quantities of the individual Ct values; and the second dataset comprised the quantities of the pooled Ct values. Moreover, in this study, all the candidate reference genes were analyzed as a single “normalizer”. The normalization strategies were assessed by measuring p16^INK4a and miR-203 transcripts in qPCR assays. We found that the use of pooled Ct values, can lead to a misinterpretation of the results, which suggests that the maintenance of inter-individual variability is a key factor in ensuring the reliability of the qPCR data. In addition, it should be stressed that a proper validation of the suitability of the reference genes is required for each experimental setting, since the indiscriminate use of a reference gene can also lead to discrepant results.

Molecular targets of HPV oncoproteins: potential biomarkers for cervical carcinogenesis

Cervical cancer is the second most common cancer among women worldwide and is responsible for 275,000 deaths each year. Persistent infection with high-risk human papillomavirus (HR-HPV) is an essential factor for the development of cervical cancer. Although the process is not fully understood, molecular mechanisms caused by HPV infection are necessary for its development and reveal a large number of potential biomarkers for diagnosis and prognosis. These molecules are host genes and/or proteins, and cellular microRNAs involved in cell cycle regulation that result from disturbed expression of HR-HPV E5, E6 and E7 oncoproteins. One of the current challenges in medicine is to discover potent biomarkers that can correctly diagnose cervical premalignant lesions and standardize clinical management. Currently, studies are showing that some of these molecules are potential biomarkers of cervical carcinogenesis, and it is possible to carry out a more accurate diagnosis and provide more appropriate follow-up treatment for women with cervical dysplasia. In this paper, we review recent research studies on cell cycle molecules deregulated by HPV infections, as well as their potential use for cervical cancer screening.

Clinicopathological implications of human papilloma virus (HPV) L1 capsid protein immunoreactivity in HPV16-positive cervical cytology

BACKGROUND

The objective of this study was to investigate the expression of human papilloma virus (HPV) L1 capsid protein in abnormal cervical cytology with HPV16 infection and analyze its association with cervical histopathology in Korean women.

MATERIAL AND METHODS

We performed immunocytochemistry for HPV L1 in 475 abnormal cervical cytology samples from patients with HPV16 infections using the Cytoactiv(®) HPV L1 screening set. We investigated the expression of HPV L1 in cervical cytology samples and compared it with the results of histopathological examination of surgical specimens.

RESULTS

Of a total of 475 cases, 188 (39.6%) were immunocytochemically positive and 287 (60.4%) negative for HPV L1. The immunocytochemical expression rates of HPV L1 in atypical squamous cells of unknown significance (ASCUS), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and cancer were 21.8%, 59.7%, 19.1%, and 0.0%, respectively. LSIL exhibited the highest rate of HPV L1 positivity. Of a total of 475 cases, the multiple-type HPV infection rate, including HPV16, in HPV L1-negative cytology samples was 27.5%, which was significantly higher than that in HPV L1-positive cytology samples (p = 0.037). The absence of HPV L1 expression in ASCUS and LSIL was significantly associated with high-grade (≥ cervical intraepithelial neoplasia [CIN] 2) than low-grade (≤ CIN1) histopathology diagnoses (p < 0.05), but was not significantly different between HPV16 single and multiple-type HPV infections (p > 0.05). On the other hand, among 188 HPV L1-positive cases, 30.6% of multiple-type HPV infections showed high-grade histopathology diagnoses (≥ CIN3), significantly higher than the percentage of HPV16 single infections (8.6%) (p = 0.0004) CONCLUSIONS: Our study demonstrates that the expression of HPV L1 is low in advanced dysplasia. Furthermore, the absence of HPV L1 in HPV16-positive low-grade cytology (i.e., ASCUS and LSIL) is strongly associated with high-grade histopathology diagnoses. The multiplicity of HPV infections may have an important role in high-grade histopathology diagnoses (≥ CIN3) in HPV L1-positive cases.

P16INK4A as a surrogate biomarker for human papillomavirus-associated oropharyngeal carcinoma: consideration of some aspects

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinomas (OPSCCs) frequently show different clinical and pathological features, which tend to be younger age, better performance status, less tobacco and alcohol consumption, more poorly differentiated histopathology, but usually with better treatment response and prognosis compared with HPV-negative OPSCCs. In tumor tissue, HPV infection is closely correlated with p16(INK4A) expression, which has been suggested to be a surrogate biomarker of HPV infection. However, there is diversity of sensitivity and specificity about p16(INK4A) in surrogate detection of HPV status. Herein, we summarize the current knowledge and note some aspects for consideration concerning p16(INK4A) as a surrogate biomarker for HPV-associated OPSCC.