Evaluation of human papilloma virus diagnostic testing in oropharyngeal squamous cell carcinoma: sensitivity, specificity, and prognostic discrimination

Accuracy of Salivary Circulating Tumor Human Papillomavirus DNA in Detecting Oropharyngeal Cancer: A Systematic Review and Meta-analysis

Importance

Circulating tumor human papillomavirus DNA (ctHPV DNA) has shown potential as a biomarker capable of improving outcomes in patients with HPV-related oropharyngeal (OP) cancer. It can be isolated from plasma or saliva, with the latter offering reduced invasiveness and theoretic reduction of lead time.

Objective

To perform a systematic review and meta-analysis on the accuracy of salivary ctHPV DNA for detecting HPV-associated OP cancer.

Data Sources

Cochrane Library, Embase, PubMed, and Web of Science databases were searched from inception through October 2023.

Study Selection

All patients who underwent salivary ctHPV DNA testing at presentation for possible or diagnosed HPV-related OP cancer were included. Non-English and review publications were excluded. Two authors independently voted on article inclusion with a third resolving conflicting votes.

Data Extraction and Synthesis

Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines, multiple authors independently abstracted data and assessed bias of included articles. Bivariate random-effects meta-analysis was performed with I2 to assess for study heterogeneity.

Main Outcomes and Measures

Sensitivities, specificities, positive likelihood ratios (PLR), negative likelihood ratios (NLR), and diagnostic odds ratios (DOR) with 95% CIs alongside area under the curve (AUC) of a summary receiver operating characteristic (SROC) curve were calculated. The initial analysis took place throughout December 2023.

Results

Of 440 initially identified articles, 6 met inclusion criteria and demonstrated moderate heterogeneity (I2 = 36%) with low risk of bias and low applicability concerns. Overall, 263 total patients were included with a median (range) age of 58 (39-86) years, and 228 (87%) were male patients. Per updated prognostic staging criteria, localized tumors (ie, stages 1 or 2) comprised most cancers at 139 (77%), whereas advanced ones (ie, stages 3 or 4) comprised the remaining 41 (23%). Pooled sensitivity, specificity, PLR, NLR, and DOR values were 64% (95% CI, 36%-85%), 89% (95% CI, 46%-99%), 11.70 (95% CI, 0.37-77.00), 1.21 (95% CI, 0.08-7.00), and 139.00 (95% CI, 0.05-837.00), respectively. The AUC of the SROC curve was 0.80.

Conclusions and Relevance

This study supports salivary ctHPV DNA as an acceptably specific test in detecting HPV-associated OP cancer that would benefit from testing in clinical trials prior to real-time implementation.

Human papillomavirus and p16INK4a in oropharyngeal squamous cell carcinomas: A systematic review and meta-analysis

We intended to update human papillomavirus (HPV) prevalence and p16INK4a positivity in oropharyngeal squamous cell carcinomars (SCC), and calculate HPV attributable fraction (AF) for oropharyngeal SCC by geographic region. We searched Medline, Embase, and the Cochrane Library to identify published studies of HPV prevalence and p16INK4a positivity alone or together in oropharyngeal SCC before December 28, 2021. Studies that reported type-specific HPV DNA prevalence using broad-spectrum PCR-based testing methods were included. We estimated pooled HPV prevalence, type-specific HPV prevalence, and p16INK4a positivity. AF of HPV was calculated by geographic region. One hundred and thirty-four studies including 12 139 cases were included in our analysis. The pooled HPV prevalence estimate for oropharyngeal SCC was 48.1% (95% confidence interval [CI] 43.2-53.0). HPV prevalence varied significantly by geographic region, and the highest HPV prevalence in oropharyngeal SCC was noted in North America (72.6%, 95% CI 63.8-80.6). Among HPV positive cases, HPV 16 was the most common type with a prevalence of 40.2% (95% CI 35.7-44.7). The pooled p16INK4a positivity in HPV positive and HPV16 positive oropharyngeal SCC cases was 87.2% (95% CI 81.6-91.2) and 91.7% (84.3-97.2). The highest AFs of HPV and HPV16 were noted in North America at 69.6% (95% CI 53.0-91.5) and 63.0% (48.0-82.7). [Correction added on 31 October 2023, after first online publication: the percentage symbol (%) was missing and has been added to 63.0% (48.0-82.7) in the Abstract and Conclusion.] A significant proportion of oropharyngeal SCC was attributable to HPV. HPV16 accounts for the majority of HPV positive oropharyngeal SCC cases. These findings highlight the importance of HPV vaccination in the prevention of a substantial proportion of oropharyngeal SCC cases.

The Prediction of Biological Features Using Magnetic Resonance Imaging in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Magnetic resonance imaging (MRI) is an indispensable, routine technique that provides morphological and functional imaging sequences. MRI can potentially capture tumor biology and allow for longitudinal evaluation of head and neck squamous cell carcinoma (HNSCC). This systematic review and meta-analysis evaluates the ability of MRI to predict tumor biology in primary HNSCC. Studies were screened, selected, and assessed for quality using appropriate tools according to the PRISMA criteria. Fifty-eight articles were analyzed, examining the relationship between (functional) MRI parameters and biological features and genetics. Most studies focused on HPV status associations, revealing that HPV-positive tumors consistently exhibited lower ADCmean (SMD: 0.82; p < 0.001) and ADCminimum (SMD: 0.56; p < 0.001) values. On average, lower ADCmean values are associated with high Ki-67 levels, linking this diffusion restriction to high cellularity. Several perfusion parameters of the vascular compartment were significantly associated with HIF-1α. Analysis of other biological factors (VEGF, EGFR, tumor cell count, p53, and MVD) yielded inconclusive results. Larger datasets with homogenous acquisition are required to develop and test radiomic-based prediction models capable of capturing different aspects of the underlying tumor biology. Overall, our study shows that rapid and non-invasive characterization of tumor biology via MRI is feasible and could enhance clinical outcome predictions and personalized patient management for HNSCC.

Etiology, diagnosis, treatment, and prevention of human papilloma virus-associated oropharyngeal squamous cell carcinoma

Classical oropharyngeal squamous cell carcinoma (OPSCC) caused by alcohol consumption and smoking and HPV-associated OPSCC caused by human papillomavirus (HPV) infection have different etiologies, incidences, and prognoses. Therefore, the 8th American Joint committee on Cancer (AJCC) and Union for International Cancer Control (UICC) TNM classifications propose distinguishing HPV-associated OPSCC from classical OPSCC and classifying it as an independent disease. Therefore, this review provides an overview of HPV-associated OPSCC from the perspectives of epidemiology, carcinogenesis, development, diagnosis, treatment, and prevention. The incidence of HPV-associated OPSCC is increasing. Although HPV vaccination has been shown to be effective at reducing the incidence of cervical cancer, it is still unclear how it affects the incidence of HPV-associated OPSCC. Additionally, the prognosis of patients with HPV-associated OPSCC is extremely favorable compared to that of patients with classical OPSCC. Therefore, patients with HPV-associated OPSCC may undergo reduced-dose therapy, although attempts to reduce treatment intensity should be carefully planned to ensure they do not compromise oncological outcomes, and large-scale trials aimed at reducing treatment intensity are ongoing.

Prognostic value and cost benefit of HPV testing for oropharyngeal cancer patients

OBJECTIVES

High-risk human papillomavirus (HR-HPV) can cause oropharyngeal squamous cell carcinoma (OpSCC). The revised 8th edition of the AJCC Staging Manual now stages OpSCC by incorporating p16 immunohistochemistry (IHC), the surrogate marker for HPV status. This study assessed the prognostic values of p16 and HPV markers.

METHODS

We identified 244 OpSCC patients diagnosed between 2000 and 2008 from the British Columbia Cancer Registry with enough tissue to conduct experiments. Formalin-fixed, paraffin-embedded tissue sections were stained for p16 IHC, RNA in situ hybridization (ISH) HPV 16 and 18, and DNA ISH HR-HPV. Electronic charts were reviewed to collect clinical and outcome data. Combined positive RNA and/or DNA ISH was used to denote HPV status.

RESULTS

Human papillomavirus was positive among 77.9% of samples. Using HPV as the benchmark, p16 IHC had high sensitivity (90.5%), but low specificity (68.5%). Distinct subgroups of patients were identified by sequential separation of p16 then HPV status. Among both p16-positive and p16-negative groups, HPV-positive patients were younger, more males, and had better clinical outcomes, especially 5-year overall survival. We further evaluated the technical costs associated with HPV testing.

CONCLUSION

Human papillomavirus is more prognostic than p16 for OpSCC. Clinical laboratories can adopt HPV RNA ISH for routine analysis.

