Comparative Performance of High-Risk Human Papillomavirus RNA and DNA In Situ Hybridization on College of American Pathologists Proficiency Tests

A review of prognostic factors in squamous cell carcinoma of the vulva: Evidence from the last decade

Squamous cell carcinoma of the vulva is a rare gynecologic cancer that is associated with significant patient morbidity and mortality, particularly for recurrent disease. This review summarizes the evidence and continued challenges, regarding the traditional clinicopathologic factors used to prognosticate vulvar squamous cell carcinoma. Articles published within the last 10 years (2010-2020) were identified. Relevant articles concerning the following fifteen prognostic factors were reviewed: HPV/p16 status, vulvar intraepithelial neoplasia, patient age, tumor stage, tumor grade, tumor size, depth of invasion, stromal changes, histologic patterns of invasion, lymphovascular space invasion (LVSI), perineural invasion, lymph node metastases, tumour focality, margin status and lichen sclerosus (LS). The relationship between each prognostic factor and progression-free survival (PFS) and overall survival (OS), including hazard ratios, 95% confidence intervals and p-values, were extracted.

A case of fine-needle aspiration of a neck mass with atypical squamous cells and macrophages

Head and neck lesions often undergo fine-needle aspiration to determine the appropriate management and therapeutic decisions. However, there are numerous diagnostic challenges encountered with these specimens, particularly, if atypical squamous cells are identified. Here, we present a case of an enlarging right neck mass in a 38-year-old female and discuss the diagnostic difficulties and potential pitfalls. Additionally, we review the approach to diagnosis, including differential diagnostic considerations as well as available ancillary testing.

Anal and Perianal Preneoplastic Lesions

Anal cancer, mainly squamous cell carcinoma, is rare but increasing in prevalence, as is its precursor lesion, anal squamous dysplasia. They are both strongly associated with human papillomavirus infection. The 2-tiered Lower Anogenital Squamous Terminology classification, low-grade SIL and high-grade SIL, is preferred to the 3-tiered anal intraepithelial neoplasia classification because of better interobserver agreement and clearer management implications. Immunohistochemistry with p16 is helpful to corroborate the diagnosis of squamous dysplasia. Similarly, immunohistochemistry is helpful to differentiate primary Paget disease from secondary Paget disease, which is usually due to anal squamous mucosal/epidermal involvement by primary rectal adenocarcinoma.

Human Papillomavirus-Associated Oral Epithelial Dysplasia: Report of 5 Illustrative Cases from Latin America

BACKGROUND

Human papillomavirus-associated oral epithelial dysplasia (HPV-OED) is a distinct oral epithelial disorder characterized by viral cytopathic changes caused by transcriptionally active high-risk HPV. The aim of the present study was to report 5 additional cases from Latin America.

METHODS

Clinical data from five patients with HPV-OED were obtained from the archives of three oral pathology services from Brazil and Chile. All cases were submitted to morphological, p16 expression and in situ hybridization (ISH) for HPV analyses.

RESULTS

Four patients were male and one patient was female, with a mean age of 55.4 years. Four patients were HIV seropositive and two were smokers. Three cases affected the buccal mucosa and commissure, one of which had an additional plaque in the soft palate, and one case each occurred on the floor of mouth and lower labial mucosa. Most cases presented as well-demarcated white plaques with a verrucous surface. One case presented multiple lesions ranging from normal to white-colored slightly elevated plaques with a cobblestone surface. Peripheral mucosal pigmentation was observed in two cases. All five cases presented with the characteristic microscopic features of HPV-OED, including severe dysplasia with numerous karyorrhectic and apoptotic cells, full-thickness "block positivity" for p16 and high Ki-67 index (> 90%) sharply demarcated from the adjacent non-dysplastic epithelium. Wide-spectrum DNA ISH-HPV was positive in 4 cases. All patients were treated with conservative surgical excision with no signs of recurrence after a mean of 39-month follow-up.

