p16INK4a immunostaining as an alternative to histology review for reliable grading of cervical intraepithelial lesions

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

INTRODUCTION

Immunostaining with p16^INK4a (p16), a tumor-suppressor surrogate protein biomarker for high-risk human papillomavirus (hrHPV) oncogenic activity, may complement standard hematoxylin and eosin (H&E) histology review, and provide more objective criteria to support the cervical intraepithelial neoplasia (CIN) diagnosis. With this study we assessed the impact of p16 immunohistochemistry on CIN grading in an hrHPV-based screening setting.

MATERIAL AND METHODS

In this post-hoc analysis, 326 histology follow-up samples from a group of hrHPV-positive women were stained with p16 immunohistochemistry. All H&E samples were centrally revised. The pathologists reported their level of confidence in classifying the CIN lesion.

RESULTS

Combining H&E and p16 staining resulted in a change of diagnosis in 27.3% (n = 89) of cases compared with the revised H&E samples, with a decrease of 34.5% (n = 18) in CIN1 and 22.7% (n = 15) in CIN2 classifications, and an increase of 18.3% (n = 19) in no CIN and 20.7% (n = 19) in CIN3 diagnoses. The level of confidence in CIN grading by the pathologist increased with adjunctive use of p16 immunohistochemistry to standard H&E.

CONCLUSIONS

This study shows that adjunctive use of p16 immunohistochemistry to H&E morphology reduces the number of CIN1 and CIN2 classifications with a proportional increase in no CIN and CIN3 diagnoses, compared with standard H&E-based CIN diagnosis alone. The pathologists felt more confident in classifying the material with H&E and p16 immunohistochemistry than by using H&E alone, particularly during assessment of small biopsies. Adjunctive use of p16 immunohistochemistry to standard H&E assessment of CIN would be valuable for the diagnostic accuracy, thereby optimizing CIN management and possibly decreasing overtreatment.

Cervical Cancers: Varieties and the Lower Anogenital Squamous Terminology

Carcinoma of cervix is classified as per the WHO classification into primary tumors which are predominantly epithelial tumors, mesenchymal tumors and tumor like lesions, mixed epithelial stromal tumors, melanocytic, germ cell, and lymphoid tumors. Secondary tumors are uncommon. Squamous cell carcinoma (SCC) in various morphological forms needs to be separated from other epithelial tumors for treatment modality selection. Majority of SCC are human papilloma virus (HPV) positive. The histological pattern, HPV type, and grading do not affect prognosis. Mixed mesenchymal and epithelial tumors are of Mullerian origin. Among sarcomas, Botryoid rhabdomyosarcoma needs to be looked for, as a small biopsy may miss it. Carcinoma cervix is not the only cancer caused by HPV. High-risk HPV is implicated in causation of various other cancers such as anal cancers, oropharyngeal cancers, vulval cancers, vaginal cancers, and penile cancers. Low-risk HPV viruses similarly cause infections of perianal and genital region in males and females. The terminology for these lesions has evolved before understanding of pathogenesis of low- and high-risk HPV. The lower anogenital squamous terminology (LAST), an acronym for LAST, incorporates the low- and high-grade squamous intraepithelial lesion (HSIL) terminology. In invasive cancers, a superficially invasive SCC is a well-defined entity. LAST outlines areas where p16 use is recommended. No benefit of addition of other biomarkers like p63 or ki67 is found in problem-solving in differentiation of HSIL from mimics or low-grade squamous intraepithelial lesion. Routine use of biomarkers is not advocated.

Utility of p16INK4a expression for the interpretation of uterine cervical biopsies in Kenya

Introduction

histologic interpretation of hematoxylin and eosin-stained cervical biopsies is subject to substantial discordance among pathologists. Immunohistochemical staining for p16INK4a can reduce inter-observer disagreement. We did a cross-sectional study to evaluate the utility of p16INK4a staining in the assessment of cervical biopsies in Nairobi, Kenya.

Methods

hematoxylin and eosin-stained sections from 91 colposcopic biopsies diagnosed as negative for dysplasia or as cervical intraepithelial neoplasia (CIN) grade 1-3 from 2011-2013 in Nairobi, Kenya, were reviewed and immunostained for p16INK4a. Agreement in interpretation of cervical biopsies was compared between primary and consensus review results.

Results

on primary evaluation, 16 cases were negative for squamous dysplasia; 23 were CIN 1; 37 CIN 2; and 15 CIN 3. On consensus review, 32 cases were negative for dysplasia; 19 were CIN 1; 16 CIN 2 and 24 CIN 3. Agreement was moderate between primary and consensus histology review results for the diagnosis of low-grade versus high-grade squamous intraepithelial lesions (Kappa = 0.568). None of the cases negative for dysplasia were positive for p16INK4a expression, but in primary and consensus review results, 17% and 5% cases of CIN 1; 49% and 69% of CIN 2, and 80% and 96% of CIN 3 were p16INK4a positive, respectively.

Conclusion

there was significant variability in the interpretation of cervical biopsies on hematoxylin and eosin between primary and consensus review assessments. 75% of CIN 1 cases that were upgraded to CIN 2 during consensus review expressed p16INK4a. These findings demonstrate the role of p16INK4a in increasing diagnostic accuracy and as a marker of high-grade CIN 2/3.

Association between PEG3 DNA methylation and high-grade cervical intraepithelial neoplasia

Background

Epigenetic mechanisms are hypothesized to contribute substantially to the progression of cervical intraepithelial neoplasia (CIN) to cervical cancer, although empirical data are limited.

Methods

Women (n = 419) were enrolled at colposcopic evaluation at Duke Medical Center in Durham, North Carolina. Human papillomavirus (HPV) was genotyped by HPV linear array and CIN grade was ascertained by biopsy pathologic review. DNA methylation was measured at differentially methylated regions (DMRs) regulating genomic imprinting of the IGF2/H19, IGF2AS, MESTIT1/MEST, MEG3, PLAGL1/HYMAI, KvDMR and PEG10, PEG3 imprinted domains, using Sequenom-EpiTYPER assays. Logistic regression models were used to evaluate the associations between HPV infection, DMR methylation and CIN risk overall and by race.

Results

Of the 419 participants, 20 had CIN3+, 52 had CIN2, and 347 had ≤ CIN1 (CIN1 and negative histology). The median participant age was 28.6 (IQR:11.6) and 40% were African American. Overall, we found no statistically significant association between altered methylation in selected DMRs and CIN2+ compared to ≤CIN1. Similarly, there was no significant association between DMR methylation and CIN3+ compared to ≤CIN2. Restricting the outcome to CIN2+ cases that were HR-HPV positive and p16 staining positive, we found a significant association with PEG3 DMR methylation (OR: 1.56 95% CI: 1.03–2.36).

Conclusions

While the small number of high-grade CIN cases limit inferences, our findings suggest an association between altered DNA methylation at regulatory regions of PEG3 and high grade CIN in high-risk HPV positive cases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13027-021-00382-3.