Localization and characterization of human papillomavirus-16 in oral squamous cell carcinoma

OBJECTIVES

The role of Human papillomavirus (HPV) in the oral squamous cell carcinoma (OSCC) has not been completely elucidated. The purpose of the present study was to investigate the prevalence and localization of HPV-16 virus in OSCC and to correlate HPV-16 positivity and p16INK4A expression with the clinical and pathological features of OSCC.

METHODS

The archives of Oral Pathology at the University of Florida, College of Dentistry were accessed for demographic, clinical, histopathological data, and slides of 114 OSCC patients. HPV-16 positivity of OSCC was evaluated by p16INK4A immunohistochemistry (IHC) and HPV-16 E6/E7mRNA by in situ hybridization (ISH).

RESULTS

Out of 114 consecutive pathological slides of OSCC, 16 samples (14%) showed positivity for p16INK4A by IHC and 14 samples (12%) were positive for HPV-16 E6/E7mRNA ISH and the Positivity showed a significant correlation with the patients' age, alcohol consumption, and the degree of OSSC differentiation. The hard palate showed the highest positivity of p16INK4A IHC and HPV-16 mRNA ISH (38%, 36% respectively).

CONCLUSION

HPV-16 is a significant factor in oral carcinogenesis. We recommend using p16INK4A as a surrogate marker for HPV detection in OSCC, which can be complemented by RNA ISH for the identification of HPV subtypes.

The Prevalence of HPV in Oral Cavity Squamous Cell Carcinoma

Human papillomavirus (HPV) is an important risk factor in a subset of head and neck squamous cell carcinomas (HNSCC), but the association with oral cavity squamous cell carcinomas (OCSCC) remains controversial. This study aimed to identify the prevalence of HPV infection in OCSCC. A systematic search on PubMed and EMBASE was performed, including articles assessing the prevalence of HPV-positive (HPV+) OCSCC published from January 2017 to December 2022. OCSCC was considered HPV+ by the detection of HPV DNA, HPV RNA, and/or p16 overexpression in the tumor mass. A meta-analysis was made determining the overall HPV+ OCSCC prevalence. We included 31 studies comprising 5007 patients from 24 countries. The study size ranged from 17 to 940 patients. The HPV+ OCSCC proportion variated widely and ranged from 0% to 37%. Tumors in the tongue were the predominant sublocation for HPV in the oral cavity. The meta-analysis revealed that the overall HPV+ OCSCC prevalence is 6% (95% CI; 3-10%), and only one study found HPV and OCSCC significantly associated. Thus, HPV may not be a necessary or a strong risk factor in OCSCC oncogenesis, and the possibility of a site misclassification of a mobile tongue with the root of the tongue cannot be excluded.

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

High-risk human papillomavirus (HPV) infection is a defined etiopathogenetic factor in oropharyngeal carcinogenesis with a clear prognostic value. The P16 IHC (immunohistochemistry) is a widely accepted marker for HPV-driven carcinogenesis in oropharyngeal squamous cell carcinoma (OPSCC); in the present paper, we discuss its reliability as a standalone marker in different populations. The literature suggests that rates of p16 IHC false positive results are inversely correlated with the prevalence of HPV-driven carcinogenesis in a population. We propose a formula that can calculate such a false positive rate while knowing the real prevalence of HPV-driven OPSCCs in a given population. As it has been demonstrated that p16 positive/HPV negative cases (i.e., false positives at p16 IHC) have the same prognosis as p16 negative OPSCC, we conclude that despite the valuable prognostic value of p16 IHC, relying only on a p16 IHC positive result to recommend treatment de-intensification could be risky. For this aim, confirmation with an HPV nucleic acid detection system, especially in areas with a low prevalence of HPV-related OPSCCs, should be pursued.

Recommendations for the use of biomarkers for head and neck cancer, including salivary gland tumours: A Consensus of the Spanish Society of Medical Oncology and the Spanish Society of Pathology

The treatment of head and neck and salivary gland tumours is complicated and is constantly evolving. Prognostic and predictive indicators of response to treatment are enormously valuable for designing individualized therapies, which justifies their research and validation. Some biomarkers, such as p16, Epstein-Barr virus, PD-L1, androgen receptors and HER-2, are already used routinely in clinical practice. These biomarkers, along with other markers that are currently under development, and the massively parallel sequencing of genes, ensure future advances in the treatment of these neoplasms. In this consensus, a group of experts in the diagnosis and treatment of tumours of the head and neck and salivary glands were selected by the Spanish Society of Pathology (Sociedad Española de Anatomía Patológica - SEAP) and the Spanish Society of Medical Oncology (Sociedad Española de Oncología Médica - SEOM) to evaluate the currently available information and propose a series of recommendations to optimize the determination and daily clinical use of biomarkers.

The Prognostic and Predictive Effects of Human Papillomavirus Status in Hypopharyngeal Carcinoma: Population-Based Study

BACKGROUND

The role of the Human Papillomavirus (HPV) status in patients with hypopharyngeal squamous cell carcinoma (HSCC) remains controversial.

OBJECTIVE

Our aim was to determine the prognostic and predictive effects of HPV status in patients with locally advanced HSCC (stage III-IVB) receiving primary radiotherapy.

METHODS

Patients diagnosed with stage III-IVB HSCC between 2010 and 2016 were identified. HPV status, demographics, clinicopathological characteristics, treatment, and survival data were captured. Kaplan-Meier analysis, multivariable Cox regression analysis, and propensity score matching analysis were performed.

RESULTS

We identified 531 patients in this study and 142 (26.7%) patients with HPV-positive diseases. No significant differences were observed between those with HPV-negative and HPV-positive diseases with regard to demographics, clinicopathological characteristics, and chemotherapy use. HPV-positive HSCC had better head and neck cancer-specific survival (HNCSS; P=.001) and overall survival (OS; P<.001) compared to those with HPV-negative tumors. Similar results were found using the multivariable Cox regression analysis. Sensitivity analyses showed that the receipt of chemotherapy was associated with significantly improving HNCSS (P<.001) and OS (P<.001) compared to not receiving chemotherapy in HPV-negative HSCC, whereas comparable HNCSS (P=.59) and OS (P=.12) were found between both treatment arms in HPV-positive HSCC. Similar results were found after propensity score matching.

CONCLUSIONS

Approximately one-quarter of HSCC may be HPV-related, and HPV-positive HSCC is associated with improved survival outcomes. Furthermore, additional chemotherapy appears to be not related to a survival benefit in patients with HPV-positive tumors who received primary radiotherapy.

Value of p53 sequencing in the prognostication of head and neck cancer: a systematic review and meta-analysis

This review aimed to examine the relationship between TP53 mutational status, as determined by genomic sequencing, and survival in squamous cell carcinoma of the head and neck. The databases Medline, Embase, Web of Science (core collection), Scopus and Cochrane Library were searched from inception to April 2021 for studies assessing P53 status and survival. Qualitative analysis was carried out using the REMARK criteria. A meta-analyses was performed and statistical analysis was carried out to test the stability and reliability of results. Twenty-five studies met the inclusion criteria, of which fifteen provided enough data for quantitative evaluation. TP53 mutation was associated with worse overall survival (HR 1.75 [95% CI 1.45-2.10], p < 0.001), disease-specific survival (HR 4.23 [95% CI 1.19-15.06], p = 0.03), and disease-free survival (HR 1.80 [95% CI 1.28-2.53], p < 0.001). Qualitative assessment identified room for improvement and the pooled analysis of all anatomical subsites leads to heterogeneity that may erode the validity of the observed overall effect and its subsequent extrapolation and application to individual patients. Our systematic review and meta-analysis supports the utility of TP53 mutational as a prognostic factor for survival in head and neck squamous cell carcinoma. A well designed prospective, multi-centre trial is needed to definitively answer this question.

HPV Enhances HNSCC Chemosensitization by Inhibiting SERPINB3 Expression to Disrupt the Fanconi Anemia Pathway

Head and neck squamous cell carcinoma (HNSCC) is the most common malignant tumor of the head and neck, and the prognosis of patients is poor due to chemotherapeutic resistance. Interestingly, patients with HNSCC induced by human papillomavirus (HPV) infection are more sensitive to chemotherapy and display a better prognosis than HPV-negative patients. The biological relevance of HPV infection and the mechanism underlying chemosensitivity to cisplatin remain unknown. Herein, SERPINB3 is identified as an important target for regulation of cisplatin sensitivity by HPV-E6/E7 in HNSCC. Downregulation of SERPINB3 inhibits cisplatin-induced DNA damage repair and enhances the cytotoxicity of cisplatin. In detail, decreasing SERPINB3 expression reduces the USP1-mediated deubiquitination of FANCD2-FANCI in the Fanconi anemia pathway, thereby interfering with cisplatin-induced DNA interstrand crosslinks repair and further contributing to HNSCC cell apoptosis. To translate this finding, pH-responsive nanoparticles are used to deliver SERPINB3 small interfering RNA in combination with cisplatin, and this treatment successfully reverses cisplatin chemotherapeutic resistance in a patient-derived xenograft model from HPV-negative HNSCC. Taken together, these findings suggest that targeting SERPINB3 based on HPV-positive HNSCC is a potential strategy to overcome cisplatin resistance in HPV-negative HNSCC and improves the prognosis of this disease.