CONCLUSION

This represents the first series of HPV-OED from Latin America; most cases presented as well-demarcated papillary white plaques affecting the buccal mucosa and commissure of HIV-positive middle-aged men, two of them exhibiting peripheral pigmentation caused by reactive melanocytes. The typical microscopic findings of HPV-OED were observed in all cases, which also showed strong p16 positivity in a continuous band through the full thickness of the epithelium and high Ki67.

HPV Infection in Squamous Cell Carcinoma of the Hypopharynx, Larynx, and Oropharynx With Multisite Involvement

The prevalence and prognostic significance of high-risk human papillomavirus (HR-HPV) have been well-established in oropharyngeal squamous cell carcinoma (OPSCC), but not in hypopharyngeal squamous cell carcinoma (HPSCC) or laryngeal squamous cell carcinoma (LSCC). Moreover, HR-HPV infection in squamous cell carcinoma with multisite involvement has not been examined. To clarify these issues, we retrospectively collected 480 invasive tumors from 467 patients with HPSCC, LSCC, or OPSCC, and comprehensively analyzed the detailed tumor localization, transcriptionally active HR-HPV infection by messenger RNA in situ hybridization, and immunohistochemical staining for p16 and Rb. HR-HPV infection was observed in 115/480 tumors (24%). Human papillomavirus (HPV)-positive cases were closely related with p16 positivity and the partial loss pattern of Rb. HR-HPV was detected in 104 of 161 tumors (64.6%) in the pure OPSCC group and only 1 of 253 tumors (0.4%) in the pure HP/LSCC group; the positive case occurred in the vocal cords. In the multisite-involving combined-type squamous cell carcinoma group, HPV infection was observed in 10/40 (25%) cases, and the 10 HPV-positive cases had OPSCC extending to the larynx or hypopharynx. Among high T-stage (T3/T4) cases of pure OPSCC, HPV-positive cases showed a better prognosis ( P =0.0144), whereas the HPV-positive combined OPSCC group did not show a better prognosis ( P =0.9428), as compared with HPV-negative counterpart. The results suggest that HR-HPV infection in pure HPSCC and LSCC may be extremely rare. HR-HPV infection seems to be present in a substantial proportion of patients with combined OPSCC and HPSCC/LSCC, but it may not improve prognosis at such advanced disease stages. Confirmation of these points awaits future studies with larger cohorts.

High-risk HPV Does not Appear to be an Important Risk Factor for Sinonasal Carcinomas in Turkish Population: A Tertiary Center Experience

Background. The sinonasal tract is the second most common site of human papillomavirus (HPV)-related carcinomas in the head and neck. Published data on the association between sinonasal tumors and HPV are quite inconsistent among different regions. Material and methods. We performed high-risk HPV DNA in situ hybridization (ISH) and p16 immunohistochemistry on sinonasal carcinomas diagnosed between 2006 and 2016. Results. Of 105 sinonasal carcinomas, we found only two (2%) HPV-positive cases; both had non-keratinizing morphology and were diffusely positive for p16. By histologic type, HPV DNA positivity rate was 14% in non-keratinizing squamous cell carcinomas, and we did not detect HPV DNA in any other type of sinonasal carcinomas. Thirteen HPV-negative tumors (7 salivary gland carcinomas, 3 sinonasal undifferentiated carcinomas, 2 keratinizing squamous cell carcinomas, and 1 non-keratinizing squamous cell carcinoma) were positive for p16. In nine carcinomas arising from an underlying sinonasal papilloma, p16 and HPV DNA ISH were evaluated in both carcinoma and papilloma areas and all were negative. Follow-up information was available for 104 patients; 46 (44%) were alive and 58 (55%) died of disease. One of the two HPV-positive patients died of the disease; the other was alive at 100 months of follow-up. Conclusions. We detected a much lower percentage of HPV positivity in sinonasal carcinomas when compared to the literature. We believe that our results support various rates of HPV-related carcinomas depending on the geographic and ethnic characteristics.

