Usefulness of p16ink4a, ProEX C, and Ki-67 for the Diagnosis of Glandular Dysplasia and Adenocarcinoma of the Cervix Uteri:

Triage options for positive high-risk HPV results from HPV-based cervical cancer screening: a review of the potential alternatives to Papanicolaou test cytology

The American Cancer Society has recommended high-risk human papillomavirus (HPV) testing as the primary screening method for cervical cancer since 2020. Up to this point, the transition from Pap test cytology-based screening or co-testing with cytology and HPV testing has been slow and limited. However, more health systems in the United States are in the process of implementing this change. The transition to HPV-based screening requires a triage strategy for positive results. Genotyping to specifically detect HPV types 16 and 18 in conjunction with reflex cytology for the remaining high-risk HPV genotypes has been the recommended method. Testing options including Dual Stain for p16/Ki-67 and extended HPV genotyping are currently being incorporated into treatment algorithms as alternatives. Methylation testing is another promising method extensively investigated around the world. This review, performed by members of the Clinical Practice Committee of the American Society of Cytopathology, examines the rationale behind the switch away from reliance on Pap test cytology in the cervical cancer screening algorithm and the opportunities and problems associated with the most promising alternative approaches. Published studies that give insight into the performance characteristics of these newer tests are reviewed. At the present time, Pap test cytology remains a viable triage option for positive HPV screening results, but alternative tests have significant appeal and should be considered in tandem with the decision to offer primary HPV screening.

Pitfalls in Gynecological Cytology: Review of the Common and Less Frequent Entities in Pap Test

BACKGROUND

Pitfalls in Pap test could be defined as false positive, false negative, or underdiagnosed results which can lead to unnecessary diagnostic procedures or delayed and inadequate treatment. It can be a consequence of misinterpretation of certain morphological entities which are described in this paper.

SUMMARY

The paper presents an overview of the morphological features and look-alikes of the common sources of pitfalls such as atrophy, repair, intrauterine device change, tubal metaplasia, hyperchromatic crowded groups, and radiation changes. Rare causes of pitfalls such as Arias-Stella changes, pemphigus, tumor diathesis per se, rare types of cervical cancer, including verrucous and papillary squamous cell cancer, gastric type, and endometrioid adenocarcinoma are also described.

KEY MESSAGES

The awareness of pitfalls in cervical cytology is important for cytopathologists and clinicians to avoid future errors. Review of Pap tests with erroneous diagnosis is important for quality control in cytology laboratory, and it must be considered an educational- and experience-building procedure. Cytopathologist should not pull back in significant diagnoses, especially in human papillomavirus-negative cases.

Diagnostic value of p16 and Ki-67 expression in cervical glandular intraepithelial disease: A review

OBJECTIVES

Cervical adenocarcinoma has been increasing in frequency, particularly among young women. Its diagnosis still presents many challenges. In addition to the difficulty in accessing the lesion, the lack of well-established criterias for cytological and histological diagnosis, and colposcopic images that are often not very clear, there are many benign situations that mimic glandular diseases. Immunohistochemistry has been used to aid this diagnosis. The purpose of this review is to evaluate the data available in the literature related to the use of p16 and Ki-67 as an auxiliary tool in the diagnosis of glandular disease.

METHODS

Original articles were searched in the PUBMED/MEDLINE, EMBASE, SCOPUS and BVS using different combinations of keywords and descriptors.

RESULTS

Of the 83 initial articles, 10 were selected. The criterias used for immunohistochemical interpretation showed many differences. The studies compared benign pathologies to malignant pathologies and some used panels with different immunomarkers while others used only p16. P16 showed an intense staining pattern in malignant pathologies, despite some studies have shown a negative pattern in adenocarcinoma. This can be explained by the histological subtype, not always related to HPV. Some studies have shown immunopositivity for p16 in normal tissues, tubal metaplasia and cervical endometriosis, but the staining pattern was never intense, as in malignant tissues. Ki-67 showed a more intense staining in AIS and adenocarcinoma tissues and was also present in normal tissues, mainly in tubal metaplasia and cervical endometriosis.

CONCLUSIONS

Biomarkers have proved to be important tools in aiding the diagnosis of glandular lesions, either alone or in panels. Standardization in the interpretation of immunochemistry is required.