Grading immunohistochemical markers p16INK4a and HPV E4 identifies productive and transforming lesions caused by low- and high-risk HPV within high-grade anal squamous intraepithelial lesions

OBJECTIVES

Because current guidelines recognise high-grade anal squamous intraepithelial lesions (HSILs) and low-grade SILs (LSILs), and recommend treatment of all HSILs although not all progress to cancer, this study aims to distinguish transforming and productive HSILs by grading immunohistochemical (IHC) biomarkers p16INK 4a (p16) and E4 in low-risk human papillomavirus (lrHPV) and high-risk (hr)HPV-associated SILs as a potential basis for more selective treatment.

METHODS

Immunostaining for p16 and HPV E4 was performed and graded in 183 biopsies from 108 HIV-positive men who have sex with men. The causative HPV genotype of the worst lesion was identified using the HPV SPF10-PCR-DEIA-LiPA25 version 1 system, with laser capture microdissection for multiple infections. The worst lesions were scored for p16 (0-4) to identify activity of the hrHPV E7 gene, and panHPV E4 (0-2) to mark HPV production and life cycle completion.

RESULTS

There were 37 normal biopsies, 60 LSILs and 86 HSILs, with 85% of LSILs caused by lrHPV and 93% of HSILs by hrHPV. No normal biopsy showed E4, but 43% of LSILs and 37% of HSILs were E4 positive. No differences in E4 positivity rates were found between lrHPV and hrHPV lesions. Most of the lesions caused by lrHPV (90%) showed very extensive patchy p16 staining; p16 grade in HSILs was variable, with frequency of productive HPV infection dropping with increasing p16 grade.

CONCLUSIONS

Combined p16/E4 IHC identifies productive and nonproductive HSILs associated with hrHPV within the group of HSILs defined by the Lower Anogenital Squamous Terminology recommendations. This opens the possibility of investigating selective treatment of advanced transforming HSILs caused by hrHPV, and a 'wait and see' policy for productive HSILs. What's already known about this topic? For preventing anal cancer in high-risk populations, all patients with high-grade squamous intraepithelial lesions (HSILs) are treated, even though this group of lesions is heterogeneous, the histology is variable and regression is frequent. What does this study add? By adding human papillomavirus (HPV) E4 immunohistochemistry to p16 INK4a (p16), and grading expression of both markers, different biomarker expression patterns that reflect the heterogeneity of HSILs can be identified. Moreover, p16/E4 staining can separate high-risk HPV-associated HSILs into productive and more advanced transforming lesions, providing a potential basis for selective treatment.

Role of p16/INK4a and Ki-67 as specific biomarkers for cervical intraepithelial neoplasia: An institutional study

BACKGROUND:

P16/INK4a and Ki-67 have emerged as important biomarkers for the detection of high-risk human papilloma virus (HR-HPV) associated dysplastic changes in the cervical biopsy samples. The increasing inter- and intra-observer variability in the diagnosis of dysplastic lesions and immature squamous metaplasia on histopathology has led to the advent of these biomarkers. This study was taken up with an aim to study their role in increasing the diagnostic accuracy in equivocal cases on histopathology.

MATERIALS AND METHODS:

Fifty cervical biopsy specimens were stained with p16/INK4a and Ki-67 consisting of 10 cases each of cervical intraepithelial neoplasia (CIN I/II/III) along with five cases of squamous metaplasia. Histopathological diagnosis was considered as the gold standard. Statistical analysis was done by kappa statistics, and P value was calculated.

RESULTS:

The sensitivity and specificity of p16/INK4a and Ki-67 were 76.2%, 87.5%, 90.5%, and 87.5%, respectively. The overall agreement of both the immunostains with histopathological diagnosis was statistically significant (P < 0.05) and the diagnostic accuracy improved when both the stains were used in conjunction.

CONCLUSION:

Ki-67 and p16/INK4a can be used as complimentary tests in differentiating dysplastic and nondysplastic lesions and help in confirming the histopathological diagnosis. They aid in recognition of dysplasias caused by HR-HPV, which have higher tendency to progress to neoplasia. However, further research is advocated before the widespread use of these markers for screening of dysplasias.

Expression of p16 and HPV E4 on biopsy samples and methylation of FAM19A4 and miR124-2 on cervical cytology samples in the classification of cervical squamous intraepithelial lesions

The decision to treat a cervical squamous intraepithelial lesion (SIL) by loop electrosurgical excision procedure (LEEP) relies heavily on a colposcopy-directed biopsy showing high-grade (H)SIL. Diagnosis is often supported by p16, an immunohistochemical (IHC) biomarker of high-risk (hr)HPV E7 gene activity. Additional potential markers include methylation of tumor suppressor genes FAM19A4/miR124-2 in cervical cytology for advanced transforming HSIL and the IHC marker HPV E4 for productive, potentially regressing lesions. In 318 women referred for colposcopy, we investigated the relationship between staining patterns of p16 and E4 IHC in the worst biopsy, and the relation of these to FAM19A4/miR124-2 methylation status in cytology. E4-positive staining decreased with increasing SIL/CIN grade from 41% in LSIL to 3% in HSIL/CIN3. E4 positivity increased with grade of p16 when p16 expression was limited to the lower two third of the epithelium (r = 0.378), but fell with expression over. Loss of E4 expression in the worst lesion was associated with the methylation of FAM19A4/miR124-2. We also examined whether these biomarkers can predict the histological outcome of the LEEP biopsy in a subgroup of 119 who underwent LEEP treatment. About 85% of women with ≥lower two third p16 staining/E4-negative HSIL biopsies and 65% with limited p16 staining/E4-positive HSIL biopsies had ≥HSIL in the LEEP specimen (P = .025). p16 expression in a biopsy is related both to viral production and transformation, while decreased E4 expression relates to methylation, indicating advanced HSIL. p16 expression in ≥2/3 of the epithelium and absent E4 indicate likely HSIL on a subsequent LEEP specimen.

HPV-mediated down-regulation of NOD1 inhibits apoptosis in cervical cancer

Cervical cancer is the fourth most common malignant tumor in women worldwide. The persistent infection of high-risk Human Papillomavirus (hrHPV) is considered to be the primary cause of this disease. As an innate immune receptor, the nucleotide-binding oligomerization domain protein-1 (NOD1) recognizes the pathogen-associated molecular pattern (PAMP), subsequently initiating immune responses. NOD1 is also involved in the apoptotic signaling pathway and mutates in many cancer cells. In the study, we revealed that NOD1 expression decreased during the progression of cervical intraepithelial neoplasia to cervical cancer and that HPV16 E6/E7 oncoproteins induced down-regulation of NOD1. Moreover, the activation of NOD1 promoted the apoptosis of HPV16-positive cervical cancer cells. The data indicated that the dysregulation of NOD1-mediated inflammation and apoptosis may contribute to cervical intraepithelial neoplasia progression and cervical cancer.