Anal intraepithelial neoplasia: a review of terminology, differential diagnoses, and patient management

Despite the knowledge of etiological association with high-risk human papilloma viruses and high-risk patient cohorts, the incidence of anal squamous cell carcinoma has continued to rise. The known precursor lesion (in particular, high-grade squamous intraepithelial lesion) makes it amenable to screening and surveillance strategies. However, the diagnosis of anal intraepithelial neoplasia suffers from interpretation challenges leading to high interobserver variability, along with numerous differential diagnoses and lingering terminology issues. Proper treatment of anal lesions requires accurate diagnosis, and while a variety of modalities are available for treatment, the rate of recurrence remains high and each modality has its own set of side effects and complications. The aim of this review article is to outline the diagnostic considerations and provide practical tips for diagnosing anal squamous intraepithelial lesions.

An insight into clinical and laboratory detections for screening and diagnosis of cervical cancer

INTRODUCTION

Cervical cancer is the most frequent malignancy among women caused by an unresolved long-term infection with distinct human papillomavirus (HPV) genotypes. It is the fourth most common form of cancer among women worldwide. The two oncogenic genotypes, HPV 16 and 18, are responsible for >70% of all cervical cancers worldwide. Cervical cancer is one of the most successfully preventable and treatable forms of cancer if detected early.

AREAS COVERED

In this review article, we have summarizedsummarised the different approaches used in clinical diagnosis and research laboratories to detect HPV-related changes associated with cervical cancer for a better understanding of the advantages and limitations of these tests.

EXPERT OPINION

Despite the well-known screening strategies for cervical cancer, developing nations lack effective implementation due to various factors. With the current rate of cervical cancer cases, precise and timely identification of HPV can significantly impact the prevention and efficient management of cervical cancer. Cervical cancer is the most common gynecological cancer in developing countries. The primary screening test with cytology and molecular testing of HPV is important for preventing cervical cancer. To address these issues, several point-of-care assays have been developed to facilitate rapid screening of HPV with the least turnaround time.

Tumor Cell Extrinsic Synaptogyrin 3 Expression as a Diagnostic and Prognostic Biomarker in Head and Neck Cancer

Over 70% of oropharyngeal head and neck squamous cell carcinoma (HNSC) cases in the United States are positive for human papillomavirus (HPV) yet biomarkers for stratifying oropharyngeal head and neck squamous cell carcinoma (HNSC) patient risk are limited. We used immunogenomics to identify differentially expressed genes in immune cells of HPV(+) and HPV(-) squamous carcinomas. Candidate genes were tested in clinical specimens using both quantitative RT-PCR and IHC and validated by IHC using the Carolina Head and Neck Cancer Study (CHANCE) tissue microarray of HNSC cases. We performed multiplex immunofluorescent staining to confirm expression within the immune cells of HPV(+) tumors, receiver operating characteristic (ROC) curve analyses, and assessed survival outcomes. The neuronal gene Synaptogyrin-3 (SYNGR3) is robustly expressed in immune cells of HPV(+) squamous cancers. Multiplex immunostaining and single cell RNA-seq analyses confirmed SYNGR3 expression in T cells, but also unexpectedly in B cells of HPV(+) tumors. ROC curve analyses revealed that combining SYNGR3 and p16 provides more sensitivity and specificity for HPV detection compared to p16 IHC alone. SYNGR3-high HNSC patients have significantly better prognosis with five-year OS and DSS rates of 60% and 71%, respectively. Moreover, combining p16 localization and SYNGR3 expression can further risk stratify HPV(+) patients such that high cytoplasmic, low nuclear p16 do significantly worse (Hazard Ratio, 8.6; P = 0.032) compared to patients with high cytoplasmic, high nuclear p16. SYNGR3 expression in T and B cells is associated with HPV status and enhanced survival outcomes of HNSC patients.

Squamous and Glandular Lesions of the Vulva and Vagina: What's New and What Remains Unanswered?

A number of changes have been introduced into the 5th Edition of the World Health Organization (WHO) Classification of squamous and glandular neoplasms of the vulva and vagina. This review highlights the major shifts in tumor classification, new entities that have been introduced, recommendations for p16 immunohistochemical testing, biomarker use, molecular findings and practical points for pathologists which will affect clinical care. It also touches upon several issues that still remain answered in these rare but undeniably important women's cancers.

