Prognostic significance of human papillomavirus 16 viral load level in patients with oropharyngeal cancer

Prognostic impact of intra tumoral HPV-16 viral load in oropharyngeal squamous cell carcinomas

OBJECTIVES

The incidence of HPV-induced oropharyngeal squamous cell carcinoma (OSCC) is constantly increasing. Although HPV-related OSCC carry a better prognosis, the majority of patients with an HPV-positive OSCC have other prognostic factors such as tobacco smoking, making therapeutic de-escalating approaches less precise. In this context, our study aims to evaluate the prognostic impact of intra-tumoral HPV-16 viral load (VL) in OSCC.

MATERIAL AND METHODS

We conducted a retrospective analysis of p16-positive OSCC samples from patients treated between 2012 and 2019. Viral load (VL) was determined using digital droplet Polymerase Chain Reaction (ddPCR) and described according to 3 subgroups: low (<0.9 copies/cell), medium (0.9-85 copies/cell), and high (>85 copies/cell). We assessed the correlation between VL and recurrence-free survival (RFS), specific survival (SS), and overall survival (OS) using the Kaplan-Meier method.

RESULTS

In total, 192 patients were included; 148 (77 %) were male. The mean age was 65. HPV-16 was detected in 189/192 samples (98 %). T3-4-stage (p = 0.002), metastasis (p = 0.007), and tobacco consumption (p = 0.01) predicted lower OS. High VL was associated with higher RFS (HR = 0.2, p = 0.01), SS (HR = 0.32, p = 0.02), and OS (HR = 0.39, p = 0.03). After adjusting for tobacco consumption and tumor stage, high VL remained associated with higher RFS (HR = 0.1, 95 %CI [0.04-0.7], p = 0.01) and SS (HR = 0.20, 95 %CI [0.05-0.75], p = 0.01).

CONCLUSION

In our study, high intra-tumoral HPV VL was independently associated with survival. Subject to further validation in independent and prospective cohorts, our findings suggest that HPV VL could help to refine the prognosis of HPV positive OSCC patients.

Human papillomavirus-driven head and neck cancers in Japan during 2008-2009 and 2018-2019: The BROADEN study

There is limited understanding of epidemiology and time trends of human papilloma virus (HPV)-driven head and neck cancers (HNC) in Japan, especially outside of the oropharynx. To assess HPV-driven HNC, a non-interventional study (BROADEN) of HNC patients diagnosed in 2008-2009 and 2018-2019 was conducted in Japan. Adult patients with oropharyngeal, nasopharyngeal, laryngeal, hypopharyngeal or oral cavity cancers were included in this study. HPV was centrally tested using p16INK4a immunohistochemistry, HPV-DNA PCR and HPV E6*I mRNA. HPV attributability required positivity in at least two tests (p16INK4a immunohistochemistry, HPV-DNA PCR, HPV E6*I mRNA) in the oropharynx, and HPV-DNA and HPV E6*I mRNA positivity for non-oropharynx sites. Nineteen hospitals included a total of 1108 patients, of whom 981 had valid samples. Men accounted for 82% of HNC diagnoses. Patients in the earlier cohort were younger and included a higher percentage of smokers. There was an increasing trend of HPV-driven oropharyngeal cancer over the last decade, from 44.2% to 51.7%. HPV attribution in nasopharyngeal cancers was 3.2% in 2008-2009 and 7.5% in 2018-2019; and 4.4% and 0% for larynx respectively. In total, 95.2% of HPV-driven HNC were attributed to HPV genotypes included in the 9-valent HPV vaccine being HPV16 the most prominent genotype. These results suggest that an epidemiologic shift is happening in Japan, with a decrease in smoking and alcohol use and an increase in HPV-driven HNC. The increasing trend of HPV-driven HNC in Japan highlights the need for preventive strategies to mitigate the rise of HPV-driven HNC.

Human papillomavirus (HPV) load is higher in HPVDNA/p16 positive than in HPVDNA positive/p16 negative oropharyngeal squamous cell carcinoma but does not differ significantly between various subsites or correlate to survival

OBJECTIVE

Patients with human papillomavirus DNA positive (HPVDNA+) and p16ink4a overexpressing (p16+) oropharyngeal squamous cell carcinoma (OPSCC), especially those with cancer in the tonsillar and base of tongue subsites as compared to other OPSCC subsites have a better outcome than those with only HPVDNA+ or only p16+ cancer. Likewise having a high viral load has been suggested to be a positive prognostic factor. We therefore hypothesized, that HPV viral load could vary depending on OPSCC subsite, as well as with regard to whether the cancer was HPVDNA+ and p16+, or only HPVDNA+, or only p16+ and that this affected outcome.

MATERIAL AND METHODS

To address these issues HPV viral load was determined by HPV digital droplet (dd) PCR in tumor biopsies with previously known HPVDNA/p16 status from 270 OPSCC patients diagnosed 2000-2016 in Stockholm, Sweden. More specifically, of these patients 235 had HPVDNA+/p16+, 10 had HPVDNA+/p16-, 13 had HPVDNA-/p16+ and 12 had HPVDNA-/p16- cancer.

RESULTS

We found that HPVDNA+/p16+ OPSCC had a significantly higher viral load than HPVDNA+/p16- OPSCC. Moreover, there was a tendency for a higher viral load in the tonsillar and base of tongue OPSCC subsites compared to the other subsites and for a low viral load to correlate to a better clinical outcome but none of these tendencies reached statistical significance.