Recommendations for the use of biomarkers for head and neck cancer, including salivary gland tumours: a consensus of the Spanish Society of Medical Oncology and the Spanish Society of Pathology

The treatment of head and neck and salivary gland tumours is complicated and evolves constantly. Prognostic and predictive indicators of response to treatment are enormously valuable for designing individualized therapies, which justifies their research and validation. Some biomarkers, such as p16, Epstein-Barr virus, PD-L1, androgen receptors and HER-2, are already used routinely in clinical practice. These biomarkers, along with other markers that are currently under development, and the massively parallel sequencing of genes, ensure future advances in the treatment of these neoplasms. In this consensus, a group of experts in the diagnosis and treatment of tumours of the head and neck and salivary glands were selected by the Spanish Society of Pathology (Sociedad Española de Anatomía Patológica-SEAP) and the Spanish Society of Medical Oncology (Sociedad Española de Oncología Médica-SEOM) to evaluate the currently available information and propose a series of recommendations to optimize the determination and daily clinical use of biomarkers.

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.

Low Prevalence of HPV Related Oropharyngeal Carcinogenesis in Northern Sardinia

HPV infection is a clear etiopathogenetic factor in oropharyngeal carcinogenesis and is associated with a markedly better prognosis than in smoking- and alcohol-associated cases, as specified by AJCC classification. The aim of the present work is to evaluate the prevalence of HPV-induced OPSCC in an insular area in the Mediterranean and to assess the reliability of p16 IHC (immunohistochemistry) alone, as accepted by AJCC, in the diagnosis of HPV-driven carcinogenesis in such a setting. All patients with OPSCC consecutively managed by the referral center in North Sardinia of head and neck tumor board of AOU Sassari, were recruited. Diagnosis of HPV-related OPCSS was carried out combining p16 IHC and DNA testing on FFPE samples and compared with the results of p16 IHC alone. Roughly 14% (9/62) of cases were positive for HPV-DNA and p16 IHC. Three more cases showed overexpression of p16, which has a 100% sensitivity, but only 75% specificity as standalone method for diagnosing HPV-driven carcinogenesis. The Cohen’s kappa coefficient of p16 IHC alone is 0.83 (excellent). However, if HPV-driven carcinogenesis diagnosed by p16 IHC alone was considered the criterion for treatment deintensification, 25% of p16 positive cases would have been wrongly submitted to deintensified treatment for tumors as aggressive as a p16 negative OPSCC. The currently accepted standard by AJCC (p16 IHC alone) harbors a high rate of false positive results, which appears risky for recommending treatment deintensification, and for this aim, in areas with a low prevalence of HPV-related OPSCC, it should be confirmed with HPV nucleic acid detection.

Effect of p16 Status on Survival Outcomes in Sinonasal Squamous Cell Carcinoma

OBJECTIVE

Evaluate the effect of p16 status on disease-free survival (DFS) and overall survival (OS) in patients with sinonasal squamous cell carcinoma (SCC) undergoing treatment with curative intent; and to assess how p16 status may affect patterns of recurrence.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary medical center.

METHODS

Patients with sinonasal SCC treated with curative intent from 2012 to 2018 were identified. Independent variable of interest was p16 status, which was assessed using immunohistochemistry (IHC) with a 70% staining cutoff for positivity. Kaplan Meier survival curve was plotted to assess correlation between p16 status and DFS and OS. Association between recurrence patterns and p16 status was conducted using chi square and fisher's exact tests. Multivariable Cox proportional hazard analysis was conducted to assess association between independent variables and DFS.

RESULTS

Fifty patients with sinonasal SCC met inclusion criteria. Patients were p16 positive in 28/50 (56%) of cases. Kaplan Meier survival curve revealed no statistically significant association between p16 status and DFS or OS survival (P = .780, P = .474). There was no difference in recurrence patterns in patients with p16 positive versus negative tumors.

CONCLUSION

p16 status did not have prognostic value on DFS and OS in our cohort of patients with sinonasal SCC undergoing treatment with curative intent. There was no difference in recurrence patterns between the 2 populations. Based on the results of this study, p16 status should not impact counseling of patients as it relates to their prognosis from SNM.

The effect of human papillomavirus status on prognosis and local treatment strategies of T1-2N0 oropharyngeal squamous cell cancer

Purpose

To explore the effect of human papillomavirus (HPV) status on prognosis and further investigate whether human papillomavirus (HPV) status has an impact on the local treatment strategies for T1-2N0 oropharyngeal squamous cell cancer (OPSCC) patients.

Methods

Patients diagnosed with T1-2N0 OPSCC between 2010 and 2015 were included from the Surveillance, Epidemiology, and End Results database. Data were analyzed using propensity score matching (PSM), Chi-square test, Kaplan-Meier survival analysis, and Cox multivariable analyses.

Results

A total of 1,004 patients were identified, of whom 595 (59.3%) had HPV-related tumors. Of all the patients, 386 (38.4%) and 618 (61.6%) received definitive radiotherapy and radical surgery, respectively. HPV status had no significant effect on local treatment strategies for early-stage OPSCC (P = 0.817). The 3-year cancer-specific survival (CSS) and overall survival (OS) were 89.6 and 80.1%, respectively. Compared to those with HPV-negative diseases, patients with HPV-positive diseases had better CSS and OS. A total of 222 pairs of patients were completely matched after PSM. The results of multivariate Cox regression analysis showed that patients with HPV-positive disease had significantly better CSS (P = 0.001) and OS (P < 0.001) compared to those with HPV-negative tumors. However, local treatment strategy was not associated with survival outcomes after PSM (CSS, P = 0.771; OS, P = 0.440). The subgroup analysis showed comparable CSS and OS between those treated with radical surgery and definitive radiotherapy regardless of HPV status.

Conclusions

HPV status is an independent prognostic factor for the survival of stage T1-2N0 OPSCC patients. Local treatment strategies had no significant effect on the survival of early-stage OPSCC regardless of HPV status. Patients with early-stage OPSCC should be informed regarding the pros and cons of definitive radiotherapy or radical surgery.

Oncogenic KPNA2 Serves as a Biomarker and Immune Infiltration in Patients With HPV Positive Tongue Squamous Cell Carcinoma

Human tongue squamous cell carcinoma (TSCC), the most prevalent type of oral cancer, is associated with human papillomavirus (HPV) infection. Our previous work showed Karyopherin α2 (KPNA2), as an oncogene of TSCC, by relegating the p53/autophagy signaling pathway. Nevertheless, the significance of KPNA2 in TSCC pathogenesis has not been established. KPNA2 levels were evaluated via the TCGA database, and its effects on survival outcomes were assessed by LASSO, Kaplan‐Meier, and COX regression analyses. CIBERSORT and ESTIMATE investigated the relationships between KPNA2 and immune infiltration. At the same time, KPNA2 and HPV infection was analyzed by immunohistochemistry. In addition, the association between downstream molecular regulation pathways and KPNA2 levels was determined by GO, GSEA, and WGCNA. In TSCC, KPNA2 levels were associated with clinical prognosis and tumor grade. Moreover, KPNA2 may be involved in cancer cell differentiation and facilitates tumor-related genes and signaling pathways, such as Cell Cycle, Mitotic G1 phase, G1/S transition, DNA Repair, and Transcriptional Regulation TP53 signaling pathways. Nevertheless, regulatory B cells, follicular helper B cells, and immune and stromal scores between low- and high-KPNA2 expression groups were insignificant. These results imply that KPNA2 is highly involved in tumor grade and prognosis of TSCC. KPNA2 levels correct with HPV 16 markedly regulated cell differentiation, several oncogenes, and cancer‐related pathways.

Clinical impact of p16 positivity in nasopharyngeal carcinoma

Purpose

The clinical characteristics and prognosis of HPV‐related nasopharyngeal cancer (NPC) remain controversial. The relationship between p16 status and outcome was retrospectively investigated in the NPC patients.

Materials and Methods

Between May 2009 and May 2019, 81 NPC patients who received definitive radiation therapy, in a hospital in Japan, were identified and the prognosis was investigated. p16, p53, and Epstein–Barr virus (EBV) status were assessed. Also, circumferential tumor extent in the nasopharyngeal cavity was assessed on a 5‐point scale.

