Accuracy of p16 IHC in Classifying HPV-Driven OPSCC in Different Populations

A Bibliometric Analysis of HPV-Positive Oropharyngeal Squamous Cell Carcinoma from 2000 to 2023

Human-papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-positive OPSCC) is a distinct disease characterized by unique clinical and molecular features compared to HPV-negative OPSCC. A comprehensive bibliometric analysis of HPV-positive OPSCC research was conducted in this study to identify key trends, research hotspots, and emerging frontiers in the field. Data were retrieved from the Web of Science Core Collection database. The distributions of contributors, including countries, institutions, authors, journals, and cooperative networks related to HPV-positive OPSCC, were analyzed and visualized using VOSviewer 1.6.20, CiteSpace 6.3.R1, and the R package Bibliometrix 4.0.0. In addition, the most influential publications and high-frequency keywords were identified and analyzed to discern key topics in this field. A total of 3895 articles and reviews on HPV-positive OPSCC were identified, involving 106 countries, 620 journals, and 18949 authors. The main contributors include the USA (1908 publications), Johns Hopkins University (310 publications), the journal Head and Neck (320 publications), and Erich M. Sturgis (94 publications). The top three keywords are "survival", "radiotherapy", and "p16". There has been a steadily increasing research interest in HPV-positive OPSCC over the last 23 years. Current studies focus on diagnosis, treatment strategies, prognosis, recurrence, and disease surveillance. This bibliometric analysis highlights key contributors and emerging themes, offering insights for future research directions.

Multi-omics insights into the molecular signature and prognosis of hypopharyngeal squamous cell carcinoma

Approximately two-thirds of hypopharyngeal squamous cell carcinoma (HPSCC) cases are diagnosed at advanced stages, with the worst prognosis among head and neck squamous cell carcinomas (HNSCCs). Identifying biomarkers for high-risk patients requiring aggressive treatment is crucial. We present mutational, transcriptomic, and proteomic studies of 103 Chinese HPSCC patients and observe a higher prevalence and poorer prognosis in males. Estrogen response pathways are up-regulated, and proteins phosphorylated by protein kinase C (PKC) and cyclin-dependent kinases (CDKs) are aberrantly regulated in HPSCC. We identify aberrant copy number regions including SOX2(3q26.33), FGFR(8p11.23), CCND1(11q13.3), CDKN2A/2B(9p21.3), and MYC(8q24.21). Human papillomavirus (HPV) status combined with highly mutated genes, such as SYNE1 in HPV(-) and MUC4 in HPV(+) patients, were assessed as prognosis markers. A predictive model involving clinical factors and expression of six genes was established and cross-site validated. These findings open new opportunities for stratifying high-risk patients and molecular targets for personalized therapeutic strategies.

Evolution of testing for the diagnosis of human papillomavirus (HPV) status in head and neck squamous cell carcinoma: Where from and where to?

Human papillomavirus (HPV) is causally associated with head and neck squamous cell carcinomas with the strongest association in the oropharynx. HPV-associated oropharyngeal carcinomas have a different pathogenesis with distinct clinical features and better prognosis than HPV-negative oropharyngeal carcinomas which impacts staging and prognosis. It is, therefore, of clinical significance to accurately determine the HPV status, particularly in oropharyngeal carcinomas. In this review, the different test methods that are used for characterizing HPV status in head and neck squamous cell carcinomas, both conventional methods (p16 immunohistochemistry, HPV DNA in-situ hybridization, HPV DNA PCR, HPV E6/E7 mRNA RT-PCR, HPV RNA in-situ hybridization) as well as emerging novel approaches (HPV circulating tumour DNA, HPV16 E6 antibodies, oral HPV DNA/mRNA PCR), are discussed. Currently, a combined testing approach is favoured, using a sequential strategy of screening with p16 immunohistochemistry and confirming with HPV DNA PCR. HPV RNA in-situ hybridization could potentially serve as a single test owing to its good sensitivity and specificity. The use of liquid biopsies is gaining momentum with HPV circulating tumour DNA as the frontrunner in demonstrating promising clinical utility for early detection in HPV-associated oropharyngeal carcinomas. HPV16 E6 antibodies and oral HPV DNA PCR has potential utility as adjunct tests to aid diagnosis. In this rapidly evolving HPV testing landscape, we as clinicians and laboratorians must evolve and advocate for access to cost-effective accurate HPV testing globally.