Presence or Absence of Significant HPVE4 Expression in High-grade Anal Intraepithelial Neoplasia With p16/Ki-67 Positivity Indicates Distinct Patterns of Neoplasia: A Study Combining Immunohistochemistry and Laser Capture Microdissection PCR

Progression of anal intraepithelial neoplasia (AIN) involves transition from productive to transforming human papillomavirus (HPV) infection. Grading aims to distinguish productive low-grade AIN from high-grade anal intraepithelial neoplasia (HGAIN) with risk of cancer. We describe immunohistochemical patterns in AIN adding a novel marker for initiation of the productive phase of the HPV life cycle (panHPVE4) to those for cell cycle activity (Ki-67) and transforming activity of HPVE7 gene (p16). We studied 67 anal biopsies for suspected anal neoplasia (17 normal, 15 AIN1, 20 AIN2, 15 AIN3) from 54 men who have sex with men at New York Presbyterian Hospital, USA. Two pathologists generated consensus AIN and immunogrades. Whole tissue and laser capture microdissection samples from multiple HPV-infected biopsies were tested for HPV with SPF10-PCR-DEIA-LiPA25, version 1. (Para)basal Ki-67 expression distinguished normal from AIN (≥lower-third Ki-67) with sensitivity 0.92 and specificity 1.0. Ki-67 did not distinguish grades of AIN. Null/patchy p16 versus diffuse ≥lower-third patterns discriminated HGAIN (sensitivity, 1.0; specificity, 0.84). There was marked heterogeneity in E4 expression within HGAIN. Most AIN2 (14/20) was E4 versus 0/15 AIN3 (sensitivity, 0.70; specificity 1.0). HPV was detected in 63 (94%) biopsies, with 49 (77.8%) high-risk HPV. HPV16 was the most frequent (13%). Multiple HPV genotypes were found in 15 (24%) biopsies and laser capture microdissection -polymerase chain reaction confirmed specific HPV types in E4 +/- AIN. Although Ki-67 discriminated AIN and p16 HGAIN, E4/p16 staining shows that most AIN2 is different from transformed AIN3 in showing both entry into productive HPV infection and transforming activity.

p16 Immunohistochemistry Is Not Always Required For Accurate Diagnosis of Grade 2 Squamous Intraepithelial Lesions

OBJECTIVES

Preinvasive squamous neoplasms of the lower genital tract are currently classified using a two-tier system (high- or low-grade squamous intraepithelial lesion) as directed by the Lower Anogenital Squamous Terminology (LAST) guidelines but may also be subclassified as intraepithelial neoplasia grade 1 (-IN1), -IN2, or -IN3. The LAST recommended that all diagnoses of -IN2 be supported by immunohistochemistry (IHC) for p16. We examined whether p16 and Ki-67 IHC are necessary to diagnose -IN2 when the lesion has obvious high-grade histology.

MATERIALS AND METHODS

p16 and Ki-67 IHC were performed prospectively and retrospectively on vulvar, vaginal, and cervical specimens with an initial diagnosis of -IN2 based on hematoxylin and eosin morphology, and a final diagnosis was made after consensus review.

RESULTS

Five of 46 prospective and four of 38 retrospective cases were p16 negative. The diagnosis of -IN2 was maintained in eight of these nine cases because of compelling high-grade squamous intraepithelial lesion histology. Overall, p16 and Ki-67 IHC altered the -IN2 diagnosis to a lower grade in only one of 84 cases (1.2%, <0.01%-7.1%). Moreover, p16 was positive in all cases where the preanalytic impression was of -IN2/3 (13/13).

CONCLUSIONS

p16 IHC lacks utility in cases of morphologically obvious -IN2, because the stain is positive in most cases. The LAST recommendation to use p16 IHC to support all diagnoses of -IN2 will result in performing the immunostain in many circumstances where it is not medically necessary. Among cases that are p16 negative, many have compelling high-grade morphology. The LAST perspective that the stain trumps histology may allow false-negative IHC results to prevail.

Potential influence of p16 immunohistochemical staining on the diagnosis of squamous cell lesions in cervical biopsy specimens: observation from cytologic-histologic correlation

BACKGROUND

The p16 immunohistochemical (IHC) marker has been used increasingly as an adjunct to morphologic assessment of cervical biopsies in which the differential diagnoses include high-grade squamous intraepithelial lesion (HSIL) and its mimics. The objective of this study was to assess the potential influence of p16 IHC staining on the evaluation of cervical biopsy as observed through cytologic-histologic correlation (CHC).

METHODS

Cervical biopsy samples that had cytologic diagnoses of either low-grade squamous intraepithelial lesion (LSIL) or HSIL and also had histologic follow-up were retrieved from the department database. CHC and the use of p16 IHC from 2 periods (group 1, 2008; group 2, 2014-2016) were compared and analyzed.

RESULTS

Histology on 452 samples from patients who had prior LSIL cytology in group 1 yielded 126 benign (27.9%), 272 LSIL (60.2%), and 54 HSIL (11.9%) diagnoses. By comparison, 491 samples from the patients in group 2 yielded 106 benign (21.6%), 277 LSIL (56.4%), and 108 HSIL (22.0%) diagnoses. The difference in CHC discrepancies between the 2 groups was significant (P = .0001), mainly because of the increased diagnosis of HSIL in group 2. Although p16 IHC was not applied to any sample from group 1, it was performed on 141 of 491 samples (28.7%) from group 2. Further follow-up of patients who had histologic HSIL revealed that residual HSIL was identified significantly more often in those who did not have p16 IHC applied in the preceding cervical biopsy than in those did (P = .0004). A similar comparison was performed between 113 patients from group 1 and 152 patients from group 2 who had a prior diagnosis of HSIL cytology, and the difference was statistically insignificant.

CONCLUSIONS

The use of p16 IHC on cervical biopsies in patients who had a prior cytologic diagnosis of LSIL may lead to greater detection and upgrading of HSIL, thereby compounding the discrepancy in CHC.

Three-tiered score for Ki-67 and p16ink4a improves accuracy and reproducibility of grading CIN lesions

Aims

To investigate the accuracy and reproducibility of a scoring system for cervical intraepithelial neoplasia (CIN1–3) based on immunohistochemical (IHC) biomarkers Ki-67 and p16^ink4a.

Methods

115 cervical tissue specimens were reviewed by three expert gynaecopathologists and graded according to three strategies: (1) CIN grade based on H&E staining only; (2) immunoscore based on the cumulative score of Ki-67 and p16^ink4a only (0–6); and (3) CIN grade based on H&E supported by non-objectified IHC 2 weeks after scoring 1 and 2. The majority consensus diagnosis of the CIN grade based on H&E supported by IHC was used as the Reference Standard. The proportion of test positives (accuracy) and the absolute agreements across pathologists (reproducibility) of the three grading strategies within each Reference Standard category were calculated.

