Ancillary studies in determining human papillomavirus status of squamous cell carcinoma of the oropharynx: a review

Biomarkers in head and neck squamous cell carcinoma: unraveling the path to precision immunotherapy

Recent strides in understanding the molecular underpinnings of head and neck cancers have sparked considerable interest in identifying precise biomarkers that can enhance prognostication and enable personalized treatment strategies. Immunotherapy has particularly revolutionized the therapeutic landscape for head and neck squamous cell carcinoma, offering new avenues for treatment. This review comprehensively examines the application and limitations of the established and emerging/novel biomarkers for head and neck squamous cell carcinoma. Established biomarkers, including well-characterized genetic mutations, protein expressions, and clinical factors, have been extensively studied and validated in clinical practice. Novel biomarkers identified through molecular analyses, including novel genetic alterations, immune-related markers, and molecular signatures, are currently being investigated and validated in preclinical and clinical settings. Biomarkers hold the potential to deepen our understanding of head and neck squamous cell carcinoma biology and guide therapeutic strategies. The evolving paradigm of predictive biomarkers facilitates the study of individual responses to specific treatments, including targeted therapy and immunotherapy.

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.

NCCN Guidelines® Insights: Head and Neck Cancers, Version 1.2022

The NCCN Guidelines for Head and Neck Cancers address tumors arising in the oral cavity (including mucosal lip), pharynx, larynx, and paranasal sinuses. Occult primary cancer, salivary gland cancer, and mucosal melanoma (MM) are also addressed. The specific site of disease, stage, and pathologic findings guide treatment (eg, the appropriate surgical procedure, radiation targets, dose and fractionation of radiation, indications for systemic therapy). The NCCN Head and Neck Cancers Panel meets at least annually to review comments from reviewers within their institutions, examine relevant new data from publications and abstracts, and reevaluate and update their recommendations. These NCCN Guidelines Insights summarize the panel's most recent recommendations regarding management of HPV-positive oropharynx cancer and ongoing research in this area.

Cancer of the Oropharynx and the Association with Human Papillomavirus

Squamous cell carcinoma of the oropharynx (OPC) consists of human papillomavirus (HPV)-negative disease caused by tobacco and alcohol use, and HPV-positive disease caused by the sexually transmitted infection HPV. These entities have unique but overlapping risk factors, epidemiologic trends, staging systems, and survival outcomes. HPV-positive tumor status confers a significant survival benefit compared with HPV-negative disease. OPC treatment entails a combination of surgery, radiation, and chemotherapy. Ongoing trials will determine whether treatment of HPV-related disease may be safely deintensified to decrease morbidity. Emerging HPV-related biomarkers are under study as tools to inform screening, diagnosis, treatment, and surveillance for HPV-positive OPC.

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.

Oropharyngeal squamous cell carcinoma: radiomic machine-learning classifiers from multiparametric MR images for determination of HPV infection status

We investigated the ability of machine-learning classifiers on radiomics from pre-treatment multiparametric magnetic resonance imaging (MRI) to accurately predict human papillomavirus (HPV) status in patients with oropharyngeal squamous cell carcinoma (OPSCC). This retrospective study collected data of 60 patients (48 HPV-positive and 12 HPV-negative) with newly diagnosed histopathologically proved OPSCC, who underwent head and neck MRIs consisting of axial T1WI, T2WI, CE-T1WI, and apparent diffusion coefficient (ADC) maps from diffusion-weighted imaging (DWI). The median age was 59 years (the range being 35 to 85 years), and 83.3% of patients were male. The imaging data were randomised into a training set (32 HPV-positive and 8 HPV-negative OPSCC) and a test set (16 HPV-positive and 4 HPV-negative OPSCC) in each fold. 1618 quantitative features were extracted from manually delineated regions-of-interest of primary tumour and one definite lymph node in each sequence. After feature selection by using the least absolute shrinkage and selection operator (LASSO), three different machine-learning classifiers (logistic regression, random forest, and XG boost) were trained and compared in the setting of various combinations between four sequences. The highest diagnostic accuracies were achieved when using all sequences, and the difference was significant only when the combination did not include the ADC map. Using all sequences, logistic regression and the random forest classifier yielded higher accuracy compared with the that of the XG boost classifier, with mean area under curve (AUC) values of 0.77, 0.76, and 0.71, respectively. The machine-learning classifier of non-invasive and quantitative radiomics signature could guide the classification of the HPV status.