Performance analysis of Leica Biosystems p16 monoclonal antibody in oropharyngeal squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cause of cancer death globally, with newly diagnosed oropharyngeal squamous cell carcinoma (OPSCC) cases rising to 54,000 in the US alone in the year 2022. Recently, human papilloma virus (HPV) infection was more prevalent in OPSCC patients than the traditionally known carcinogens such as tobacco or alcohol. HPV 16 is the most common causative HPV strain, which is found in 5-10% of HNSCC patients. HPV 16's E6 and E7 oncoproteins bind and inactivate p53 and retinoblastoma (Rb) tumor-suppressing genes. This causes aberrant over-expression of the cell cycle inhibitor gene, p16, leading to tumorigenesis. Leica Biosystems (LBS) has developed a p16 antibody (6H12 clone) for qualitatively identifying the p16 protein in formalin-fixed paraffin-embedded (FFPE) tissue by immunohistochemical staining. This method comparison study tested the concordance rates between ready-to-use (RTU) LBS p16/LBS RTU p16 antibody and Roche Tissue Diagnostics (RTD) CINtec p16 Histology immunohistochemical (IHC) assays by measuring overall agreement (OA), average positive agreement (APA), and average negative agreement (ANA) rates in 170 OPSCC FFPE cases. Interobserver agreement of the 2 assays and LBS RTU p16 comparison with the standard HPV molecular assays (DNA ISH and PCR) were also assessed.

METHODS

One hundred and seventy (170) unique oropharyngeal cancer cases were stained for qualitative analysis by the LBS p16 antibody on BOND III. This assay was compared to Ventana's RTD E6H4 (CINtec) clone on Benchmark XT. A stained core was considered p16 positive if the Histoscore (H score) was ≥ 140 and negative if H < 140.

RESULTS

Across the pathologists, the agreement rate between the 2 assays ranged from OA, 98.7 - 98.8%, ANA, 98.8 -98.9%, and APA, 98.6%. For LBS RTU p16, the interobserver agreement was OA, 98.7%, ANA, 98.8%, and APA, 98.6%; while for RTD CINtec p16 assay, the concordance was OA, 98.7%, ANA, 98.8% and APA, 98.6%. In comparison to the HPV molecular testing, DNA ISH, and PCR, across pathologists, LBS p16 clone (LBS RTU p16) showed a concordance rate of 85.8-86.9% and 87.6-88.8%, respectively.

CONCLUSION

LBS p16 monoclonal antibody demonstrated high concordance with CINtec p16 IHC assay across all the endpoints, suggesting a potential use of LBS RTU p16 clone in detecting p16 protein in oropharyngeal cancer cases.

Risk Stratification in HPV-Associated Oropharyngeal Cancer: Limitations of Current Approaches and the Search for Better Solutions

The rising incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) necessitates advancements in risk stratification to optimize treatment outcomes and improve the quality of life for patients. Despite its favorable prognosis compared to HPV-negative OPSCC, current clinical staging and biomarkers, such as p16 status, are limited in their ability to distinguish between high- and low-risk patients within HPV-associated OPSCC. This limitation results in the overtreatment of low-risk patients, exposing them to unnecessary toxicity, and the undertreatment of high-risk patients who require more aggressive interventions. This review critically evaluates current stratification methods, including clinical assessments, de-escalation trials, and candidate molecular biomarkers for risk stratification. Emerging approaches such as immune markers, viral genomic integration patterns, and other molecular markers offer promising avenues for enhanced prognostic accuracy. By integrating advanced risk stratification methods, tailored treatment approaches may one day be developed to balance oncologic efficacy with reduced treatment-related morbidity. This review underscores the need for continued research into predictive biomarkers and adaptive treatment strategies to better address the diverse risk profiles of HPV-associated OPSCC patients.