Results

We found that immunoscoring with positivity definition 6 yielded the highest proportion of test positives for Reference Standard CIN3 (95.5%), in combination with the lowest proportion of test positives in samples with CIN1 (1.8%). The proportion of test positives for CIN3 was significantly lower for sole H&E staining (81.8%) or combined H&E and IHC grading (84.8%) with positivity definition ≥CIN3. Immunoscore 6 also yielded high absolute agreements for CIN3 and CIN1, but the absolute agreement was low for CIN2.

Conclusions

The higher accuracy and reproducibility of the immunoscore opens the possibility of a more standardised and reproducible definition of CIN grade than conventional pathology practice, allowing a more accurate comparison of CIN-based management strategies and evaluation of new biomarkers to improve the understanding of progression of precancer from human papillomavirus infection to cancer.

Proposed Terminology for Anal Squamous Lesions: Its Application and Interobserver Agreement Among Pathologists in Academic and Community Hospitals

OBJECTIVES

To analyze interobserver reproducibility and compare practice patterns between academic and community settings of Lower Anogenital Squamous Terminology (LAST).

METHODS

In total, 132 anal biopsy slides were revised as well as p16 immunostains.

RESULTS

LAST was used in 49% of cases (academic center, 68%; satellite hospitals [community practice setting], 32%). After pathology review and consensus interpretation, 23 (17%) case diagnoses were reclassified: eight (34.8%) cases (benign or low-grade squamous intraepithelial lesion [LSIL]) were upgraded to high-grade squamous intraepithelial lesion (HSIL) (p16 confirmed ordered during review); four (17.4%) cases originally classified as HSIL were downgraded to LSIL (p16 originally ordered in one case). There was no significant difference in discrepancies between original and consensus diagnosis in the community vs academic setting or by subspecialty (gynecological vs gastrointestinal). Overall interobserver agreement among reviewers was substantial (κ = 0.63) and improved with the use of p16 immunostain in challenging cases (κ = 0.71; P < .001).

CONCLUSIONS

This new terminology is not yet uniformly used by pathologists in anal/perianal biopsy specimens; this two-tier system has a good interobserver agreement and is further improved with p16 use in appropriate cases.

Effect of Lower Anogenital Squamous Terminology Recommendations on the Use of p16 Immunohistochemistry and the Proportion of High-Grade Diagnoses in Cervical Biopsy Specimens

OBJECTIVES

The Lower Anogenital Squamous Terminology (LAST) group has recommended that cervical intraepithelial neoplasia (CIN) terminology be replaced by squamous intraepithelial lesion (SIL) terminology, with p16 immunohistochemistry used to separate lesions formerly diagnosed as CIN grade 2 into high-grade SILs (HSILs) and low-grade SILs. This study investigated the impact of these changes on the frequency of p16 testing and the diagnosis of high-grade lesions.

METHODS

Pathology reports for all cervical biopsy specimens in the 1 year before and after the introduction of LAST recommendations (July 2011 to June 2013) were examined.

RESULTS

Before and after the implementation of LAST, 365 (15.4%) of 2,376 cases were diagnosed as high grade (CIN 2/3) vs 486 (17.6%) of 2,761 cases diagnosed as HSILs (P = .0343), and p16 was performed 79 (3.3%) times vs 383 (13.9%) times (P < .0001).

CONCLUSIONS

Immunohistochemistry for p16 increased dramatically as a result of LAST recommendations, and high-grade diagnoses increased.

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.

p16 Immunohistochemistry is useful in confirming high-grade squamous intraepithelial lesions (HSIL) in women with negative HPV testing

SUMMARY

It is believed that almost all squamous cell carcinomas of the cervix are associated with HR-HPV infection. However, a subset of high-grade squamous intraepithelial lesion (HSIL) (CIN2 and CIN3) lesions is found in those women with negative HPV testing. Knowledge of HPV status can influence pathologists' decision in rendering the diagnosis of cervical squamous intraepithelial lesions (SIL). p16, a surrogate marker for HSIL, has been widely applied to facilitate accurate diagnosis of HPV-related cervical dysplasia, especially CIN2 and CIN3. To assess whether p16 immunostaining is useful in diagnosing HSIL in women with negative HPV testing, we studied the utility of p16 immunohistochemistry in 46 women of HSIL and HPV-negative status. A total of 46 cases of initial biopsies with histopathologically diagnosed HSIL (CIN2 and CIN3) were identified from our hospital archives. All women were HPV negative with at least 1 HPV testing using HC-II (Qiagen) within 6 mo of initial biopsy. LEEP procedures within 6 mo of initial biopsies were reviewed and documented. Immunohistochemical staining of p16 was performed on recuts of all original biopsies. Some LEEP specimens without evidence of HSIL (CIN2 and CIN3) on hematoxylin and eosin had recuts with deeper levels and p16 immunostaining to confirm the negative diagnosis. p16 immunostaining were evaluated as negative, focal/patchy, or diffuse staining pattern. Patients' HPV testing status and related clinicopathologic information were reviewed, tabulated, and correlated with p16 immunostaining patterns. Forty-six women between the age of 17 and 58 yr, with a median of 35 yr, were all HPV-negative. All women, except 2, had an abnormal cytologic interpretation at the time of HPV testing ranging from ASC-US to HSIL. Forty-two women (91.3%) had LEEP procedures done within 6 mo of the initial biopsies. LEEP specimens showed that 76.2% (32 cases) women had HSIL, including 22 cases of CIN2 and 10 cases of CIN3, 14.3% (6 cases) had low-grade squamous intraepithelial lesion (CIN1), and 9.5% (4 cases) had benign cervix. p16 immunostaining, performed on initial biopsies with histopathologic diagnoses of CIN2 or CIN3, showed that 66.7% (28 cases) had diffuse staining pattern, 16.7% (7 cases) had focal/patchy pattern, and 16.7% (7 cases) had negative p16 staining. On LEEP follow-up, all 28 cases with diffuse p16 staining pattern had HSIL (CIN2 and CIN3), and all 7 cases with negative p16 staining had no detectable high-grade dysplasia. For those 7 cases with focal/patch p16 staining pattern, 4 had HSIL (CIN2) and 3 had low-grade squamous intraepithelial lesion (CIN1) on LEEP follow-up. Approximately 76% of women with negative HPV and diagnosis of HSIL (CIN2 and CIN3) on initial biopsy had confirmed HSIL (CIN2 and CIN3) in subsequent LEEP follow-up. Diffuse p16 immunostaining pattern is the hallmark of HSIL because it correlates 100% with CIN2 and CIN3 lesions between initial biopsy and LEEP specimens, regardless of the HPV status. The negative predictive value for p16 immunoreactivity to predict cervical lesions less than high grade is almost 100% in our study. Our study suggests that when a woman is negative for HPV and also negative for p16, diagnosis of HSIL should be very cautious in void of unnecessary LEEP procedures.