Results

Nine and 72 patients were p16‐positive and p16‐negative, respectively. Fewer patients were EBV‐encoded RNA in situ hybridization (EBER‐ISH)‐positive in the p16‐positive group than in the p16‐negative group (p < .01). Seventy‐five patients were nonkeratinizing NPCs, and six patients were keratinizing NPCs. There were two p16‐positive patients among the keratinizing NPCs.

The mean circumferential tumor extent scores of 16‐positive and p16‐negative NPCs were 4.2 and 3.2, respectively with a statistically significant difference (p = .02). Two‐year progression‐free survival (PFS) of p16‐positive and p16‐negative patients undergoing chemoradiation therapy were 100% and 69%, respectively (p = .13).

Conclusion

In this study conducted in Japan, p16‐positive NPC patients are minor but not very low, and the proportion of keratinizing NPCs was small. p16‐positive NPCs were seen both in keratinizing and nonkeratinizing NPCs. P16‐positive NPC had a tendency of better PFS than p16‐negative NPC. This better prognosis might be due to the higher radiosensitivity of the p16‐positive cell. Additionally, p16‐positive NPCs seemed to spread more extensively in circumference along the nasopharyngeal mucosa than p16‐negative NPCs.

Longitudinal measurement of HPV copy number in cell-free DNA is associated with patient outcomes in HPV-positive oropharyngeal cancer

INTRODUCTION

Oropharyngeal squamous cell carcinoma (OPSCC) is increasing in global prevalence and is divided into two types dependent on association with human papillomavirus (HPV). Assay of HPV copy number in plasma cell-free DNA (cfDNA) provides a minimally invasive method for detecting and monitoring tumour-derived HPV, with potential for enhancing clinical care.

MATERIALS AND METHODS

In a prospectively recruited cohort of 104 OPSCC patients, we evaluate the utility of cfDNA droplet digital PCR (ddPCR) as a method for characterisation and longitudinal monitoring of patients with OPSCC.

RESULTS

ddPCR assay of pre-treatment plasma cfDNA for five HPV types showed overall 95% concordance with p16 immunohistochemistry and PCR analysis of tumour tissue. Longitudinal sampling in 48 HPV+ve patients, with median follow-up of 20 months, was strongly associated with patient outcomes. Persistently elevated cfDNA-HPV post-treatment was associated with treatment failure (2/2 patients) and an increase of cfDNA-HPV in patients whose HPV levels were initially undetectable post-treatment was associated with disease recurrence (5/6 patients). No recurrence was observed in patients in whom cfDNA-HPV was undetectable in all post-treatment samples. In two patients, sequential HPV measurement could have avoided surgical intervention which did not confirm recurrence.

CONCLUSION

The high concordance of pre-treatment plasma cfDNA-HPV analysis with tissue-based assays, together with the clinical associations of sequentially measured post-treatment cfDNA-HPV copy number add to a growing body of evidence that suggest utility of cfDNA-HPV ddPCR in management of OPSCC. Standardised clinical trials based on these data are now needed to assess the impact of such testing on overall patient outcomes.

Prognostic value of human papillomavirus detection and the eighth edition of the TNM classification staging system in oropharyngeal squamous cell carcinoma: A single-center Polish study

OBJECTIVES

This study aimed to determine human papillomavirus (HPV) status and genotypes, the HPV status-dependent survival, and the applicability of the eighth TNM classification in Polish patients diagnosed with oropharyngeal squamous cell carcinoma (OPSCC).

STUDY DESIGN

All patients with primary OPSCC, diagnosed and treated from 2007 to 2017 at the National Research Institute of Oncology, Warsaw, Poland, who underwent radical radiotherapy were included. The Kaplan-Meier method was deployed to produce 3- and 5-year observed survival (OS) estimates.

RESULTS

A total of 110 OPSCC cases were identified. Double positivity for HPV (IHC p16^INK4a and HPV-DNA) was recorded in 70.9% of cases, with HPV16 being the most prevalent genotype (96.2%). The disease stage was significantly less advanced in the HPV-related group than in the HPV-negative group (P < .001). Three- and 5-year OS in HPV-related carcinoma was 80.7% and 74.0%, respectively; in the HPV-negative group, OS was 52.9% and 48.5%. OS rates were associated with HPV status, tumor stage, and disease stage according to the eighth edition TNM classification.

CONCLUSIONS

The majority of Polish patients with OPSCC are HPV16-positive. In HPV-related OPSCC, survival rates are significantly higher than in HPV-negative OPSCC. The findings support the requirement of HPV testing in Polish patients with OPSCC because HPV-positive status influences tumor prognosis.

The impact of radiomics for human papillomavirus status prediction in oropharyngeal cancer: systematic review and radiomics quality score assessment

Purpose

Human papillomavirus (HPV) status assessment is crucial for decision making in oropharyngeal cancer patients. In last years, several articles have been published investigating the possible role of radiomics in distinguishing HPV-positive from HPV-negative neoplasms. Aim of this review was to perform a systematic quality assessment of radiomic studies published on this topic.

Methods

Radiomics studies on HPV status prediction in oropharyngeal cancer patients were selected. The Radiomic Quality Score (RQS) was assessed by three readers to evaluate their methodological quality. In addition, possible correlations between RQS% and journal type, year of publication, impact factor, and journal rank were investigated.

Results

After the literature search, 19 articles were selected whose RQS median was 33% (range 0–42%). Overall, 16/19 studies included a well-documented imaging protocol, 13/19 demonstrated phenotypic differences, and all were compared with the current gold standard. No study included a public protocol, phantom study, or imaging at multiple time points. More than half (13/19) included feature selection and only 2 were comprehensive of non-radiomic features. Mean RQS was significantly higher in clinical journals.

Conclusion

Radiomics has been proposed for oropharyngeal cancer HPV status assessment, with promising results. However, these are supported by low methodological quality investigations. Further studies with higher methodological quality, appropriate standardization, and greater attention to validation are necessary prior to clinical adoption.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00234-022-02959-0.

HPV-associated oropharyngeal cancer: epidemiology, molecular biology and clinical management

Human papillomavirus (HPV)-positive (HPV⁺) oropharyngeal squamous cell carcinoma (OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the UICC/AJCC staging system separates HPV⁺ OPSCC from its HPV-negative (HPV⁻) counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment de-intensification as a means to improve quality of life while maintaining acceptable survival outcomes. In addition, owing to the distinct biology of HPV⁺ OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage owing to a lack of symptoms in the early stages; therefore, a need exists to identify and validate possible diagnostic biomarkers to aid in earlier detection. In this Review, we provide a summary of the epidemiology, molecular biology and clinical management of HPV⁺ OPSCC in an effort to highlight important advances in the field. Ultimately, a need exists for improved understanding of the molecular basis and clinical course of this disease to guide efforts towards early detection and precision care, and to improve patient outcomes.

The incidence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is increasing rapidly in most developed countries. In this Review, the authors provide an overview of the epidemiology, molecular biology and treatment of HPV-positive OPSCC, including discussions of the role of treatment de-escalation and emerging novel therapies.

The incidence of human papillomavirus-associated oropharyngeal cancer (HPV⁺ OPSCC) is expected to continue to rise over the coming decades until the benefits of gender-neutral prophylactic HPV vaccination begin to become manifest.

The incidence of HPV⁺ OPSCC appears to be highest in high-income countries, although more epidemiological data are needed from low- and middle-income countries, in which HPV vaccination coverage remains low.

The substantially better prognosis of patients with HPV⁺ OPSCC compared to those with HPV^– OPSCC has been recognized in the American Joint Committee on Cancer TNM8 staging guidelines, which recommend stratification by HPV status to improve staging.

The molecular biology and genomic features of HPV⁺ OPSCC are similar to those of other HPV-associated malignancies, with HPV oncogenes (E6 and E7) acting as key drivers of pathogenesis.

Treatment de-intensification is being pursued in clinical trials, although identifying the ~15% of patients with HPV⁺ OPSCC who have recurrent disease, and who therefore require more intensive treatment, remains a key challenge.