HPV-related head and neck cancers: Pathology and biology

Discovering the key role HPV plays in head and neck carcinogenesis has revolutionized our approach to cancers such as oropharyngeal carcinomas. As the role of HPV expands beyond the oropharynx, there is a pursued need to understand the oncogenic mechanisms of HPV-driven tumorigenesis and their implications. Optimizing HPV detection methods all while acknowledging their limitations will ensure our ability to diagnose HPV-driven neoplasia wherever clinically relevant.

Application of the Roche Cobas® HPV 4800 in Formalin-Fixed, Paraffin-Embedded Samples for Head and Neck Squamous Cell Carcinomas

Testing for high risk human papillomavirus (HR-HPV) status is standard of care in squamous cell carcinomas of the oropharynx as well as cervical lymph node squamous cell carcinomas of unknown primary origin. DNA or RNA in-situ hybridization (ISH) and p16 immunohistochemistry, widely used currently for HPV detection are operator-dependent. In addition, DNA ISH has a relatively low sensitivity, and p16 is not entirely specific for HR-HPV infection. In this study, we examined the performance of the cobas® HPV genotyping assay in formalin-fixed, paraffin-embedded (FFPE) samples of head and neck squamous cell carcinoma. FFPE samples from head neck and other anatomic sites tested by ISH and p16 for HR-HPV at ARUP Laboratories were selected for this study. Samples were deparaffinized, stained and micro-dissected for tumor contents followed by tissue lysis, then tested with cobas® for HR-HPV. All the samples were also tested by HPV Linear Array for confirmation. All (N = 18) high risk HPV positive specimens tested by cobas® were confirmed as positive by the Linear Array test. All the specimens tested as negative by cobas® were tested as negative (N = 5) or positive only for low risk HPV (N = 3) by Linear Array, as cobas® only detects HR HPV. Limits of detection for HPV16 and 18 were established at 160-320 and 320-1600 copies, respectively. Our data suggest that cobas® HR-HPV genotyping is a viable option for detection of HR-HPV in formalin-fixed, paraffin-embedded samples from head and neck and other anatomic sites and has been validated for clinical use.

p16 overexpression and Rb loss correlate with high-risk HPV infection in oropharyngeal squamous cell carcinoma

AIMS

p16 is a sensitive surrogate marker for transcriptionally active high-risk human papillomavirus (HR-HPV) infection in oropharyngeal squamous cell carcinoma (OPSCC), but it is not sufficient in all clinical settings.

METHODS AND RESULTS

We examined the p16 and Rb expression status in 177 OPSCC cases by immunohistochemistry and the presence of transcriptionally active HR-HPV infection by mRNA in-situ hybridisation. The 177 cases were divided into p16⁺ /HPV⁺ (n = 105, 59.3%), p16⁺ /HPV^- (n = 8, 4.5%) and p16^- /HPV^- (n = 64, 36.2%) groups. The p16⁺ /HPV^- and p16^- /HPV^- groups had a trend towards worse overall survival (OS) or significantly worse OS than the p16⁺ /HPV⁺ group (n = 105) (P = 0.0610, P = 0.0004, respectively). We divided the Rb status into preserved expression (> 90%, n = 68), partial loss (PL) (10-90%, n = 97) and complete loss (CL) (< 10%, n = 12). Among the HPV-positive cases (n = 105), the Rb pattern was typically PL (n = 97, 92.4%) and rarely CL (n = 8, 7.6%), but never preserved expression (0%). In contrast, among the HPV-negative cases (n = 72), the Rb pattern was typically preserved expression (n = 68, 94.4%) and rarely CL (n = 4, 5.6%), but never PL (0%). Compared to p16 alone, the combination of p16 overexpression and Rb-PL/CL showed equally excellent sensitivity (each 100%) and improved specificity (97.2 versus 88.9%) and positive predictive values (98.1 versus 92.9%).