The Interpretive Variability of Cervical Biopsies and Its Relationship to HPV Status

Diagnostic interpretation of a cervical biopsy is a key element in the decision to treat or not to treat a woman with an abnormal screening test. This study assesses the variability of these diagnostic interpretations on a population basis using the New Mexico HPV Pap Registry database. An experienced panel of gynecologic pathologists reviewed a stratified random sample of 6272 biopsies, which was then extrapolated to the entire population of 21,297 biopsies read by the community pathologists. Diagnoses by the community and panel pathologists were compared, and paired diagnoses were correlated with positivity for human papillomavirus 16 (HPV16) and any high-risk HPV as objective measures of progressive potential. Panel agreement with the community diagnosis was 38.2% for cervical intraepithelial neoplasia grade 1 (CIN1), 38.0% for CIN grade 2 (CIN2), 68.0% for CIN grade 3 (CIN3), and 70.6% for cancer. The κ value was 0.46 overall but higher for dichotomous categorization based on CIN2 or CIN3 cutoff points (0.68 and 0.67, respectively). On a population basis, there were fewer CIN1 and more negative diagnoses in the panel review but similar proportions of CIN2 and CIN3. HPV16 and high-risk HPV positivity increased with disease severity, but panel review did not improve the correlation of higher-grade disease with these objective measures. In this population-based study of the variability in cervical diagnoses, we noted significant variability in the community and panel diagnoses, especially for CIN2, the threshold for excisional treatment. New biomarkers are needed to more accurately stratify precursor lesions according to their malignant potential.

Clinical Implication of p16, Ki-67, and Proliferating Cell Nuclear Antigen Expression in Cervical Neoplasia: Improvement of Diagnostic Accuracy for High-grade Squamous Intraepithelial Lesion and Prediction of Resection Margin Involvement on Conization Specimen

Background:

Cervical intraepithelial neoplasia (CIN) grading is subjective and affected by substantial rates of discordance among pathologists. Although the use of p16INK4a (p16) staining has been proven to improve diagnostic accuracy for high-grade squamous intraepithelial lesion (HSIL), the clinical evidence for use of Ki-67 and proliferating cell nuclear antigen (PCNA) is insufficient to make an independent recommendation for use, alone or in combination. The primary objective was to evaluate clinical utility of Ki-67 and PCNA in combination with p16 in diagnosing HSIL. Also, we assessed the correlation between expressions of three biomarkers and resection margin status of conization specimen.

Methods:

The expressions of p16, Ki-67, and PCNA were evaluated by immunohistochemical methods in 149 cervical tissues encompassing 17 negative lesion, 31 CIN 1, 25 CIN 2, 41 CIN 3, and 35 invasive squamous cell carcinoma. The immunohistochemical staining results were classified into four grades: 0, 1+, 2+ and 3+.

Results:

The expression of three biomarkers was positively associated with CIN grade. Ki-67 immunostaining did not increase the accuracy of HSIL diagnosis when combined with p16 immunostaining compared with p16 immunostaining alone. In contrast, combining the staining results for p16 and PCNA (p16 = 3+ and PCNA ≥2+) increased its specificity (66.7% vs. 75.0%, P = 0.031) without decrease of its sensitivity (98.7% vs. 98.7%) for diagnosis of CIN 3 and more sever lesion. Subgroup analysis for conization specimen with CIN 2 and CIN 3 showed that positive Ki-67 immunostaining was an independent risk factor for predicting resection margin positivity (odds ratio = 6.52, 95% confidence interval 1.07–39.64).

Conclusions:

We found that the combined use of p16 and PCNA immunostaining enhanced diagnostic accuracy for HSIL. Positive Ki-67 immunostaining was associated with incomplete excision.

HPV-type distribution and reproducibility of histological diagnosis in cervical neoplasia in Poland

This study was performed to assess attribution of high grade cervical intraepithelial neoplasia (HG-CIN) and invasive cervical cancer (ICC) to human papillomavirus (HPV) genotypes and secondarily to assess reproducibility of HG-CIN/ICC diagnosis obtained in Poland. Formaldehyde fixed, paraffin embedded blocks of HG-CIN/ICC from two distant institutions were sent to a central laboratory together with original histological diagnoses. Central/expert review of histopathological specimens was performed and agreement between local and central/expert diagnoses was calculated. HPV detection and genotyping in the samples was carried out with the use of SPF10-LiPA25 technology. Results were analyzed for 205 HG-CIN and 193 ICC cases with centrally confirmed diagnoses. Kappa coefficients and 95 % confidence intervals for HG-CIN and ICC diagnoses were: 0.13 (0.09;0.17) and 0.19 (0.11;0.26) respectively. Cohen’s kappa coefficients for lesions with representative number of samples ranged from 0.01 for cervical intraepithelial neoplasia grade 2 to 0.75 for adenocarcinoma. HPV DNA was detected in 96.1 and 91.2 % of the confirmed HG-CIN and ICC specimens respectively. HPV positive HG-CIN was most commonly attributed to HPV types: 16 (62.8), 33 (7.8), 31 (6.6), 52 (3.7), 45 (2.6) and 58 (2.6 %). HPV positive ICC was most commonly attributed to HPV types: 16 (72.1), 18 (10.8), 33 (5.7), 45 (3.4) and 31 (1.7 %). Reproducibility of histological diagnosis of HG-CIN/ICC obtained in Poland generally increases with the severity of lesion and is lowest for cervical intraepithelial neoplasia grade 2 and highest for adenocarcinoma. Over 80 % of ICC cases are vaccine-preventable in Poland.

p16INK4a immunohistochemistry in cervical biopsy specimens: A systematic review and meta-analysis of the interobserver agreement

OBJECTIVES

The interpretation of cervical biopsy specimens guides management of women with suspected cervical cancer precursors. However, morphologic evaluation is subjective and has low interobserver agreement. Addition of p16(INK4a) immunohistochemistry may improve interpretation.

METHODS

We performed a systematic review and meta-analysis of published data on interobserver agreement of p16(INK4a) positivity using p16(INK4a) immunohistochemistry and of cervical intraepithelial neoplasia grade 2 (CIN2+) and CIN grade 3 (CIN3+) classification using H&E morphology in conjunction with p16(INK4a) in comparison with H&E morphology alone.

RESULTS

The literature search revealed five eligible articles. The results show strong agreement of pathologists' interpretation of cervical biopsy specimens as p16(INK4a) positive or negative (pooled κ = 0.90; 95% confidence interval [CI], 0.88-0.92) and significantly higher agreement for a CIN2+ diagnosis with H&E morphology in conjunction with p16(INK4a) (κ = 0.73; 95% CI, 0.67-0.79) compared with H&E morphology alone (κ = 0.41; 95% CI, 0.17-0.65). Also, a slightly higher agreement for CIN3+ can be observed (κ = 0.66; 95% CI, 0.39-0.94 for H&E morphology in conjunction with p16(INK4a) and κ = 0.61; 95% CI, 0.44-0.78 for H&E morphology alone), but this difference was not statistically significant.

CONCLUSIONS

The published literature indicates improved interobserver agreement of the diagnosis of CIN2+ with the conjunctive use of H&E morphology with p16(INK4a) immunohistochemistry compared with H&E morphology alone.