Inflammatory markers as prognostic factors of recurrence in advanced-stage squamous cell carcinoma of the head and neck

Background

Multiple immunologic parameters have provided useful prognostic and assessment significance in various cancers, including head-and-neck squamous cell carcinoma (scc). We sought to identify whether pretreatment inflammatory markers could prognosticate recurrence in patients with advanced (stage iii or iv) head-and-neck scc who underwent therapy with curative intent in a tertiary care centre between January 2010 and December 2012.

Methods

In a chart review, we recorded demographics; primary tumour characteristics; p16 status; pretreatment inflammatory markers, including body mass index (bmi), neutrophil-to-lymphocyte ratio (nlr), C-reactive protein (crp), and serum albumin; therapy received; and date of relapse, death, or last follow-up. The main outcome was relapse-free survival (rfs). Overall survival (os) was a secondary outcome.

Results

From among 235 charts reviewed, 118 cases were included: 86 oropharyngeal (50 p16-positive, 18 p16-negative, 17 p16 unavailable, 1 p16 indeterminate), and 32 non-oropharyngeal (7 p16-positive, 19 p16-negative, 6 p16 unavailable). Median follow-up was 2.45 years (25%-75% interquartile range: 1.65-3.3 years). In univariate analysis, p16 status, bmi, modified Glasgow prognostic score, and crp were significant for rfs, but in multivariate analysis, only p16 status, bmi, and crp remained significant. For os, only crp and nlr were significant in both the univariate and multivariate analyses. After adjustment for p16 status, nlr did not remain significant. After adjustment for p16 status, crp remained significant for both rfs and os.

Conclusions

In patients with head-and-neck scc, a stronger prognostic value is associated with human papillomavirus status than with nlr and many other factors, including bmi and albumin. However, even though few of our patients had high crp, serum crp remained significant despite p16-positive status.

Molecular mechanisms underlying increased radiosensitivity in human papillomavirus-associated oropharyngeal squamous cell carcinoma

Oropharyngeal squamous cell carcinoma (OPSCC) is an important type of head and neck squamous cell carcinoma (HNSCC). The traditional risk factors for OPSCC include carcinogen intake, smoking, alcohol consumption, and lifestyle. In recent years, cases of human papillomavirus (HPV)-related OPSCC have gradually increased. At present, HPV-related OPSCC in developed Western countries comprise up to 90% of all OPSCC cases, while in other developing countries, the proportion of HPV-related OPSCC cases is also gradually increasing. Compared with HPV-negative OPSCC, HPV-positive OPSCC patients have better overall survival rates and local control rates and this improved prognosis may be related to the increased radiosensitivity of HPV-positive tumors. Due to this more favorable prognosis, many downgraded treatment schemes are gradually emerging, including simple radiotherapy instead of concurrent radiotherapy or reduced radiotherapy dose. However, there is insufficient theoretical basis for such schemes. Some studies have shown that delayed repair of DNA damage after radiation, G2/M arrest, increased hypoxia, and decreased proliferation capacity are the main reasons for the increased radiosensitivity of HPV-positive tumor cells. In this review, we discuss the four principles of tumor cell damage caused by radiation, including repair, reoxygenation, redistribution, and regeneration in order to reveal the mechanism whereby HPV increases the radiosensitivity of tumor cells. An attempt was made to provide sufficient information to facilitate more individualized treatment for HPV-positive OPSCC patients, under the premise of good tumor control.

Role of human papillomavirus in laryngeal squamous cell carcinoma: A meta-analysis of cohort study

Objective

To evaluate the association of human papilloma virus (HPV) infection with prognosis, specifically overall survival (OS) and disease‐free survival (DFS), in laryngeal squamous cell carcinoma (LSCC) patients.

Method

A systematic review and meta‐analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. LSCC was confirmed on the basis of histopathology, whereas HPV status was confirmed by polymerase chain reaction.

Results

A total of 6539 articles were initially searched from 8 databases, of which 11 studies were eligible for our review. A total of 1442 LSCC cases were included in this analysis. Eight studies examined 3‐year OS for LSCC. The pooled hazard ratio (HR) from the 8 studies was 0.29 (95% CI: 0.25‐0.33). There was a statistically significant difference in 3‐year OS between the HPV‐negative and ‐positive groups, with the latter having a better survival. There was no statistically significant differences in 5‐ and 10‐year OS. Five studies examined 3‐ and 5‐year DFS for LSCC, whereas only 3 studies examined 10‐year DFS. There was no statistically significant difference in 3‐, 5‐, and 10‐year DFS between the HPV groups.

Conclusion

This study evaluated the survival impact of HPV infection in LSCC patients. The OS of the HPV‐positive group was better than that of the HPV‐negative group in terms of short‐term survival. Compared with the HPV‐negative group, the HPV‐positive group had a better trend of DFS, suggesting that a larger sample size and further exploration of the pathology and local control of HPV‐positive tumors are needed.