The Evolving Spectrum of Precursor Lesions of Cervical Adenocarcinomas

Modern classification schemes divide cervical adenocarcinomas into human papillomavirus (HPV)-associated and HPV-independent types. The precursor lesions of the former are well known and comprise HPV-associated (usual/endocervical) adenocarcinoma in situ (AIS) and the much less common stratified mucin-producing intraepithelial lesion (SMILE). The precursor lesions of HPV-independent cervical adenocarcinomas are much less well known, although postulated precursors of gastric-type adenocarcinoma include atypical lobular endocervical glandular hyperplasia and gastric-type AIS. In this review, we cover HPV-associated and HPV-independent precursor lesions of cervical adenocarcinomas concentrating on diagnostic criteria (morphology and immunophenotype) and differential diagnosis. We propose a uniform terminology and diagnostic criteria for precursor lesions showing intestinal differentiation with goblet cells because this may be a feature of both HPV-associated and HPV-independent AIS.

Characterization and clinical validation of MCM2 and TOP2A monoclonal antibodies in the BD ProEx™ C assay: An immunoassay which detects aberrant S-phase induction in cervical tissue

BACKGROUND

The Papanicolaou (Pap) screen has been successful in reducing cervical cancer; but exhibits low sensitivity when detecting cervical dysplasia. Use of molecular biomarkers in Pap tests may improve diagnostic accuracy.

DESIGN

Monoclonal antibodies to Minichromosome Maintenance Protein 2 (MCM2) and DNA Topoisomerase II α (TOP2A) were selected for use in IHC based on their ability to differentiate normal from diseased cervical tissues in tissue microarrays. Enhanced Green Fluorescent Protein Western blot analysis was used to help identify binding epitopes specific to MCM2 and TOP2A antibody clones. Antibody affinity was determined by solution phase affinity measurement and immunohistochemistry was performed using high affinity MCM2 or TOP2A antibodies on serial histological sections.

RESULTS

Antibody clones to MCM2 and TOP2A clones were selected based on their ability to detect over expression in abnormal cervical epithelia. In IHC, MCM2-27C5.6 and MCM2-26H6.19 demonstrated superior staining in abnormal cervical tissue over the MCM2-CRCT2.1 antibody. A combination of MCM2 and TOP2A antibodies showed greater staining when compared to staining with any of the antibodies alone on serial histological sections. Distinct linear epitopes were elucidated for each of the MCM2 and TOP2A clones. Affinity values (Kd) for MCM2 or TOP2A antibodies had a similar range. In a research study, the MCM2 and TOP2A (BD ProEx™ C) antibody cocktail showed increased epithelia staining with increasing dysplasia. The use of BD ProEx™ C in combination with H&E staining enhanced immunohistochemical discrimination of dysplastic and non-dysplastic FFPE cervical tissue specimens.

CONCLUSIONS

BD ProEx™ C containing MCM2 and TOP2A antibodies showed strong specific nuclear staining that correlated with increased dysplasia and lesion severity. Enhanced performance of the antibodies was linked to their unique topography recognition. BD ProEx™ C incorporates antibodies that enhance detection of CIN2+ cervical disease.

[S3 guidelines on diagnostics and treatment of cervical cancer: Demands on pathology]

Between 2011 and the end of 2014 the former consensus S2k guidelines for the diagnostics and treatment of cervical cancer were updated and upgraded to S3 level, methodologically based on the regulations of the German Cancer Society (DKG). The present article summarizes the relevant aspects for the sectioning, histopathological workup, diagnostics and reporting for the pathology of invasive cancer of the uterine cervix. The recommendations are based on the most recent World Health Organization (WHO) and TNM classification systems and consider the needs of the clinician for appropriate surgical and radiotherapeutic treatment of patients. Detailed processing rules of colposcopy-guided diagnostic biopsies, conization and trachelectomy as well as for radical hysterectomy specimens and lymph node resection (including sentinel lymph node resection) are given. In the guidelines deep stromal invasion in macroinvasive cervical cancer is defined for the first time as tumor infiltration of > 66% of the cervical stromal wall. Furthermore, morphological prognostic factors for microinvasive and macroinvasive cervical cancer are summarized.