Evolution of a Paradigm Switch in Diagnosis and Treatment of HPV-Driven Head and Neck Cancer—Striking the Balance Between Toxicity and Cure

More than a decade after the discovery of p16 immunohistochemistry (IHC) as a surrogate for human papilloma virus (HPV)-driven head and neck squamous cell carcinoma (HNSCC), p16-IHC has become a routinely evaluated biomarker to stratify oropharyngeal squamous cell carcinoma (OPSCC) into a molecularly distinct subtype with favorable clinical prognosis. Clinical trials of treatment de-escalation frequently use combinations of biomarkers (p16-IHC, HPV-RNA in situ hybridization, and amplification of HPV-DNA by PCR) to further improve molecular stratification. Implementation of these methods into clinical routine may be limited in the case of RNA by the low RNA quality of formalin-fixed paraffin-embedded tissue blocks (FFPE) or in the case of DNA by cross contamination with HPV-DNA and false PCR amplification errors. Advanced technological developments such as investigation of tumor mutational landscape (NGS), liquid-biopsies (LBx and cell-free cfDNA), and other blood-based HPV immunity surrogates (antibodies in serum) may provide novel venues to further improve diagnostic uncertainties. Moreover, the value of HPV/p16-IHC outside the oropharynx in HNSCC patients needs to be clarified. With regards to therapy, postoperative (adjuvant) or definitive (primary) radiochemotherapy constitutes cornerstones for curative treatment of HNSCC. Side effects of chemotherapy such as bone-marrow suppression could lead to radiotherapy interruption and may compromise the therapy outcome. Therefore, reduction of chemotherapy or its replacement with targeted anticancer agents holds the promise to further optimize the toxicity profile of systemic treatment. Modern radiotherapy gradually adapts the dose. Higher doses are administered to the visible tumor bulk and positive lymph nodes, while a lower dose is prescribed to locoregional volumes empirically suspected to be invaded by tumor cells. Further attempts for radiotherapy de-escalation may improve acute toxicities, for example, the rates for dysphagia and feeding tube requirement, or ameliorate late toxicities like tissue scars (fibrosis) or dry mouth. The main objective of current de-intensification trials is therefore to reduce acute and/or late treatment-associated toxicity while preserving the favorable clinical outcomes. Deep molecular characterization of HPV-driven HNSCC and radiotherapy interactions with the tumor immune microenvironment may be instructive for the development of next-generation de-escalation strategies.

SUVmax for predicting regional control in oropharyngeal cancer

PURPOSE

To investigate the predictive value of pretherapeutic metabolic tumor imaging using 18-fluorodeoxyglucose positron emission tomography (FDG-PET) for regional response in oropharyngeal cancer patients undergoing primary (chemo)radiation.

METHODS

Retrospective analysis of oropharyngeal cancer patients treated with primary (chemo)radiation at the University Hospital Zurich from 2010 to 2019 with available FDG-PET. The SUV_max of the largest lymph node metastases was recorded. Regional response was assessed using posttherapeutic FDG-PET at 12 weeks and regional recurrence-free survival.

RESULTS

95 patients with a mean age of 68.5 years (SD 10.3) were included. The median pretherapeutic nodal SUV_max was 8.3 (interquartile range 4.4-13.3). A pretherapeutic nodal SUV_max above 6 significantly predicted poorer regional recurrence-free survival (log-rank test, P = 0.009) in univariate analysis. However, in multivariate analysis SUV_max above 6 was not significant in predicting regional recurrence-free survival (Cox regression P = 0.189). Clinical N category showed a trend in which a more severe stage had a poorer regional survival (Cox regression P = 0.073).

CONCLUSION

The SUV_max of the largest lymph node metastasis seems to play a role in predicting regional response in oropharyngeal cancer patients, after stratifying for N category. More research is needed to investigate whether highly metabolically active disease is less likely to respond to chemoradiation.

Radiomics outperforms clinical factors in characterizing human papilloma virus (HPV) for patients with oropharyngeal squamous cell carcinomas

Purpose:To utilize radiomic features extracted from CT images to characterize Human Papilloma Virus (HPV) for patients with oropharyngeal cancer squamous cell carcinoma (OPSCC).Methods:One hundred twenty-eight OPSCC patients with known HPV-status (60-HPV+ and 68-HPV-, confirmed by immunohistochemistry-P16-protein testing) were retrospectively studied. Radiomic features (11 feature-categories) were extracted in 3D from contrast-enhanced (CE)-CT images of gross-tumor-volumes using 'in-house' software ('ROdiomiX') developed and validated following the image-biomarker-standardization-initiative (IBSI) guidelines. Six clinical factors were investigated: Age-at-Diagnosis, Gender, Total-Charlson, Alcohol-Use, Smoking-History, and T-Stage. A Least-Absolute-Shrinkage-and-Selection-Operation (Lasso) technique combined with a Generalized-Linear-Model (Lasso-GLM) were applied to perform regularization in the radiomic and clinical feature spaces to identify the ranking of optimal feature subsets with most representative information for prediction of HPV. Lasso-GLM models/classifiers based on clinical factors only, radiomics only, and combined clinical and radiomics (ensemble/integrated) were constructed using random-permutation-sampling. Tests of significance (One-way ANOVA), average Area-Under-Receiver-Operating-Characteristic (AUC), and Positive and Negative Predictive values (PPV and NPV) were computed to estimate the generalization-error and prediction performance of the classifiers.Results:Five clinical factors, including T-stage, smoking status, and age, and 14 radiomic features, including tumor morphology, and intensity contrast were found to be statistically significant discriminators between HPV positive and negative cohorts. Performances for prediction of HPV for the 3 classifiers were: Radiomics-Lasso-GLM: AUC/PPV/NPV=0.789/0.755/0.805; Clinical-Lasso-GLM: 0.676/0.747/0.672, and Integrated/Ensemble-Lasso-GLM: 0.895/0.874/0.844. Results imply that the radiomics-based classifier enabled better characterization and performance prediction of HPV relative to clinical factors, and that the combination of both radiomics and clinical factors yields even higher accuracy characterization and predictive performance.Conclusion:Albeit subject to confirmation in a larger cohort, this pilot study presents encouraging results in support of the role of radiomic features towards characterization of HPV in patients with OPSCC.

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.

Low Frequency of Human Papillomavirus in Strictly Site-Coded Oral Squamous Cell Carcinomas, Using the Latest NHI/SEER-ICD Systems: A Pilot Observational Study and Critical Review

Simple Summary

The incidence of oropharyngeal squamous cell carcinomas (OPSCCs) has increased in the last decades, and this seems to be correlated to the infectious epidemiological trend of human papillomavirus (HPV). The prevalence of HPV-positive OPSCCs is approximately 70%, with involvement mainly of the tonsillar area. On the role of HPV in oral squamous cell carcinoma (OSCC), very few studies have investigated the prevalence of HPV in strictly site-codified OSCC, excluding the base of the tongue as distinct oropharyngeal entity. As a result, an inappropriate estimation of HPV infection in OSCC has been observed. We investigated HPV status, using a combination of detection methods, in a sample of 40 subjects with OSCC coded by the latest site classifications. Moreover, we performed a critical review of the studies with the same outcomes. The main finding of our investigation was a low frequency of HPV-positive OSCC, suggesting no significant HPV role in strictly oral carcinogenesis.

Abstract

The aim of this study was to evaluate HPV status in oral squamous cell carcinoma (OSCC), as coded by the latest classifications and applying a combination of detection methods used in clinical practice. Forty-two patients with suspect OSCC were consecutively recruited. Patients underwent an incisional biopsy for histological OSCC diagnosis and HPV identification by PCR DNA and p16 IHC. All lesions were coded by the latest ICD-0-3.2 site/histology classifications, as proposed for OSCC by the National Cancer Institute Surveillance, Epidemiology and End Results Programs. Moreover, a comparative analysis review, critically evaluated by the same site-coded systems and HPV detection methods, was performed. In 40 confirmed cases of OSCC, the frequency of HPV infection was 10% (4/40). Among positive patients, two cases were PCR DNA/p16 IHC positive (high-risk HPV 51, high-risk HPV 67), two cases were PCR DNA positive/p16 IHC negative (high-risk HPV 31 + 68, high-risk HPV 66). Applying the latest site coding systems for OSCC, the frequency of HPV infection in this study and in similar, reviewed investigations was low (from 3.3% to 12.5%). These results suggested no significant HPV role in oral carcinogenesis, particularly where an updated site-coded classification of OSCCs (categorically excluding the base of the tongue) had been performed.

Metachronous second primary neoplasia in oropharyngeal cancer patients: Impact of tumor HPV status. A GETTEC multicentric study

INTRODUCTION

Patients with oropharyngeal squamous cell carcinoma (OPSCC) display a significant risk to develop a metachronous second primary neoplasia (MSPN). HPV and non-HPV-related OPSCC are 2 distinct entities with biological, clinical and prognostic differences. The aims of our study were to analyze the impact of tumor HPV status and other relevant clinical factors, such as tobacco and/or alcohol (T/A) consumption, on the risk and distribution of MSPN in OPSCC patients and to assess the impact of MSPN on patient survival.

MATERIAL AND METHODS

All OPSCC patients treated from 2009 to 2014 were included in this multicentric retrospective study. P16 immunohistochemical expression was used as a surrogate maker of tumor HPV status. The impact of tumor p16 status on the risk of MSPN was assessed in uni- and multivariate analyses. Overall survival (OS) was determined by Kaplan-Meier analysis.