Evaluating Tumor Tissue Modified Viral (TTMV)-HPV DNA for the Early Detection of Anal Squamous Cell Carcinoma Recurrence

BACKGROUND

The incidence and mortality of anal squamous cell carcinoma (ASCC) are rising, with greater than 80% of cases linked to human papillomavirus (HPV), primarily HPV16. Post-treatment surveillance can be challenging due to the limitations of anoscopy, digital anal rectal exam (DARE), and imaging. Plasma tumor tissue modified viral (TTMV)-HPV DNA has shown strong sensitivity, specificity, and predictive value in detecting the recurrence of HPV-driven oropharyngeal cancer. Here, we investigate the ability of TTMV-HPV DNA for the early recurrence detection of ASCC.

METHODS

This retrospective clinical case series included 117 patients with HPV-driven ASCC across 7 U.S. centers, monitored with TTMV-HPV DNA during routine clinical care between March 2020 and June 2024. Physician-reported clinical data and biomarker testing data were combined to create a comprehensive, longitudinal dataset for evaluating test performance metrics.

RESULTS

Patients had a median age of 63 years and median post-diagnosis follow-up of 19 months. HPV status was primarily confirmed by TTMV-HPV DNA (52%) or p16 immunohistochemistry (39%). Of those tested for TTMV-HPV DNA pretreatment, 85% had a positive result. TTMV-HPV DNA clearance during or within three months post-treatment was associated with significantly better recurrence-free survival. The per-patient surveillance sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 82.8%, 98.4%, 96.0%, and 92.5%. Of 24 patients with a documented recurrence and a positive TTMV-HPV DNA test, the test was the first evidence of recurrence in 14 patients (58.3%), with a median lead time of 59 days (range: 10-536). TTMV-HPV DNA accurately resolved 94.3% of cases with indeterminate clinical findings.

CONCLUSIONS

TTMV-HPV DNA testing provides a sensitive and specific approach for detecting patients with recurrent ASCC and resolving the status of patients with indeterminate clinical findings.

Current Evidence on the Relation Between Microbiota and Oral Cancer-The Role of Fusobacterium nucleatum-A Narrative Review

Oral squamous cell carcinoma (OSCC) is one the most prevalent head and neck cancers and represents a major cause of morbidity and mortality worldwide. The main established risk factors for OSCC include tobacco and alcohol consumption and betel quid chewing, which may contribute alone or in combination with other environmental factors to carcinogenesis. The oral microbiota is emerging as a key player in the establishment of the molecular and cellular mechanisms that may trigger or promote carcinogenesis, including in the oral cavity. Among the bacterial species found in the oral microbiota, Fusobacterium nucleatum, an anaerobic bacterium commonly found in oral biofilms and a periodontal pathogen, has gained attention due to solid evidence implicating F. nucleatum in colorectal cancer (CRC). F. nucleatum has been shown to induce chronic inflammation, promote cell proliferation and trigger cellular invasion while deploying immune evasion mechanisms. These experimental findings were first obtained in in vitro and in vivo models of CRC and are being confirmed in studies on OSCC. In this review, we summarize the most recent findings on the role of F. nucleatum in OSCC, discuss the clinical implications in terms of prognosis and provide an overview of the key mechanisms involved. Moreover, we identify research questions and aspects that require investigations to clarify the role of F. nucleatum in OSCC. We anticipate that studies in this emerging field may have a significant clinical impact on the diagnosis, prognosis and management of OSCC.