Cytological Diagnoses of Adenocarcinoma in situ of the Cervix: Common Misdiagnoses

OBJECTIVE

In routine screening, glandular lesions have high false-negative and false-positive rates. Our study sought to improve the cytological diagnoses and differentiation of glandular lesions.

STUDY DESIGN

A total of 24 cytology slides were retrospectively reviewed. Among these slides, 15 were confirmed via histology to have varying amounts of adenocarcinoma in situ (AIS) components. The other 9 cytology slides exhibited AIS mimics that had been originally considered to be AIS or atypical glandular cells (AGCs) and were selected for differentiation from AIS.

RESULTS

Overall, 12 of the 15 cytological slides exhibited significant atypical glandular features that met the criteria for AIS. However, the original cytological diagnoses included 2 cases of AIS, 3 AGCs-favor neoplasia (AGC-FN), 2 AGCs, 1 case that was not otherwise specified (AGC-NOS), 1 NILM (negative for intraepithelial lesion and malignancy), 3 HSILs (high-grade squamous intraepithelial lesions), and 2 ASC-Hs (atypical squamous cells, cannot exclude HSIL). The latter 9 cytological slides were subsequently histologically confirmed to be 2 metaplasias, 2 reactive lesions, 1 decidual change, 3 serous adenocarcinomas, and 1 SCNEC (small-cell neuroendocrine carcinoma).

CONCLUSION

Cytological screening will be valuable for identifying glandular lesions as effectively as squamous lesions if the doubly high false rates can be decreased.

Advancing rapid point-of-care viral diagnostics to a clinical setting

ABSTRACT 

We discuss here critical factors in ensuring the success of a viral diagnostic at the point of care. Molecular and immunoassay approaches are reviewed with a focus on their ability to meet the infrastructure and workflow limitations in clinical settings in both the developed and developing world. In addition to being low cost, easy-to-use, accurate and adapted for the intended laboratory and healthcare environment, viral diagnostics must also provide information that appropriately directs clinical treatment decisions. We discuss the challenges and implications of linking diagnostics to clinical decision-making at the point of care using three examples: respiratory viruses in the developed world, differential fever diagnosis in the developing world and HPV detection in resource-limited settings.

The spectrum of cervical glandular neoplasia and issues in differential diagnosis

CONTEXT

Premalignant and malignant glandular lesions of the cervix are known to often cause diagnostic problems with a variety of benign (more common) as well as other malignant mimics, the latter setting often being represented by secondary involvement by endometrioid endometrial carcinoma especially in small samplings.

OBJECTIVE

To highlight key histologic features and immunohistochemical markers that may be helpful in the distinction of in situ endocervical carcinoma from benign glandular proliferations, and those that separate different subtypes of invasive endocervical carcinoma, as well as invasive carcinoma from other carcinomas secondarily involving the cervix and nonneoplastic proliferations of the cervix.

CONCLUSIONS

Clinical and morphologic features as well as immunohistochemistry results should be used in conjunction in the differential diagnosis of glandular proliferations of the cervix, as correct interpretation has major clinical consequences for the patient in most instances (especially benign versus malignant). Immunohistochemical markers should be used as part of a panel of antibodies, as exceptions may occur to the usual pattern of staining, and if used singly, they may mislead the pathologist to establish a wrong diagnosis.

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.

Utility of ProExC and IMP3 immunocytochemical staining in atypical glandular cells of undetermined significance in liquid-based cervical cytology