CONCLUSIONS

These results suggest that the combined use of p16 and Rb immunohistochemistry could be a reliable, cost-effective method to predict HR-HPV infection in OPSCCs; however, HPV specific testing is necessary on inconclusive cases. We propose a diagnostic algorithm for practical use of these markers.

RB1, p16, and Human Papillomavirus in Oropharyngeal Squamous Cell Carcinoma

While P16 immunohistochemistry (IHC) is a well-established surrogate marker of Human Papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (OSCC), Retinoblastoma 1 (RB1) loss may lead to p16 overexpression in the absence of HPV. We determined the proportion of p16-positive/HPV-negative OSCC with RB1 loss and other alterations in RB1/p16 pathway, and tested RB1 IHC as a prognostic biomarker for OSCC, along with the 8th edition of AJCC staging manual. P16 and RB1 IHC and HPV DNA in situ hybridization (ISH) were performed on 257 OSCC. High risk HPV RNA ISH, RB1 fluorescence in situ hybridization (FISH), and next generation sequencing (NGS) were done on p16-positive/HPV DNA ISH-negative OSCC. Disease free survival (DFS) was used as an endpoint. In the entire cohort and in p16-positive (n = 184) and p16-negative (n = 73) subgroups, AJCC 8th edition staging correlated with DFS (p < 0.01). RB1 IHC showed RB1 loss in p16-positive OSCC only (79/184, 43%). RB1 loss by IHC is associated with a better DFS, without providing additional prognostic information for patients with p16-positive OSCC. HPV RNA ISH was positive in 12 of 14 HPV DNA ISH-negative cases. RB1 IHC showed loss in 10 of 15 HPV DNA ISH-negative cases and in 1 of 2 HPV RNA ISH-negative cases. Overall, only one case of p16-positive/HPV RNA ISH-negative OSCC showed RB1 loss by IHC (1/184, 0.5%). Of the 10 p16-positive and HPV DNA ISH-negative cases with RB1 loss by IHC, 2 had RB1 hemizygous deletion and 3 showed Chromosome 13 monosomy by FISH. No RB1 mutations were detected by NGS. Other molecular alterations in p16-positive/HPV DNA ISH-negative cases included TP53 and TERT mutations and DDX3X loss. HPV-independent RB1 inactivation rarely results in false positive p16 IHC. RB1 inactivation by high risk HPV E7 oncoprotein may co-exist with RB1 deletion. RB1 loss is a favorable prognosticator and occurs exclusively in p16-positive OSCC. The 8th edition of the AJCC staging manual satisfactorily predicts DFS of OSCC patients.

Correlation of transcriptionally active human papillomavirus status with the clinical and molecular profiles of head and neck squamous cell carcinomas

BACKGROUND

To examine the molecular profiles of human papillomavirus (HPV)-positive and HPV-negative head and neck squamous cell carcinomas (HNSCCs), expression of epidermal growth factor receptor (EGFR), phospho-EGFR dimers, hypoxia markers, and cancer stem cell markers were evaluated.

METHODS

HPV-status was confirmed using RNA-ISH. Immunohistochemical data of biomarker expression levels were analyzed using the Mann-Whitney U test. The clinical outcomes and biomarker expression in the HPV-positive (n = 25), matched HPV-negative (n = 49), and p16-positive/HPV-negative (n = 20) subgroups were comparatively analyzed.

RESULTS

HPV was detected in 25 (5.8%) cases and was significantly associated with favorable outcomes. HPV-positive tumors exhibited lower membrane expression of EGFR, pEGFRY1068, pEGFRY1173, CD44, CD44v6, and CD98hc than HPV-negative and p16-positive tumors. The expression of HIF1α, CA9, ALDH1A1, and SOX2 was not significantly associated with HPV-status. The clinical outcomes and biomarker expression levels were similar between the HPV-negative and p16-positive HNSCC.

CONCLUSION

HPV-positive HNSCC exhibited distinct molecular profile compared to HPV-negative and p16-positive HNSCC. The clinical and molecular profiles were similar between p16-positive and HPV-negative subgroups.