HPV-related squamous neoplasia of the lower anogenital tract: an update and review of recent guidelines

Squamous cell carcinomas of the lower anogenital tract that are related to human papillomavirus (HPV) infection represent a significant disease burden worldwide. The diagnosis and management of their noninvasive precursors has been the subject of extensive study and debate over several decades, accompanied by an evolving understanding of HPV biology. Recent new consensus recommendations for the pathologic diagnosis of these precursor lesions were published in 2012, the result of the Lower Anogenital Squamous Terminology project cosponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology. Most salient among the new guidelines are the recommendation to switch to a 2-tiered nomenclature (high-grade squamous intraepithelial lesion and low-grade squamous intraepithelial lesion) rather than the traditional 3-tiered "intraepithelial neoplasia" terminology, and the recommendation to expand use of the immunohistochemical marker p16 to distinguish between low-grade squamous intraepithelial lesion and high-grade squamous intraepithelial lesion/intraepithelial neoplasia 2. The goals of the project were to align diagnostic terminology with our knowledge of HPV biology, increase reproducibility, consolidate diverse systems of nomenclature, and ultimately better determine a patient's true cancer risk. The clinical guidelines for screening and management of cervical intraepithelial neoplasia have also been recently updated, most notably with a lengthening of screening intervals. In this review, we focus on the new guidelines put forth for pathologic diagnosis of HPV-related anogenital neoplasia, with discussion of the evidence behind them and their potential implications. We also provide an update on relevant biomarkers, clinical recommendations, and the newest developments relating to cervical neoplasia.

The clinical impact of using p16(INK4a) immunochemistry in cervical histopathology and cytology: an update of recent developments

Cervical cancer screening test performance has been hampered by either lack of sensitivity of Pap cytology or lack of specificity of Human Papillomavirus (HPV) testing. This uncertainty can lead to unnecessary referral and treatment, which is disturbing for patients and increases costs for health care providers. The identification of p16(INK4a) as a marker for neoplastic transformation of cervical squamous epithelial cells by HPVs allows the identification of HPV-transformed cells in histopathology or cytopathology specimens. Diagnostic studies have demonstrated that the use of p16(INK4a) immunohistochemistry substantially improves the reproducibility and diagnostic accuracy of histopathologic diagnoses. p16(INK4a) cytology has substantially higher sensitivity for detection of cervical precancer in comparison to conventional Pap tests. Compared to HPV DNA tests, immunochemical detection of p16(INK4a) -stained cells demonstrates a significantly improved specificity with remarkably good sensitivity. About 15 years after the initial observation that p16(INK4a) is overexpressed in HPV-transformed cells we review the accumulated clinical evidence suggesting that p16(INK4a) can serve as a useful biomarker in the routine diagnostic work up of patients with HPV infections and associated lesions of the female anogenital tract.

Usefulness of p16/Ki67 immunostaining in the triage of women referred to colposcopy

BACKGROUND

This study compared the performance of p16/Ki67 dual-staining and human papillomavirus (HPV) testing in women referred to colposcopy and sought to determine the usefulness of a morphological evaluation of the double-stained cells.

METHODS

This prospective study included 1123 women (mean age, 35.8 ± 10.9 years) referred to colposcopy from October 2009 to November 2012 due to positive HPV testing or abnormal cytology results (atypical squamous cells of unknown significance, or worse abnormalities). Liquid-based cytology specimens (PreservCyt, Hologic) were used for HPV detection (Hybrid Capture 2 [HC2]; Qiagen) and p16/Ki67 dual-staining (CINtec Plus; Roche-mtm Laboratories). All women underwent histological study. After completion of the study, 18 patients were classified as having cervical cancer (CC), 378 had a high-grade squamous intraepithelial lesion (HSIL), 304 had a low-grade squamous intraepithelial lesion, and 423 were negative.

RESULTS

The sensitivity and specificity of p16/Ki67 dual-staining for HSIL/CC were 90.9% (95% confidence interval [CI] = 87.9-93.9) and 72.1 (95% CI = 68.7-75.4), respectively. For HC2, the figures were, respectively, 96.0% (95% CI = 93.9-98.0) and 41.4 (95% CI = 37.7-45.0). The values were high both in women < 30 and ≥ 30 years old (86.9% and 63.3% versus 92.3% and 77.8%, respectively). The addition of a morphological evaluation of the dual-stain-positive cells with establishment of HSIL features as the threshold for a positive reaction increased the specificity (93.5%) but decreased the sensitivity (84.1%).

CONCLUSIONS

Use of the molecular markers p16 and Ki67 has higher specificity than HC2 tests for HSIL or CC, which may support p16/Ki67 dual-staining use in the triage of patients referred for abnormal screening results. Morphological evaluation of p16/Ki67-positive cells may have some benefits in women younger than 30 years or with low-grade squamous intraepithelial lesion.

Impact of p16(INK4a) immunohistochemistry staining on interobserver agreement on the diagnosis of cervical intraepithelial neoplasia

OBJECTIVES

This study aimed to compare the interobserver Cohen κ on H&E staining and on H&E plus p16(INK4a) staining of all cervical biopsy specimens in a population-based screening program.

METHODS

All the colposcopy-guided biopsies generated by the routine screening of 23,258 women aged 25 to 64 years were stained with H&E and H&E plus p16. Biopsy specimens were reviewed by six external experts.

RESULTS

The four diagnoses were available in 441 cases. The interobserver κ values were 0.52 (95% confidence interval [CI], 0.45-0.58) and 0.48 (95% CI, 0.42-0.56) with H&E and H&E + p16, respectively, when using a five-group classification (normal, CIN 1, CIN 2, CIN 3, and cancer); adopting a two-group classification (≤CIN 1 and ≥CIN 2), the values were 0.75 (95% CI, 0.66-0.82) and 0.70 (95% CI, 0.61-0.79), respectively.

CONCLUSIONS

The use of p16 on all cervical biopsy specimens in a screening program showed virtually no effect on reproducibility of the histologic diagnosis.

Variability of Pathologists' Utilization of p16 and Ki-67 Immunostaining in the Diagnosis of Cervical Biopsies in Routine Pathology Practice and Its Impact on the Frequencies of Cervical Intraepithelial Neoplasia Diagnoses and Cytohistologic Correlations

Context.—The use of p16 in cervical biopsies improves the accuracy of cervical intraepithelial neoplasia (CIN) diagnosis and grading and decreases its interpathologist variability.

Objective.—To determine the impact of the frequency of use of p16 immunostains in cervical biopsies on pathologists' diagnoses of CIN grade 1 and grade 2 or above (CIN1 and CIN2+) and on cytohistologic correlations.

Design.—We identified all cervical biopsy specimens with cytologic correlations subjected or not to p16 staining from January 1, 2005, to September 30, 2010; calculated each pathologist's percentage of p16 use; and correlated it with their major cytohistologic discrepancy rates, CIN2+ diagnoses, and CIN1/CIN2+ ratios.