Role of 18F-FDG PET/CT in Head and Neck Squamous Cell Carcinoma: Current Evidence and Innovative Applications

This article provides an overview of the use of 18F-FDG PET/CT in various clinical scenarios of head-neck squamous cell carcinoma, ranging from initial staging to treatment-response assessment, and post-therapy follow-up, with a focus on the current evidence, debated issues, and innovative applications. Methodological aspects and the most frequent pitfalls in head-neck imaging interpretation are described. In the initial work-up, 18F-FDG PET/CT is recommended in patients with metastatic cervical lymphadenectomy and occult primary tumor; moreover, it is a well-established imaging tool for detecting cervical nodal involvement, distant metastases, and synchronous primary tumors. Various 18F-FDG pre-treatment parameters show prognostic value in terms of disease progression and overall survival. In this scenario, an emerging role is played by radiomics and machine learning. For radiation-treatment planning, 18F-FDG PET/CT provides an accurate delineation of target volumes and treatment adaptation. Due to its high negative predictive value, 18F-FDG PET/CT, performed at least 12 weeks after the completion of chemoradiotherapy, can prevent unnecessary neck dissections. In addition to radiomics and machine learning, emerging applications include PET/MRI, which combines the high soft-tissue contrast of MRI with the metabolic information of PET, and the use of PET radiopharmaceuticals other than 18F-FDG, which can answer specific clinical needs.

p16 Expression in Laryngeal Squamous Cell Carcinoma: A Surrogate or Independent Prognostic Marker?

Laryngeal squamous cell carcinoma (LSCC) is a common malignancy that, despite scientific advancements, has not seen an improvement in its prognosis in the last decades. Few promising predictive markers have been found and none are relevant in clinical practice. p16ink4a, an oncosuppressor protein involved in cell cycle arrest, with a prognostic impact on other cancers, has been widely used in the head and neck region as a surrogate marker of HPV infection. Published papers and recent meta-analyses seem to minimize the biological role of HPV in the context of LSCC's cancerogenesis, and to disprove the reliability of p16ink4a as a surrogate prognostic marker in this context, while still highlighting its potential role as an independent predictor of survival. Unfortunately, the available literature, in particular during the last two decades, is often not focused on its potential role as an independent biomarker and few relevant data are found in papers mainly focused on HPV. The available data suggest that future research should focus specifically on p16ink4a, taking into account both its potential inactivation and overexpression, different patterns of staining, and immunohistochemistry cutoffs, and should focus not on its potential role as a surrogate marker but on its independent role as a predictor of survival.

Sex-specific aspects in patients with oropharyngeal squamous cell carcinoma: a bicentric cohort study

BACKGROUND

Oropharyngeal squamous cell carcinoma (OPSCC) is the only subgroup of head neck cancer that presents with an increased incidence. Gender-specific studies in other cancer entities have revealed differences in treatment response and prognosis. However, only limited data in OPSCC according to gender and human papillomavirus (HPV) status exist. Therefore, we aimed to investigate sex-specific differences in OPSCC and how these may be distributed in relation to HPV and other risk factors.

METHODS

This retrospective, bicentric study included 1629 patients with OPSCC diagnosed between 1992 and 2020. We formed subgroups based on TNM status, American Joint Cancer Committee 8th edition (AJCC8), HPV status, treatment modality (surgery (± radio(chemo)therapy (RCT) vs. definitive RCT) and patient-related risk factors and investigated gender differences and their impact on patients survival via descriptive-,uni- and multivariate analysis.

RESULTS

With the exception of alcohol abuse, no significant differences were found in risk factors between men and women. Females presented with better OS than males in the subgroup T1-2, N + , independent of risk factors (p = 0.008). Males demonstrated significant stratification through all AJCC8 stages (all p < 0.050). In contrast, women were lacking significance between stage II and III (p = 0.992). With regard to therapy (surgery (± R(C)T) - vs. definitive RCT) women treated with surgery had better OS than men in the whole cohort (p = 0.008). Similar results were detected in the HPV-negative OPSCC sub-cohort (p = 0.042) and in high-risk groups (AJCC8 stage III and IV with M0, p = 0.003).

CONCLUSION

Sex-specific differences in OPSCC represent a health disparity, particularly according to staging and treatment, which need to be addressed in future studies.