RESULTS

Among the 1291 patients included in this study, 138 (10.7%) displayed a MSPN which was preferentially located in the head and neck area (H&N), lung and esophagus. Multivariate analyses showed that p16- tumor status (p = 0.003), T/A consumption (p = 0.005) and soft palate tumor site (p = 0.009) were significantly associated with a higher risk of MSPN. We found no impact of p16 tumor status on the median time between index OPSCC diagnosis and MSPN development, but a higher proportion of MSPN arising outside the H&N, lung and esophagus was found in p16 + than in p16- patients. MSPN development had an unfavorable impact (p = 0.04) on OS only in the p16 + patient group.

CONCLUSION

P16 tumor status and T/A consumption were the main predictive factors of MSPN in OPSCC patients. This study provides crucial results with a view to tailoring global management and follow-up of OPSCC patients.

Diagnostic Accuracy of HPV Detection in Patients with Oropharyngeal Squamous Cell Carcinomas: A Systematic Review and Meta-Analysis

The aim of the study was to evaluate the diagnostic accuracy of Human Papillomavirus (HPV) techniques in oropharyngeal cancer. PubMed, EMBASE, the Cochrane Library and clinicaltrials.org were systematically searched for studies reporting methods of HPV detection. Primary outcomes were sensitivity and specificity of HPV detection. In this case, 27 studies were included (n = 5488, 41.6% HPV+). In this case, 13 studies evaluated HPV detection in tumour tissue, nine studies examined HPV detection in blood samples and five studies evaluated HPV detection in oral samples. Accuracy of HPV detection in tumour tissue was high for all detection methods, with pooled sensitivity ranging from 81.1% (95% CI 71.9-87.8) to 93.1% (95% CI 87.4-96.4) and specificity ranging from 81.1% (95% CI 71.9-87.8) to 94.9% (95% CI 79.1-98.9) depending on detection methods. Overall accuracy of HPV detection in blood samples revealed a sensitivity of 81.4% (95% CI 62.9-91.9) and a specificity of 94.8% (95% CI 91.4-96.9). In oral samples pooled sensitivity and specificity were lower (77.0% (95% CI 68.8-83.6) and 74.0% (95% CI 58.0-85.4)). In conclusion, we found an overall high accuracy for HPV detection in tumour tissue regardless of the HPV detection method used. HPV detection in blood samples may provide a promising new way of HPV detection.

A Contemporary Systematic Review on Repartition of HPV-Positivity in Oropharyngeal Cancer Worldwide

Significant variation in human papillomavirus (HPV) prevalence in oropharyngeal squamous cell carcinoma (OPSCC) across countries ranging from 11% in Brazil to 74% in New Zealand has been reported earlier. The aim of this study was to systematically review the most recently published studies on the occurrence of HPV in OPSCC globally. PubMed and Embase were systematically searched for articles assessing the occurrence of HPV+ OPSCC published between January 2016 and May 2021. Studies with a study period including 2015 and the following years were included. Both HPV DNA and/or p16 were accepted as indicators of HPV+ OPSCC. 31 studies were enrolled comprising 49,564 patients with OPSCC (range 12-42,024 patients per study) from 26 different countries covering all continents. The lowest occurrences of HPV+ OPSCC were observed in India (0%) and Spain (10%) and the highest occurrences were observed in Lebanon (85%) and Sweden (70%). We observed great variation in HPV prevalence in OPSCC worldwide varying from 0% to 85%. The highest occurrences of HPV+ OPSCC were found in general in Northern European countries, USA, Lebanon, China, and South Korea. We observed a trend of increase in HPV-positivity, indicating a mounting burden of HPV+ OPSCC.

Identification of High-Risk Human Papillomavirus DNA, p16, and E6/E7 Oncoproteins in Laryngeal and Hypopharyngeal Squamous Cell Carcinomas

Human papillomavirus (HPV) was proven to play a significant role in cancer development in the oropharynx. However, its role in the development of laryngeal (LSCC) and hypopharyngeal squamous cell carcinoma (HPSCC) remains to be clarified. High-risk HPV (HR-HPV) viral proteins E6 and E7 are considered to be pertinent to HPV-related carcinogenesis. Hence, our aim was to estimate LSCC and HPSCC for HR-HPV DNA, p16, and E6/E7 oncoprotein status by using molecular virology and immunohistochemistry methods. The prevalence of HPV16 infection was 22/41 (53.7%) and 20/31 (64.5%) for LSCC and HPSCC, accordingly. The majority of HPV16+ tumor samples were stage III or IV. In most samples, the presence of either HPV16 E6 or HPV16 E7 viral protein in dysplastic or tumor cells was confirmed using immunohistochemistry. Our results suggest a high prevalence of HPV16 as a primary HR-HPV type in LSCC and HPSCC. The lack of HPV E6/E7 oncoproteins in some tumor samples may suggest either the absence of viral integration or the presence of other mechanisms of tumorigenesis. The utilization of p16 IHC as a surrogate marker of HR-HPV infection is impractical in LSCC and HPSCC.

Discrepancy in p16 expression in patients with HPV-associated head and neck squamous cell carcinoma in Thailand: clinical characteristics and survival outcomes

BACKGROUND

Lower prevalence HPV infection has been previously reported in Thai population when compared with Western countries. p16 expression indicates HPV-associated oropharyngeal squamous cell carcinoma (OPSCC), but not non-OPSCC. We therefore evaluated the characteristic and association of p16 and HPV in Thai patients with HNSCC.

METHODS

We used immunohistochemistry and qPCR, respectively, to detect p16 and HPV DNA in archrival formalin-fixed paraffin-embedded HNSCC tissues. Patient characteristics and survival were analyzed.

RESULTS

p16 expression was detected in tumors of 72 of 662 (10.9%) patients with HNSCC and was significantly associated with higher-grade histology, advanced nodal stage, and oropharynx. p16 was expressed in 28 and 6.5% of patients with OPSCC or non-OPSCC, respectively, and HPV DNA was detected in 15.6 and 1% of patients, respectively. Using p16 as a surrogate for HPV status, sensitivities were 80 and 25% in OPSCC and non-OPSCC, respectively. Positive and negative predictive rates of OPSCC were 38 and 95%. Discordance rates between HPV and p16 were 23 and 7% in OPSCC and non-OPSCC, respectively. Overall survival (OS) were significantly longer in both p16-positive OPSCC (p = 0.049), and non-OPSCC (p = 0.003).

CONCLUSIONS

Low prevalence of p16 and HPV associated OPSCC and non-OPSCC were confirmed in Thai patients. High discordance and low positive predictive rates of p16 were observed in HPV-associated OPSCC. p16 was a significant prognostic factor for OS for patients with OPSCC or non-OPSCC. Therefore, HPV testing should be performed to assess the association of HPV with HNSCC regardless of p16 expression.

Oropharyngeal squamous cell carcinomas: Can imaging findings predict HPV status?

PURPOSE

This is first Australian population-based retrospective study in HPV-induced OPSCCs utilising CT. Contrast enhanced computed tomography (CECT) was utilised to assess if imaging findings of metastatic cystic lymph nodes (LNs) can predict human papillomavirus (HPV) status, as defined by p16 immunostaining of oropharyngeal squamous cell carcinomas (OPSCCs).

MATERIALS AND METHODS

The location and p16 status of primary tumours and LNs were recorded. Metastatic LNs were assessed for size, shape, margins and cystic changes. Hounsfield Units (HU) value of primary tumours and LNs were measured and tabulated. p16-positive and p16-negative groups were compared with respect to these variables. The two-sample t test and two-sample Mann-Whitney test was used.

RESULTS

A total of 364 CECT scans were reviewed with 209 patients (187 p16 positive and 22 p16 negative). Primary sites of OPSCCs were tonsils (58.8%), base of tongue (37.4%) and other oropharyngeal sites (3.8%). The HU values of p16-positive OPSCCs with mean of 78.6HU; 95% CI (76.5-80.8) were lower for p16-negative tumours, mean 96.0 HU CI 95% (85.5-106.6) for all oropharyngeal sub-sites. The mean HU values of p16-positive and p16-negative metastatic LNs were 38.8 HU 95% CI: (13-103 HU) versus 88.7 HU 95% CI: (54-131) (P < 0.0001).

CONCLUSIONS

The association between p16-positive status and the tonsillar cancer site is very high. Imaging features of p16-positive metastatic LNs include relatively large cystic neck nodes with low HU values. This is an imaging signature of p16-positive OPSCCs and can potentially influence patient's early diagnosis and prognosis.