Frequency of HPV in oral cavity squamous cell carcinoma

BACKGROUND

The prevalence of high-risk human papillomavirus (HPV) DNA in cases of oral cavity squamous cell carcinoma (SCC) varies widely. The aim of this study is to investigate the frequency of high-risk HPV DNA in a large Brazilian cohort of patients with oral cavity SCC.

METHODS

Biopsy and resected frozen and formalin-fixed paraffin-embedded specimens of oral cavity SCC were available from 101 patients who were recruited at two Brazilian centres. Stringent measures with respect to case selection and prevention of sample contamination were adopted to ensure reliability of the data. Nested PCR using MY09/MY11 and GP5⁺/GP6⁺ as well as PGMY09/11 L1 consensus primers were performed to investigate the presence of HPV DNA in the tumours. HPV-positive cases were subjected to direct sequencing. Shapiro-Wilk and Student t test were used to evaluate data normality and to compare the means, respectively. Qualitative variables were analysed by logistic regression.

RESULTS

Our results demonstrate that the frequency of high-risk HPV types in oral cavity SCC is very low and is less than 4%. All HPV-positive cases were HPV16. In addition, our results do not show a significant association between the tumour clinical features and the risk factors (tobacco, alcohol and HPV) for oral cavity SCC.

CONCLUSION

In the current study, we observed an overlapping pattern of risk factors that are related to tumour development. This, along with a low frequency of high-risk HPV DNA, supports the findings that HPV is not involved in the genesis of oral cavity SCC in Brazilian population.

Risk of second primary cancer after a first potentially-human papillomavirus-related cancer: A population-based study

Human papillomaviruses (HPV) are involved in the development of anogenital and head and neck cancers. The purpose of this study was to assess the risk of developing a second primary cancer (SPC) after a first potentially-HPV-related cancer, and to analyze the sites where SPCs most frequently occurred in these patients. All patients with a first cancer diagnosed between 1989 and 2004, as recorded by 10 French cancer registries, were followed up until December 31, 2007. Only invasive potentially-HPV-related cancers (namely, cervical, vagina, vulva, anal canal, penile, oropharynx, tongue and tonsil) were included. Standardized Incidence Ratios (SIRs) were calculated to assess the risk of SPC. A multivariate Poisson regression model was used to model SIRs separately by gender, adjusted for the characteristics of the first cancer. 10,127 patients presented a first potentially-HPV-related cancer. The overall SIR was 2.48 (95% CI, 2.34-2.63). The SIR was 3.59 (95% CI, 3.33-3.86) and 1.61 (95% CI, 1.46-1.78) in men and women respectively. The relative risk of potentially-HPV-related SPC was high among these patients (SIR=13.74; 95% CI, 8.80-20.45 and 6.78; 95% CI, 4.61-9.63 for men and women, respectively). Women diagnosed in the most recent period (2000-2004) showed a 40% increase of their relative risk of SPC as compared with women diagnosed between 1989 and 1994 (ratio of SIRs=1.40; 95% CI, 1.06-1.85). HPV cancer survivors face an increased risk of SPC, especially second cancer. Clinicians may consider this increased risk of developing HPV-related SPC during follow-up to improve subsequent cancer prevention in these patients.

HPV Infection, but Not EBV or HHV-8 Infection, Is Associated with Salivary Gland Tumours

Benign and malignant salivary gland tumours are clinically heterogeneous and show different histology. Little is known about the role of human herpes virus 8 (HHV-8), Epstein-Barr virus (EBV), and human papillomavirus (HPV) infection in salivary gland neoplasms. We investigated the presence of the three viruses in formalin-fixed, paraffin-embedded tissue samples in a cohort of 200 different salivary gland tumours. We performed EBV-LMP-1 and HHV-8 and p16 immunohistochemistry, a specific chip based hybridization assay for detection and typing of HPV and a chromogenic in situ hybridization for EBV analysis. Only one case, a polymorphic low-grade carcinoma, showed HHV-8 expression and one lymphoepithelial carcinoma was infected by EBV. In 17 cases (9%) moderate or strong nuclear and cytoplasmic p16 expression was detected. The HPV type was investigated in all of these cases and additionally in 8 Warthin's tumours. In 19 cases HPV type 16 was detected, mostly in Warthin's tumour, adenoid cystic carcinoma, and adenocarcinoma NOS. We concluded that HHV-8 infection and EBV infection are not associated with salivary gland cancer, but HPV infection may play a role in these tumour entities.