The diagnosis of atypical glandular cells of undetermined significance (AGUS) in liquid-based cervical cytology specimens shows significant underlying pathology in only 30% of cases, while the remaining cases are found to be benign (reactive, reparative/metaplastic). Previous studies have reported positive ProExC and IMP3 staining in neoplastic glandular lesions of the uterine cervix and corpus. We present our experience with the utility of these markers in the evaluation of AGUS cases in liquid-based cervical cytology. The case cohort included 34 cases diagnosed as AGUS. ProExC and IMP3 immunocytochemical (ICC) stains were performed on ThinPrep® slides and the results correlated with subsequent biopsy findings. Positive expression was classified as strong diffuse nuclear immunostaining for ProExC and granular cytoplasmic for IMP3. The presence of AGUS cells on the ICC stained slides was confirmed in all cases. IMP3 was positive in 80% of glandular neoplasms and negative in 93% non-glandular lesions/cases negative for squamous intraepithelial lesion (SIL). ProExC was positive in 60% of glandular neoplasms and negative in 83% non-glandular lesions/cases negative for SIL. When used as a panel (ProExC + IMP3), at least one stain was positive in 100% of glandular neoplasm cases and they were both negative in 83% of non-glandular lesions/cases negative for SIL. Based on this study, both ProExC and IMP3, when used as an immuno panel, can predict the presence of glandular lesions on subsequent biopsies and can serve as an aid in the diagnosis and management of AGUS cases.

CINtec PLUS immunocytochemistry as a tool for the cytologic diagnosis of glandular lesions of the cervix uteri

Cytologic findings of glandular lesions of the cervix uteri are often difficult to evaluate. We studied the usefulness of CINtec PLUS p16/Ki-67 double stain (mtm laboratories, Heidelberg, Germany) for the diagnosis of glandular lesions. The study included 47 abnormal results on liquid-based cytologic tests with a subsequent histologic diagnosis of adenocarcinoma in situ or with early invasion, and 16 samples with negative results on follow-up. All samples were stained with CINtec PLUS p16/Ki-67 double stain. Of the neoplastic samples, 7 were excluded because of insufficient residual cellularity or loss of neoplastic cells. Of the samples that were adequate, 92.5% were stained with CINtec PLUS, whereas 7.5% were judged inconclusive. All inconclusive cases were at least 3 years old. Of the 16 negative samples, 15 (93.8%) stained negative and only 1 (6.2%) showed several positive clusters of cells. Our study shows that CINtec PLUS is a robust and useful tool for the diagnosis of glandular lesions of the cervix uteri.

Methylomic analysis identifies frequent DNA methylation of zinc finger protein 582 (ZNF582) in cervical neoplasms

Background

Despite of the trend that the application of DNA methylation as a biomarker for cancer detection is promising, clinically applicable genes are few. Therefore, we looked for novel hypermethylated genes for cervical cancer screening.

Methods and Findings

At the discovery phase, we analyzed the methylation profiles of human cervical carcinomas and normal cervixes by methylated DNA immunoprecipitation coupled to promoter tiling arrays (MeDIP-on-chip). Methylation-specific PCR (MSP), quantitative MSP and bisulfite sequencing were used to verify the methylation status in cancer tissues and cervical scrapings from patients with different severities. Immunohistochemical staining of a cervical tissue microarray was used to confirm protein expression. We narrowed to three candidate genes: DBC1, PDE8B, and ZNF582; their methylation frequencies in tumors were 93%, 29%, and 100%, respectively. At the pre-validation phase, the methylation frequency of DBC1 and ZNF582 in cervical scraping correlated significantly with disease severity in an independent cohort (n = 330, both P<0.001). For the detection of cervical intraepithelial neoplasia 3 (CIN3) and worse, the area under the receiver operating characteristic curve (AUC) of ZNF582 was 0.82 (95% confidence interval  = 0.76–0.87).

Conclusions

Our study shows ZNF582 is frequently methylated in CIN3 and worse lesions, and it is demonstrated as a potential biomarker for the molecular screening of cervical cancer.

Role of protein biomarkers in the detection of high-grade disease in cervical cancer screening programs

Since the Pap test was introduced in the 1940s, there has been an approximately 70% reduction in the incidence of squamous cell cervical cancers in many developed countries by the application of organized and opportunistic screening programs. The efficacy of the Pap test, however, is hampered by high interobserver variability and high false-negative and false-positive rates. The use of biomarkers has demonstrated the ability to overcome these issues, leading to improved positive predictive value of cervical screening results. In addition, the introduction of HPV primary screening programs will necessitate the use of a follow-up test with high specificity to triage the high number of HPV-positive tests. This paper will focus on protein biomarkers currently available for use in cervical cancer screening, which appear to improve the detection of women at greatest risk for developing cervical cancer, including Ki-67, p16^INK4a, BD ProEx C, and Cytoactiv HPV L1.