Deep Learning Based HPV Status Prediction for Oropharyngeal Cancer Patients

Simple Summary

Determination of human papillomavirus (HPV) status for oropharyngeal cancer patients depicts a essential diagnostic factor and is important for treatment decisions. Current histological methods are invasive, time consuming and costly. We tested the ability of deep learning models for HPV status testing based on routinely acquired diagnostic CT images. A network trained for sports video clip classification was modified and then fine tuned for HPV status prediction. In this way, very basic information about image structures is induced into the model before training is started, while still allowing for exploitation of full 3D information in the CT images. Usage of this approach helps the network to cope with a small number of training examples and makes it more robust. For comparison, two other models were trained, one not relying on a pre-training task and another one pre-trained on 2D Data. The pre-trained video model preformed best.

Abstract

Infection with the human papillomavirus (HPV) has been identified as a major risk factor for oropharyngeal cancer (OPC). HPV-related OPCs have been shown to be more radiosensitive and to have a reduced risk for cancer related death. Hence, the histological determination of HPV status of cancer patients depicts an essential diagnostic factor. We investigated the ability of deep learning models for imaging based HPV status detection. To overcome the problem of small medical datasets, we used a transfer learning approach. A 3D convolutional network pre-trained on sports video clips was fine-tuned, such that full 3D information in the CT images could be exploited. The video pre-trained model was able to differentiate HPV-positive from HPV-negative cases, with an area under the receiver operating characteristic curve (AUC) of 0.81 for an external test set. In comparison to a 3D convolutional neural network (CNN) trained from scratch and a 2D architecture pre-trained on ImageNet, the video pre-trained model performed best. Deep learning models are capable of CT image-based HPV status determination. Video based pre-training has the ability to improve training for 3D medical data, but further studies are needed for verification.

Expression of p16, p53, and TLR9 in HPV-Associated Head and Neck Squamous Cell Carcinoma: Clinicopathological Correlations and Potential Prognostic Significance

Purpose

To investigate the association of human papillomavirus (HPV) status with p16, p53, and TLR9 expression in head and neck squamous cell carcinoma (HNSCC) and to evaluate these proteins as potential surrogate prognostic markers.

Methods

Expression of p16, p53, and TLR9 was assessed by immunohistochemistry, and HPV status was analyzed by in situ hybridization in 85 tumors of patients with HNSCC. Chi-square test was performed to evaluate the correlations of HPV infection with p16, p53, and TLR9 expression. Kaplan–Meier method and Cox regression analyses were applied to evaluate the associations between the expression levels of these proteins and patient outcomes.

Results

Overall, 24 of the 85 HNSCC specimens were associated with HPV infection. High expression of p16, p53, and TLR9 in tumor cells was observed in 31.76%, 61.18%, and 49.41% of the specimens, respectively. p16 showed a higher diagnostic odds ratio for the prediction of HPV DNA positivity than p53 and TLR9. Improved 5-year overall and disease-free survival correlated with HPV positivity and high p16, low p53, and low TLR9 expression. Associations with improved outcomes were also observed for marker combinations high p16/low p53 and high p16/low p53/low TLR9. In a multivariate analysis, the high p16/low p53 signature showed the lowest hazard ratio regarding death.

Conclusion

The expression of p16, p53, and TLR9 in HNSCC is associated with HPV status. High p53 and TLR9 expression may be related to poor outcomes. The two-marker signature high p16/low p53 in tumor cells is a reliable tool for patient survival prognostication in HNSCC.

In situ hybridization for high risk HPV E6/E7 mRNA in oropharyngeal squamous cell carcinoma

OBJECTIVES

To report a single institution's experience using human papillomavirus (HPV) E6/E7 mRNA in-situ hybridization (mRNA ISH) for HPV detection in oropharyngeal squamous cell carcinoma (OPSCC). To review the literature on HPV detection methods.

STUDY DESIGN

Retrospective chart review, literature review.

SETTING

Tertiary care academic hospital.

SUBJECTS AND METHODS

We conducted a retrospective chart review of 122 OPSCC biopsy specimens. mRNA ISH was performed on formalin-fixed paraffin-embedded (FFPE) tissue with a pool of 18 high risk HPV probes using an automated stainer; p16 immunohistochemistry (IHC) was also performed. We conducted a literature review on HPV detection methods including p16 IHC, mRNA ISH, DNA ISH, and PCR.

RESULTS

In our cohort, mRNA ISH had a sensitivity and specificity of 100% and 100% with reference to p16 (100% concordance). 2-year OS was 87.5% vs. 94.5% for p16/HPV-negative vs. positive patients. 2-year DFS was 60.0% vs. 84.2%. On literature review, mRNA ISH demonstrated consistently high sensitivity and specificity ranging from 88-98% and 90-100% respectively. In comparison, the specificity of p16 was 85-95%.

CONCLUSIONS

Our report supports the use of mRNA ISH for HPV detection in OPSCC and validates its feasibility using automated tissue staining methods on FFPE tissue. Our findings and literature review support that mRNA ISH may have superior specificity and be easier to interpret than p16. Further study on the prognostic value and cost-effectiveness of mRNA ISH is warranted and may establish this HPV detection method as the "gold standard."

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.

Detection of human papillomavirus in oropharyngeal squamous cell carcinoma

Worldwide there has been a significant increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC) etiologically attributed to oncogenic human papillomavirus (HPV). Reliable and accurate identification and detection tools are important as the incidence of HPV-related cancer is on the rise. Several HPV detection methods for OPSCC have been developed and each has its own advantages and disadvantages in regard to sensitivity, specificity, and technical difficulty. This review summarizes our current knowledge of molecular methods for detecting HPV in OPSCC, including HPV DNA/RNA polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), p16 immunohistochemistry (IHC), and DNA/RNA in situ hybridization (ISH) assays. This summary may facilitate the selection of a suitable method for detecting HPV infection, and therefore may help in the early diagnosis of HPV-related carcinoma to reduce its mortality, incidence, and morbidity.

Feasibility of Immunohistochemical p16 Staining in the Diagnosis of Human Papillomavirus Infection in Patients With Squamous Cell Carcinoma of the Head and Neck: A Systematic Review and Meta-Analysis

Human papillomavirus (HPV) is a risk factor for squamous cell carcinoma of the head and neck (HNSCC). This study aimed to investigate the feasibility of IHC- p16INK4a (p16) as an alternative modality for diagnosing HPV infection. We searched PubMed, EMBASE, Web of Science, and Cochrane library for studies that evaluated the diagnostic accuracy of IHC-p16 staining. A total of 30 studies involving 2,963 patients were included from 2007 to 2019. The combined sensitivity was 0.94 (95% CI: 0.92–0.95); specificity, 0.90 (95% CI: 0.89–0.91); positive likelihood ratio (LR), 6.80 (95% CI: 5.63–8.21); negative LR, 0.10 (95% CI: 0.07–0.16); diagnostic odds ratio, 85.98 (95% CI: 55.57–133.03); and area under the curve value, 0.9550. Subgroup analysis showed that the IHC-p16 test was more consistent with the in situ hybridization (ISH) test and has greater diagnostic value for oropharyngeal squamous cell carcinoma. The diagnostic efficacy of IHC-p16 varied among countries. In conclusion, IHC-p16 has high sensitivity and specificity for diagnosing HPV infection in HNSCC. The consistency of IHC-p16 findings with those of ISH indicate that their combination can be used to improve the specificity of diagnosis.

Predictive Value of HPV, p53, and p16 in the Post-Treatment Evolution of Malignant Tumors of the Oropharynx and Retromolar Trigone-Oropharynx Junction

Background and objectives: Knowledge of the interactions and influences of infectious, genetic, and environmental factors on the evolution and treatment response of malignant tumors is essential for improving the management of the disease and increasing patient survival. The objective of this study was to establish the contribution of human papillomavirus (HPV), as well as p53 and p16 tumor markers, alongside associated factors (smoking and alcohol consumption), in the progression of malignancies located in the oropharynx and at the retromolar trigone–oropharyngeal junction. Materials and Methods: We performed a prospective study including 50 patients with malignant tumors of the oropharynx and retromolar trigone–oropharyngeal junction. In all patients, the presence and type of HPV were determined, as well as the status of the tumor markers p53 and p16. The associated risk factors, biopsy results, treatment method, and post-treatment evolution were all documented. Statistical analyses were performed to evaluate the correlations between the determining factors and their influence on the post-treatment evolution. An overall increased survival rate was found in HPV(+) patients. Results: Our study outlined the prevalence of different high-risk subtypes of HPV from the ones presented by other studies, suggesting a possible geographic variation. Correlations between the p53 and p16 statuses and patient survival could be established. The association of smoking and alcohol consumption strongly correlated with an unfavorable evolution. Conclusions: Awareness of the differences in the post-treatment evolution of the patients in relation to the presence of the factors determined in our study could change the future management of such cases for ensuring improved treatment outcomes.

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.