Immune therapy for human papillomaviruses-related cancers

Human papillomaviruses (HPVs) are a large family of double strand DNA viruses comprising more than 180 types. Infection with HPV is very common and it is associated with benign and malignant proliferation of skin and squamous mucosae. Many HPVs, considered low-risk such as HPV 6 and 11, produce warts; while high-risk viruses, such as HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, and 58, induce tumors. About 5% of all cancers in men and women are associated with HPV infection. Because there are not antiviral drugs for HPV infection, current therapies for low-risk HPV infections involve physical removal of the lesion by cryotherapy, trichloracetic acid, laser, or surgical removal. Surgical procedures are effective in the treatment of pre-cancerous lesions, however after these procedures, many recurrences appear due to new re-infections, or to failure of the procedure to eliminate the HPV. In addition, HPV can inhibit recognition of malignant cells by the immune system, leading to the development of cancer lesions. When this occurs, radiotherapy and chemotherapy are then used. Unfortunately, about 50% of the HPV-cancer patients still die. In the past decade, a better knowledge of the natural history of the virus-host interaction and of the immune response against this viral infection has brought new therapeutic strategies geared to modulate the immune system to generate an efficient virus-specific cytotoxic response. Novel HPV protein-expressing vaccines have shown some significant clinical efficacy and systemic HPV-specific cytotoxic T cell responses. This review will describe the current status of the several therapeutic strategies used to treat HPV-induced lesions, and discuss the various new therapies now being tested.

Correlation of EGFR, pEGFR and p16INK4 expressions and high risk HPV infection in HIV/AIDS-related squamous cell carcinoma of conjunctiva

Background

Squamous cell carcinoma of conjunctiva has increased tenfold in the era of HIV/AIDS. The disease pattern has also changed in Africa, affecting young persons, with peak age-specific incidence of 30-39 years, similar to that of Kaposi sarcoma, a well known HIV/AIDS defining neoplasm. In addition, the disease has assumed more aggressive clinical course. The contributing role of exposure to high risk HPV in the development of SCCC is still emerging.

Objective

The present study aimed to investigate if immunohistochemical expressions of EGFR, pEGFR and p16, could predict infection with high risk HPV in HIV-related SCCC.

Methods

FFPE tissue blocks of fifty-eight cases diagnosed on hematoxylin and eosin with SCCC between 2005-2011, and subsequently confirmed from medical records to be HIV positive at the department of human pathology, UoN/KNH, were used for the study. Immunohistochemistry was performed to assess the expressions of p16INK4A, EGFR and pEGFR. This was followed with semi-nested PCR based detection and sequencing of HPV genotypes. The sequences were compared with the GenBank database, and data analyzed for significant statistical correlations using SPSS 16.0. Ethical approval to conduct the study was obtained from KNH-ERC.

Results

Out of the fifty-eight cases of SCCC analyzed, twenty-nine (50%) had well differentiated (grade 1), twenty one (36.2%) moderately differentiated (grade 2) while eight (13.8%) had poorly differentiated (grade 3) tumours. Immunohistochemistry assay was done in all the fifty eight studied cases, of which thirty nine cases (67.2%) were positive for p16INK4A staining, forty eight cases (82.8%) for EGFR and fifty one cases (87.9%) showed positivity for p-EGFR. HPV DNA was detected in 4 out of 40 SCCC cases (10%) in which PCR was performed, with HPV16 being the only HPV sub-type detected. Significant statistical association was found between HPV detection and p16INK4 (p=0.000, at 99% C.I) and EGFR (p=0.028, at 95% C.I) expressions, but not pEGFR. In addition, the expressions of these biomarkers did not show any significant association with tumor grades.

Conclusion

This study points to an association of high risk HPV with over expressions of p16INK4A and EGFR proteins in AIDS-associated SCCC.

HPV Prevalence and Prognostic Value in a Prospective Cohort of 255 Patients with Locally Advanced HNSCC: A Single-Centre Experience

Background. HPV is a positive prognostic factor in HNSCC. We studied the prevalence and prognostic impact of HPV on survival parameters and treatment toxicity in patients with locally advanced HNSCC treated with concomitant chemoradiation therapy. Methods. Data on efficacy and toxicity were available for 560 patients. HPV was detected by PCR. Analysis was performed using Kaplan-Meier survival curves, Fisher's test for categorical data, and log-rank statistics for failure times. Results. Median follow-up was 4.7 years. DNA extraction was successful in 255 cases. HPV prevalence was 68.6%, and 53.3% for HPV 16. For HPV+ and HPV−, median LRC was 8.9 and 2.2 years (P = 0.0002), median DFS was 8.9 and 2.1 years (P = 0.0014), and median OS was 8.9 and 3.1 years (P = 0.0002). Survival was different based on HPV genotype, stage, treatment period, and chemotherapy regimen. COX adjusted analysis for T, N, age, and treatment remained significant (P = 0.004). Conclusions. Oropharyngeal cancer is increasingly linked to HPV. This study confirms that HPV status is associated with improved prognosis among H&N cancer patients receiving CRT and should be a stratification factor for clinical trials including H&N cases. Toxicity of CRT is not modified for the HPV population.