Results.—During the study period, each of the 23 pathologists interpreted 59 to 1811 (mean, 518) of 11 850 cervical biopsy specimens, used p16 for 0% to 21.31% (mean, 10.14%) of these, had CIN2+ detection rates of 9.5% to 24.1% (mean, 18.9%), and CIN1/CIN2+ ratios of 0.7 to 4.5 (mean, 1.5). Compared to the 12 “low users” of p16, who used p16 fewer times than the institution's mean for p16 use, the 11 “high users” of p16 diagnosed more biopsies (8391 versus 3459), had a lower rate of major cytohistologic discrepancies (12.62% versus 14.92%, P &lt; .001), a higher rate of CIN2+ diagnoses (19.9% versus 16.4%, P &lt; .001), a lower range of CIN2+ rates (15.0%–23.1% versus 9.5%–24.1%), and lower CIN1/CIN2+ ratios (1.2 versus 2.3).

Conclusions.—We found a high intrainstitutional variability of p16 use in cervical biopsies, CIN2+ rates, and CIN1/CIN2+ ratios. Use of p16 for greater than 10% of cervical biopsies was associated with improved cytohistologic correlation rates and with lower variability in the frequencies of histologic diagnoses.

New technologies and procedures for cervical cancer screening

The clearly higher sensitivity and reproducibility of human papillomavirus (HPV) DNA testing for high-grade cervical intraepithelial neoplasia (CIN) has led to widespread calls to introduce it as the primary screening test. The main concern has been its lower specificity, due to the fact that it cannot separate transient from persistent infections, and only the latter are associated with an increased risk of high-grade CIN and cancer. Thus, even proponents of HPV testing generally only recommend it for women over the age of 30 years (or in some cases 35 years). If HPV testing is to reach its full potential, new approaches with better specificity are needed, either as triage tests for HPV positive women or, if the high sensitivity of HPV DNA testing can be maintained, as alternate primary screening modalities. Approaches that may useful in this regard, especially as triage tests, include HPV typing, methylation (and consequent silencing) of host and viral genes, and new cytologic methods, such as p16(INK4a) staining, which attempt to identify proliferating cells. At an earlier stage of development are direct methods based on detection of HPV E6 or E7 proteins. Recent progress and current status of these methods is discussed in this chapter. The current status of visual inspection (VIA and VILI) methods is also surveyed and progress on self-sampling is reviewed. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Semantic focusing allows fully automated single-layer slide scanning of cervical cytology slides

Liquid-based cytology (LBC) in conjunction with Whole-Slide Imaging (WSI) enables the objective and sensitive and quantitative evaluation of biomarkers in cytology. However, the complex three-dimensional distribution of cells on LBC slides requires manual focusing, long scanning-times, and multi-layer scanning. Here, we present a solution that overcomes these limitations in two steps: first, we make sure that focus points are only set on cells. Secondly, we check the total slide focus quality. From a first analysis we detected that superficial dust can be separated from the cell layer (thin layer of cells on the glass slide) itself. Then we analyzed 2,295 individual focus points from 51 LBC slides stained for p16 and Ki67. Using the number of edges in a focus point image, specific color values and size-inclusion filters, focus points detecting cells could be distinguished from focus points on artifacts (accuracy 98.6%). Sharpness as total focus quality of a virtual LBC slide is computed from 5 sharpness features. We trained a multi-parameter SVM classifier on 1,600 images. On an independent validation set of 3,232 cell images we achieved an accuracy of 94.8% for classifying images as focused. Our results show that single-layer scanning of LBC slides is possible and how it can be achieved. We assembled focus point analysis and sharpness classification into a fully automatic, iterative workflow, free of user intervention, which performs repetitive slide scanning as necessary. On 400 LBC slides we achieved a scanning-time of 13.9±10.1 min with 29.1±15.5 focus points. In summary, the integration of semantic focus information into whole-slide imaging allows automatic high-quality imaging of LBC slides and subsequent biomarker analysis.

Human papillomavirus genotype distribution in cytologically screened women from northwest Germany

INTRODUCTION

In this study, we evaluate the distribution of 24 human papillomavirus (HPV) genotypes in a cohort of 3,381 cytologically screened women from a rural area of northwest Germany, in correlation to cytological diagnoses and histological outcomes.

MATERIALS AND METHODS

We present a retrospective study in which the HPV-genotyping results of women who attended the German cervical screening program were correlated to cytological diagnosis and histological outcome.

RESULTS

HPV genotyping showed marked differences among cervical lesions. Although HPV-51 was common in all cervical lesions, it was rarely detected as single-type HPV infection in high-grade cervical intraepithelial neoplasia (CIN)3 (2/118 cases). HPV-16 and 18 were more common in CIN3 (57.6%) than in CIN2 (21.8%), but they were absent in 42.4% of all CIN3 lesions in our cohort.

DISCUSSION

Our data show that HPV-16, HPV-31, HPV-51, HPV-53 and HPV-42 are the most prevalent HPV types in the different cervical lesions in this region of northwest Germany. HPV genotyping has been shown to be a powerful tool to triage atypical squamous cells of undetermined significance lesions. Considering the observed heterogeneity of HPV types in CIN2, it could also be useful to triage CIN2+ lesions. Our results underline the usefulness of a morphologically controlled screening program with HPV genotyping as a powerful additional tool.

EUROGIN 2011 roadmap on prevention and treatment of HPV-related disease

The EUROGIN 2011 roadmap reviews the current burden of human papillomavirus (HPV)-related morbidity, as well as the evidence and potential practice recommendations regarding primary and secondary prevention and treatment of cancers and other disease associated with HPV infection. HPV infection causes ~600,000 cases of cancer of the cervix, vulva, vagina, anus and oropharynx annually, as well as benign diseases such as genital warts and recurrent respiratory papillomatosis. Whereas the incidence of cervical cancer has been decreasing over recent decades, the incidence of anal and oropharyngeal carcinoma, for which there are no effective screening programs, has been rising over the last couple of decades. Randomized trials have demonstrated improved efficacy of HPV-based compared to cytology-based cervical cancer screening. Defining the best algorithms to triage HPV-positive women, age ranges and screening intervals are priorities for pooled analyses and further research, whereas feasibility questions can be addressed through screening programs. HPV vaccination will reduce the burden of cervical precancer and probably also of invasive cervical and other HPV-related disease in women. Recent trials demonstrated that prophylactic vaccination also protects against anogenital HPV infection, anogenital intraepithelial lesions and warts associated with vaccine types, in males; and anal HPV infection and anal intraepithelial neoplasia in MSM. HPV-related oropharyngeal cancer could be treated less aggressively because of better survival compared to cancers of the oropharynx unrelated to HPV. Key findings in the field of cervical cancer prevention should now be translated in cost-effective strategies, following an organized approach integrating primary and secondary prevention, according to scientific evidence but adapted to the local situation with particular attention to regions with the highest burden of disease.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology

The terminology for human papillomavirus(HPV)–associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was co-sponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology

The terminology for human papillomavirus (HPV)-associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was cosponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

Endocervical glandular involvement, positive endocervical surgical margin and multicentricity are more often associated with high-grade than low-grade squamous intraepithelial lesion

AIM

The aim of this study was to compare the relative frequencies of endocervical glandular involvement (EGI), multicentricity, positive endocervical surgical margins (ESM) and positive vaginal surgical margins (VSM), and adenocarcinoma in situ of the cervix (AIS) between high-grade and low-grade squamous intraepithelial lesions (HSIL and LSIL, respectively).