Human Papillomavirus Testing in Head and Neck Squamous Cell Carcinoma: Impact of the 2018 College of American Pathologists Guideline Among Referral Cases at a Large Academic Institution

CONTEXT.—

Given the growing clinical significance of human papillomavirus status in oropharyngeal squamous cell carcinoma, the College of American Pathologists established a set of evidence-based recommendations for high-risk human papillomavirus testing.

OBJECTIVE.—

To evaluate the impact of the recommendations on human papillomavirus ancillary test ordering habits by comparing compliance before and after the guideline was published.

DESIGN.—

We retrospectively reviewed head and neck squamous cell carcinoma biopsy or resection specimens from outside institutions during a 2.5-year period around guideline publication for whether or not human papillomavirus testing was performed in accordance with the guideline.

RESULTS.—

Human papillomavirus testing deviated from the guideline in 45 of 107 cases (42.1%) before and 93 of 258 cases (36.0%) after their publication (P = .29). This included 6 of 26 cases of oropharyngeal squamous cell carcinoma (23.1%) before and 5 of 55 cases (9.1%) after (P = .16), with 5 of 5 (100.0%) after due to not performing p16 immunohistochemistry. This also included 30 of 68 cases of nonoropharyngeal carcinoma (44.1%) before and 69 of 163 (42.3%) after the guideline was published (P = .88), with 29 of 30 (96.7%) before and 67 of 69 (97.1%) after due to unnecessary use of p16 immunohistochemistry. Nodal metastasis testing deviated in 9 of 13 cases (69.2%) before and 19 of 40 cases (47.5%) after (P = .21) with marked variability in testing, including 3 of 9 (33.3%) before and 8 of 19 (42.1%) after, for not confirming certain p16 immunohistochemistry-positive tumors with human papillomavirus-specific testing.

CONCLUSIONS.—

Pathologists continue to deviate from the testing guideline significantly in everyday practice. Further education and discussion about the appropriate handling of head and neck cancer specimens may be needed.

Quantitative assessment of p16 expression in FNA specimens from head and neck squamous cell carcinoma and correlation with HPV status

BACKGROUND

This study investigated p16 by immunohistochemistry (IHC) on cellblocks (CBs) and human papillomavirus (HPV) by polymerase chain reaction (PCR) in fine-needle aspiration (FNA) of head and neck squamous cell carcinoma (HNSCC).

METHODS

Receiver operating characteristic (ROC) curve analysis was used to assess test performance in CBs compared with p16 IHC in 42 surgical specimens from patients with HNSCC and in correlation with HPV by PCR in cytology specimens. The study assessed HPV by PCR in FNA specimens as a substitute for p16 IHC in surgical specimens.

RESULTS

Of 42 cases, 38 CBs showed malignant cells as cohesive clusters of viable cells with or without single tumor cells, whereas 4 specimens were composed exclusively of single tumor cells and degenerated cells. All p16-negative surgical specimens showed an absence of p16 staining in the corresponding CBs (n = 16). In the p16-positive surgical cases (n = 26), corresponding CBs with tumor clusters (n = 23) showed heterogeneous p16 expression ranging from 40% to 100%; however, scoring single cells was challenging and unreliable because of cellular degradation. ROC curve inspection showed the optimal threshold to be at least 40% p16 staining in tumor clusters with 100% sensitivity and specificity. In cases with inadequate CBs, HPV by PCR on needle rinse showed 88% sensitivity and 100% specificity for p16 expression in surgical specimens.

CONCLUSIONS

A cutoff of at least 40% p16 expression in tumor clusters may be appropriate for p16 positivity in cytology CB specimens. A positive HPV finding by PCR on needle rinse can be used as a substitute for p16 expression in surgical specimens.

HPV Detection in Head and Neck Squamous Cell Carcinomas: What Is the Issue?