Increasing prevalence of HPV in oropharyngeal carcinoma suggests adaptation of p16 screening in Southeast Asia

BACKGROUND

Human papillomavirus (HPV) is etiologically linked to increasing oropharyngeal squamous cell carcinoma (OPSCC) rates in the Western world. However, the role of HPV in Southeast Asia, a high incidence region, hasn't been assessed.

METHODS

96 formalin-fixed, paraffin-embedded (FFPE) tissue blocks and corresponding patient data were obtained from Srinagarind Hospital, Thailand from 2012-2017. DNA from areas of 70 %+ cellularity were genotyped using polymerase chain reaction (PCR) and stained for p16, a surrogate marker for HPV. Inverse probability weights based on data from the hospital-based cancer registry were used in statistical analyses. Adjusted linear regression was used to assess changes in OPSCC HPV prevalence and conduct projections. Kaplan-Meier and Cox proportional hazard models were used to determine HPV-specific survival differences.

RESULTS

14 patients exhibited monoinfection with HPV16, two with HPV18 and one was HPV16/18 coinfected. PCR results were in agreement with p16 staining. On average, HPV + patients were more likely to have tonsil cancer (p-value:0.002). HPV prevalence increased by 2% annually (pvalue: 0.01), from 16 % in 2012 to 26 % in 2017. At the current rate, OPSCC HPV positivity will exceed 50 % by 2030. HPV positivity was shown to be protective in Kaplan-Meier (log-rank p = 0.02) and sex, age and stage adjusted Cox models (HR:0.34 [95 %CI:0.22, 0.52]).

CONCLUSION

Given the increased prevalence and similarities in presentation of HPV + OPSCC to those observed in Western countries, the data suggest the adaptation of p16 staining and subsequent restaging of OPSCC tumors as suggested by the American Joint Committee on Cancer in Southeast Asia.

Diagnostic utility of high-risk human papillomavirus mRNA in situ hybridisation in squamous cell carcinoma of unknown primary in the head and neck and implementing American Society of Clinical Oncology guideline recommendations

INTRODUCTION

The American Society of Clinical Oncology (ASCO)-endorsed College of American Pathologists guideline recommends high-risk human papillomavirus (HPV) testing for metastatic squamous cell carcinoma (SCC) of lymph nodes level II/III of unknown primary. Herein, the performance of HPV-RNA in situ hybridisation (ISH) in detection of HPV-related SCC is evaluated implementing the ASCO guideline recommendations.

METHODS

Eighty head and neck (HN) SCC fine needle aspirations, which utilized HPV-RNA ISH/P16, were evaluated at Johns Hopkins Hospital (2015-2018) to investigate their performance and concordance with histology. The results were compared to a prior study of 59 HNSCCs, which HPV-DNA ISH.

RESULTS

Of the 80 reviewed fine needle aspirations, 65 (50 male, 15 female) were included. The mean age was 63.2 ± 14.0 years. The most common site was neck lymph nodes (47, 72.3%). Fifty-five cases (84.6%) were accompanied by concurrent core biopsy, and 48 cases (59.4%) had surgical follow-ups. HPV-RNA ISH was positive in 44 (67.7%), and P16 was strongly positive in 46 (70.8%). The HPV-RNA ISH/ P16 concordance rate was 92.3% on cytology material. The cytology/surgical concordance rate for HPV-RNA ISH was 88.9% (16/18). There was a discordance between the results in five cases (7.7%; HPV-RNA ISH-/P16+).

CONCLUSION

HPV-RNA ISH is a robust and reliable method for detecting HPV-related HNSCC on cytology material showing concordance rate of 92.3% between HPV-RNA ISH and P16, which is a sensitive but non-specific marker. Compared to HPV-DNA ISH, HPV-RNA ISH reproducibly identifies HPV-related HNSCC with fewer discrepancies between cytology and histology. The findings of this study are in agreement with the ASCO recommendations.

RNA in situ hybridization for human papillomavirus testing in oropharyngeal squamous cell carcinoma on a routine clinical diagnostic platform

BACKGROUND

The current diagnostic standard for detection of high-risk human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma is via a two-stage algorithm, namely p16 immunohistochemistry followed by HPV DNA in situ hybridization in p16 positive cases. This study evaluated the feasibility of automated RNA in situ hybridization on a clinical platform as a single-step alternative to the two-stage algorithm within a routine diagnostic histopathology setting.

METHODS

Thirty-eight cases positive for both p16 and DNA in situ hybridization, 42 p16 negative cases and 20 cases positive for p16 but negative for DNA in situ hybridization were randomly selected. High-risk HPV RNA in situ hybridization was undertaken on all cases on an automated clinical platform. Manufacturer-recommended and on-slide additional p16/HPV positive and negative controls were used. Test quality assurance and diagnostic RNA in situ hybridization were independently assessed by two observers. A consensus diagnosis was reached in the presence of a third observer on discordant cases. All RNA in situ hybridization results were then correlated against p16 and DNA ISH status.

RESULTS

Inter-slide RNA in situ hybridization staining variation was observed in control sections. RNA in situ hybridization demonstrated a high inter-observer agreement rate (κ = .897, P < .001). Following consensus review, there was full concordance between RNA in situ hybridization and the current standard.

CONCLUSION

Human papillomavirus testing by standalone automated RNA in situ hybridization on a clinical diagnostic platform currently available in routine diagnostic histopathology laboratories is a feasible alternative to the two-step algorithm of p16 and DNA in situ hybridization. Control tissue staining procedures need to be adapted to achieve the most accurate results.

Validation of local p16 testing for determination of human papilloma virus status eligibility on a low risk oropharyngeal cancer trial - A Trans-Tasman Radiation Oncology Group study

OBJECTIVE

Accurate determination of human papilloma virus (HPV) status is critical when identifying patients with oropharyngeal squamous cell carcinoma (OPSCC) who may be candidates for de-escalation trials. In this study we investigated whether local p16 screening, by immunohistochemistry (IHC), has high positive predictive value (PPV) for HPV status in a good prognosis HPV positive OPSCC (HPVOPSCC) population treated on a clinical trial.

METHODS AND MATERIALS

Patients enrolled on the TROG 12.01 randomised trial for good prognosis HPVOPSCC were randomised based on local p16 IHC testing but subsequently had central p16 IHC and HPV RNA in situ hybridisation (HPV RNA ISH) testing. Correlations between the local and central p16 and central HPV RNA ISH were studied. The main outcome was the positive predictive value (PPV) of local pathology laboratory testing of p16.

RESULTS

176/182 patients had samples available for central testing. 172/176 were evaluable for central testing of p16, and all were confirmed to be p16 positive (172/172, 100%, 95% CI = [97.9%, 100%]). Similarly, 100% of those evaluable for HPV RNA ISH (155/155, 100%, 95% CI = [97.6%, 100%]) were confirmed HPV positive, indicating p16 overexpression driven by transcriptionally active HPV and a PPV of 100% for local p16 testing.

CONCLUSIONS

Our results validate the suitability of local pathology laboratory p16 testing alone, in populations with a high attributable fraction of OPSCC due to HPV, to screen and enrol low risk HPVOPSCC patients onto de-intensification trials. This obviates the need for upfront more complex and expensive HPV assays and/or central laboratory testing.

Utility of p16 and HPV testing in oropharyngeal squamous cell carcinoma: An institutional review

In the US, 60% to 80% of oropharyngeal squamous cell carcinomas (OPSCCs) are associated with human papillomavirus (HPV). However, until recently, no consensus existed about when and how to test for HPV in patients with head and neck cancers. We aimed to evaluate the use of p16 and HPV testing at our institution because p16 immunohistochemistry is reportedly a reliable surrogate marker for HPV detection in OPSCCs.

METHODS

We identified all cases at our institution of primary or metastatic squamous cell carcinoma (SCC) of the head and neck with a concurrent p16 immunostain analysis from January 1, 2013, through August 31, 2018. Patient demographic data, tumor characteristics, p16 result, and any HPV result (in situ hybridization and E6 and E7 RNA test) were captured.

RESULTS

We identified 104 patients. Most primary tumors (53/57 [93.0%]) and metastases (40/47 [85.1%]) were positive for p16. Thirty-seven cases (35.6%) had reflex high-risk HPV (HR HPV) testing performed. Of the 35 p16-positive cases, 6 had discrepant HR HPV results (p16⁺ /HPV^- ). We identified 47 p16 immunostains that were performed on lymph nodes with primary tumors of unknown origin. Most were cytology cases (34/47 [72.3%]), and most were p16 positive (40/47 [85.1%]). Neither tumor differentiation nor tumor keratinization was predictive of p16 positivity. Tumors with basaloid differentiation were universally p16 positive.

CONCLUSION

p16 immunohistochemistry accurately identifies HPV-positive OPSCC. Cytology specimens have an important role in characterizing SCC of unknown origin. HR HPV testing is not routinely required, and results may be discrepant with p16 findings.