MATERIAL AND METHODS

We identified 238 patients with squamous intraepithelial lesions/cervical intraepithelial neoplasia (CIN) who were treated by loop electrocautery excision (LEEP) or conventional cold-knife conization (CKC). A total of 223 (72 [32.3%] LSIL/CIN I; 85 [38.1%] HSIL/CIN II; 66 [29.6%] HSIL/CIN III; and 151 [67.7%], HSIL/CIN II + III) LEEP/CKC slides were histologically reviewed.

RESULTS

The frequencies of EGI, positive ESM, and multicentricity were significantly higher in the HSIL/CIN II + III group than in the LSIL/CIN I group (P = 0.001, 0.001, and 0.025, respectively). Eighteen of the 72 (25%) LSIL/CIN I patients, 44 of the 85 (51.8%) HSIL/CIN II patients, and 60 of the 66 (90.9%) HSIL/CIN III patients (P = 0.001) showed EGI. In four of the 72 (5.6%) LSIL/CIN I patients, 18 of the 85 (21.2%) HSIL/CIN II patients, and 42 of the 66 (63.6%) HSIL/CIN III patients (P = 0.001), ESM was positive. Two of the 72 (2.8%) LSIL/CIN I patients, seven of the 85 (8.2%) HSIL/CIN II patients, and 11 of the 66 (16.7%) HSIL/CIN III patients (P = 0.016) were multicentric.

CONCLUSION

The current study showed that EGI, positive ESM and multicentricity were more often associated with HSIL/CIN II + III than with LSIL/CIN I. Moreover, the frequencies of EGI, multicentricity, and positive ESM increased with increasing severity of the cervical lesion. This result may influence the preference for the type of surgical procedure used for patients with cytological diagnosis of HSIL.

The use of recombinant pseudotype virus-like particles harbouring inserted target antigen to generate antibodies against cellular marker p16INK4A

Protein engineering provides an opportunity to generate new immunogens with desired features. Previously, we have demonstrated that hamster polyomavirus major capsid protein VP1-derived virus-like particles (VLPs) are highly immunogenic and can be employed for the insertion of foreign epitopes at certain surface-exposed positions. In the current study, we have designed pseudotype VLPs consisting of an intact VP1 protein and VP2 protein fused with the target antigen—cellular marker p16^INK4A—at its N terminus. Both proteins coexpressed in yeast were self-assembled to pseudotype VLPs harbouring the inserted antigen on the surface. The pseudotype VLPs were used for generation of antibodies against p16^INK4A that represents a potential biomarker for cells transformed by high-risk human papillomavirus (HPV). The pseudotype VLPs induced in immunized mice a strong immune response against the target antigen. The antisera raised against pseudotype VLPs showed specific immunostaining of p16^INK4A protein in malignant cervical tissue. Spleen cells of the immunized mice were used to generate monoclonal antibodies against p16^INK4A protein. The specificity of antibodies was proven by the immunostaining of HPV-transformed cells. In conclusion, the current study demonstrates the potential of pseudotype VLPs with inserted target antigen as a new type of immunogens to generate antibodies of high diagnostic value.

Decreased D2-40 and increased p16INK4A immunoreactivities correlate with higher grade of cervical intraepithelial neoplasia

BACKGROUND

D2-40 has been shown a selective marker for lymphatic endothelium, but also shown in the benign cervical basal cells. However, the application of D2-40 immunoreactivity in the cervical basal cells for identifying the grade of cervical intraepithelial neoplasia (CIN) has not been evaluated.

METHODS

In this study, the immunoreactive patterns of D2-40, compared with p16(INK4A), which is currently considered as the useful marker for cervical cancers and their precancerous diseases, were examined in total 125 cervical specimens including 32 of CIN1, 37 of CIN2, 35 of CIN3, and 21 of normal cervical tissue. D2-40 and p16(INK4A) immunoreactivities were scored semiquantitatively according to the intensity and/or extent of the staining.

RESULTS

Diffuse D2-40 expression with moderate-to-strong intensity was seen in all the normal cervical epithelia (21/21, 100%) and similar pattern of D2-40 immunoreactivity with weak-to-strong intensity was observed in CIN1 (31/32, 97.2%). However, negative and/or focal D2-40 expression was found in CIN2 (negative: 20/37, 54.1%; focal: 16/37, 43.2%) and CIN3 (negative: 22/35, 62.8%; focal: 12/35, 34.3%). On the other hand, diffuse immunostaining for p16(INK4A) was shown in 37.5% of CIN1, 64.9% of CIN2, and 80.0% of CIN3. However, the immunoreactive pattern of D2-40 was not associated with the p16(INK4A) immunoreactivity.

CONCLUSIONS

Immunohistochemical analysis of D2-40 combined with p16(INK4A) may have a significant implication in clinical practice for better identifying the grade of cervical intraepithelial neoplasia, especially for distinguishing CIN1 from CIN2/3.

Evaluation of CINtec PLUS® testing as an adjunctive test in ASC-US diagnosed SurePath® preparations

The CINtec PLUS® system is an immunohistochemical cocktail composed of antibodies against p16(INK4a) (surrogate of HPV infection) and Ki-67 (proliferation marker) meant to improve the sensitivity and specificity for detecting high-grade dysplasia (HGD). In the presence of dysplasia, a red chromogen marks Ki-67 expression in the nucleus and a brown chromogen marks cytoplasmic p16(INK4a) expression. Only cells showing dual staining are interpreted as positive. This retrospective study examined the performance of CINtec PLUS testing when performed on ASC-US diagnosed samples. Comparison was made to high-risk HPV DNA test results and colposcopic biopsy results. Technical considerations in the interpretation of this immunohistochemical stain are additionally discussed. CINtec PLUS showed modest sensitivity (64%) and specificity (53%) in identifying the presence of HGD at surgical biopsy. Positive and negative predictive values for HGD were 28% and 83%, respectively. HR-HPV DNA test yielded sensitivity of 100% and specificity of 21%. During interpretation, squamous metaplasia and endocervical cells were seen to show individual staining for p16(INK4a) or Ki-67. Individual staining, when present within three dimensional cellular groups common to SurePath® preparations, can be time-intensive to interpret necessitating thoughtful examination at high power. The Pap test with HR-HPV DNA testing is a highly sensitive test. A specific test is needed to prevent false positives and over treatment. The CINtec® system provides a modest increase in specificity beyond HR-HPV DNA testing. Future study of its appropriateness and cost-ffectiveness in a treatment algorithm are warranted.