Besides classic tobacco and alcohol risk factors, human papillomavirus (HPV) plays a role in the development of a subset of head and neck squamous cell carcinomas (HNSCCs), and notably oropharynx squamous cell carcinomas (OPSCCs). HPV-induced OPSCCs have a different biological behavior and a better prognosis compared to non-HPV-induced OPSCCs and the eighth-edition TNM classification now separates these two entities. Therefore, determining the HPV status of patients with OPSCC is now essential for treatment, prognosis, and development of clinical trials. In this review, after reminding essential steps of HPV implication in the cell cycle, we describe the existing tools that are currently feasible in routine practice according to facilities available in health structures, with their benefits and drawbacks: HPV PCR, E6/E7 mRNA RT-PCR, E6/E7 mRNA in situ hybridization, HPV DNA in situ hybridization, and P16 immunochemistry. Besides these traditional HPV detection tools, novel diagnostic approaches are being evaluated for HPV-induced OPSCC “ultrastaging.” E6 humoral response and ddPCR-detecting HPVct DNA are two techniques performed on blood and are therefore non-invasive. Baseline E6 humoral levels could have a prognostic value, and HPVct DNA could be helpful for HPV OPSCC recurrence monitoring. At last, next-generation sequencing (NGS)-based “capture HPV” is a technique feasible on biopsies and circulating DNA material. It helps characterize HPV integration status and sites, and it could define prognostic subgroups in HPV-induced OPSCC. These novel precision detection tools could be further integrated in the care of patients with HPV-induced OPSCC.

A review of prognostic factors in squamous cell carcinoma of the vulva: Evidence from the last decade

Squamous cell carcinoma of the vulva is a rare gynecologic cancer that is associated with significant patient morbidity and mortality, particularly for recurrent disease. This review summarizes the evidence and continued challenges, regarding the traditional clinicopathologic factors used to prognosticate vulvar squamous cell carcinoma. Articles published within the last 10 years (2010-2020) were identified. Relevant articles concerning the following fifteen prognostic factors were reviewed: HPV/p16 status, vulvar intraepithelial neoplasia, patient age, tumor stage, tumor grade, tumor size, depth of invasion, stromal changes, histologic patterns of invasion, lymphovascular space invasion (LVSI), perineural invasion, lymph node metastases, tumour focality, margin status and lichen sclerosus (LS). The relationship between each prognostic factor and progression-free survival (PFS) and overall survival (OS), including hazard ratios, 95% confidence intervals and p-values, were extracted.

Evaluation of human papillomavirus (HPV) prediction using the International Endocervical Adenocarcinoma Criteria and Classification system, compared to p16 immunohistochemistry and HPV RNA in-situ hybridization

Background

The International Endocervical Adenocarcinoma Criteria and Classification (IECC) separated endocervical adenocarcinomas into human papillomavirus (HPV) associated (HPVA) and non–HPV-associated (NHPVA) categories by morphology alone. Our primary objective was to assess the accuracy of HPV prediction by the IECC system compared to p16 immunohistochemistry and HPV RNA in-situ hybridization (RISH). Our secondary goal was to directly compare p16 and HPV RISH concordance.

Methods

Cases were classified by IECC and stained for p16 and HPV RISH on tissue microarray, with discordant p16/HPV RISH cases re-stained on whole tissue sections. Remaining discordant cases (p16/HPV, IECC/p16, IECC/HPV discordances) were re-reviewed by the original pathologists (n = 3) and external expert pathologists (n = 2) blinded to the p16 and HPV RISH results. Final IECC diagnosis was assigned upon independent agreement between all reviewers.

Results

One hundred and eleven endocervical adenocarcinomas were classified originally into 94 HPVA and 17 NHPVA cases. p16 and HPV RISH was concordant in 108/111 cases (97%) independent of the IECC. HPV RISH and p16 was concordant with IECC in 103/111 (93%) and 106/111 (95%), respectively. After expert review, concordance improved to 107/111 (96%) for HPV RISH. After review of the eight discordant cases, one remained as HPVA, four were reclassified to NHPVA from HPVA, two were unclassifiable, and one possibly represented a mixed usual and gastric-type adenocarcinoma.

Conclusions

p16 and HPV RISH have excellent concordance in endocervical adenocarcinomas, and IECC can predict HPV status in most cases. Focal apical mitoses and apoptotic debris on original review led to the misclassification of several NHPVA as HPVA.