Tumor cell anaplasia and multinucleation are predictors of disease recurrence in oropharyngeal squamous cell carcinoma, including among just the human papillomavirus-related cancers

Oropharyngeal squamous cell carcinoma (SCC) is frequently related to high risk human papillomavirus. This tumor expresses p16, frequently has a nonkeratinizing morphology, and has improved outcomes. Despite having a good prognosis, tumors can have focal or diffuse nuclear anaplasia or multinucleation, the significance of which is unknown. From a database of 270 oropharyngeal SCCs with known histologic typing (using our established system) and p16 immunohistochemistry, all surgically resected cases (149) were reviewed. Anaplasia was defined as any × 40 field with ≥ 3 tumor nuclei with diameters ≥ 5 lymphocyte nuclei (~25 μm), and multinucleation was defined as any × 40 field with ≥ 3 tumor cells with multiple nuclei. p16 was positive in 128 cases (85.9%), 64 cases (43.0%) showed anaplasia, and 71 (47.7%) showed multinucleation. Anaplasia and multinucleation were highly related (P<0.001), and both also correlated with histologic type (P<0.001 and P=0.01, respectively), p16 status (P=0.09 and 0.03, respectively), and partially with nodal extracapsular extension. There was no correlation with any of the other variables. In univariate analysis, cases showing anaplasia or multinucleation had worse overall, disease-specific, and disease-free survival (P<0.006 for all). Higher T-stage, keratinizing histologic type, extracapsular extension, and smoking also all correlated with worse survival. In multivariate analysis, anaplasia and multinucleation both predicted worse disease-specific survival (hazard ratio 9.9, P=0.04; and hazard ratio 11.9, P=0.02, respectively) independent of the other variables. In summary, among surgically resectable oropharyngeal SCC (including among just the p16-positive cohort), tumor cell anaplasia and multinucleation independently correlated with disease recurrence and poorer survival.

Validation of methods for oropharyngeal cancer HPV status determination in US cooperative group trials

Tumor human papillomavirus (HPV) status is a prognostic factor for oropharyngeal cancer, but classification methods are not standardized. Here we validate the HPV classification methods used in US cooperative group trials. Tumor DNA and RNA purified from 240 paraffin-embedded oropharyngeal cancers diagnosed from 2000 to 2009 were scored as evaluable if positive for DNA and mRNA controls by quantitative polymerase chain reaction (PCR). Eighteen high-risk (HR) HPV types were detected in tumors by consensus PCR, followed by HR-HPV E6/7 oncogene expression analysis by quantitative reverse transcriptase PCR. The sensitivity (S), specificity (SP), and positive (PPV) and negative predictive values (NPV) of p16 expression detected by immunohistochemistry (IHC) and HPV16 detected by in situ hybridization (ISH) were evaluated in comparison with HR-HPV E6/7 oncogene expression. Interrater agreement among 3 pathologists was evaluated by κ statistics. Of 235 evaluable tumors, 158 (67%; 95% confidence interval, 61.2-73.3) were positive for HR-HPV E6/7 oncogene expression [HPV type 16 (92%), 18 (3%), 33 (3%), 35 (1%), or 58 (1%)]. p16 IHC had high sensitivity (S 96.8%, SP 83.8%, PPV 92.7%, and NPV 92.5%), whereas HPV16 ISH had high specificity (S 88.0%, SP 94.7%, PPV 97.2%, and NPV 78.9%) for HR-HPV oncogene expression. Interrater agreement was excellent for p16 (κ=0.95 to 0.98) and HPV16 ISH (κ=0.83 to 0.91). Receiver operating curve analysis determined the cross-product of p16 intensity score and percentage of tumor staining to optimally discriminate HR-HPV E6/7-positive and HR-HPV E6/7-negative tumors. p16 IHC and HPV16 ISH assays show excellent performance, with high sensitivity and specificity, respectively. A new validated H-score for p16 IHC assessment is proposed. Appropriate assay choice depends on clinical implications of a false-positive or false-negative test.