CONCLUSION

To conclude, the mean viral load in HPVDNA+/p16+ OPSCC was higher than in HPVDNA+/p16- OPSCC, but there was no statistically significant difference in viral load depending on OPSCC subsite or on clinical outcome.

Pretreatment Circulating HPV16 DNA Viral Load Predicts Risk of Distant Metastasis in Patients with HPV16-Positive Oropharyngeal Cancer

BACKGROUND

There are definite reasons to implement molecular diagnostics based on the measurement of human papillomavirus (HPV) DNA in liquid biopsy into clinical practice. It is a quick, repeatable, and health-safe test for cancer biomarkers in the blood. In this study, we investigated whether the circulating tumor-related HPV16 (ctHPV16) viral load (VL) in patients with oropharyngeal squamous cell carcinoma (OPSCC) was important for determining the risk of locoregional recurrence-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS).

METHODS

This study included 91 patients with ctHPV16-positive OPSCC who had been treated with radical radiotherapy and chemotherapy. The VL was measured using quantitative PCR (qPCR) and a probe specific for HPV16. Based on 10 years of follow-up, the 2-, 3-, 5-, and 9-year LRFS, MFS, and OS were estimated.

RESULTS

The 5-year actuarial LRFS, MFS, and OS rates of patients with ctHPV16-positive/OPSCC were 88%, 90%, and 81%, respectively. The VL was significantly higher in patients who subsequently developed distant metastases (DM) than in those who did not (VL 4.09 vs. 3.25; p = 0.009). In a Cox proportional hazards regression model for MFS, a higher ctHPV16 VL appeared to be a significant independent prognostic factor for the occurrence of DM (HR 2.22, p = 0.015). The ROC curve revealed a cutoff value of 3.556 for VL (p = 0.00001).

CONCLUSIONS

A high VL before treatment indicates patients with a significant risk of DM, and should be used in OPSCC treatment stratification.

Determinants of the level of circulating-tumor HPV16 DNA in patients with HPV-associated oropharyngeal cancer at the time of diagnosis

Circulating tumor HPV DNA (ctHPV16) assessed in liquid biopsy may be used as a marker of cancer in patients with HPV-associated oropharyngeal cancer (HPV + OPC). Factors influencing the initial ctHPV16 quantity are not well recognized. In this study we aimed to establish what factors are related to the level of ctHPV16 at the time of diagnosis. 51 patients (37 men and 14 women, median age of 57 years old) with HPV + OPC prior to definitive treatment were included. ctHPV16 was measured by qPCR. Tumor and nodal staging were assessed according to AJCC8. Blood derived factors included squamous cell carcinoma antigen (SCC-Ag), serum soluble fragment of cytokeratin 19 (CYFRA 21-1), C-reactive protein (CRP), albumin level (Alb), neutrophils (Neut), thrombocytes (Plt) and lymphocyte (Lym) count, Neut/Lym ratio were assessed. The volumes of the primary tumor (TV) and involved lymph nodes (NV) were calculated using MRI, CT or PET-CT scans. Data were analysed using parametric and nonparametric methods. Variables for multivariable linear regression analysis were chosen based on the results from univariable analysis (correlation, univariable regression and difference). There were 9 (18%), 10 (19%) and 32 (63%) patients who had TV and NV assessed in MRI, CT or PET respectively. Primary tumor neither as T-stage nor TV was related to ctHPV16 level. Significant differences in the ctHPV16 between patients with high vs low pain (P = 0.038), NV (P = 0.023), TV + NV (P = 0.018), CYFRA 21-1 (P = 0.002), CRP (P = 0.019), and N1 vs N3 (P = 0.044) were observed. ctHPV16 was significantly associated with CYFRA 21-1 (P = 0.017), N stage (P = 0.005), NV (P = 0.009), TV + NV (P = 0.002), CRP (P = 0.019), and pain (P = 0.038). In univariable linear regression analysis the same variables predicted ctHPV16 level. In multivariable analyses, CYFRA 21-1 and CRP (both as categorical variables) were predictors of ctHPV16 level even above NV. ctHPV16 at presentation is driven by tumor volume measured mostly by N. CYFRA 21-1 and CRP are additional factors related to ctHPV16 prior to the treatment.

Predicting HPV association using deep learning and regular H&E stains allows granular stratification of oropharyngeal cancer patients

Human Papilloma Virus (HPV)-associated oropharyngeal squamous cell cancer (OPSCC) represents an OPSCC subgroup with an overall good prognosis with a rising incidence in Western countries. Multiple lines of evidence suggest that HPV-associated tumors are not a homogeneous tumor entity, underlining the need for accurate prognostic biomarkers. In this retrospective, multi-institutional study involving 906 patients from four centers and one database, we developed a deep learning algorithm (OPSCCnet), to analyze standard H&E stains for the calculation of a patient-level score associated with prognosis, comparing it to combined HPV-DNA and p16-status. When comparing OPSCCnet to HPV-status, the algorithm showed a good overall performance with a mean area under the receiver operator curve (AUROC) = 0.83 (95% CI = 0.77-0.9) for the test cohort (n = 639), which could be increased to AUROC = 0.88 by filtering cases using a fixed threshold on the variance of the probability of the HPV-positive class - a potential surrogate marker of HPV-heterogeneity. OPSCCnet could be used as a screening tool, outperforming gold standard HPV testing (OPSCCnet: five-year survival rate: 96% [95% CI = 90-100%]; HPV testing: five-year survival rate: 80% [95% CI = 71-90%]). This could be confirmed using a multivariate analysis of a three-tier threshold (OPSCCnet: high HR = 0.15 [95% CI = 0.05-0.44], intermediate HR = 0.58 [95% CI = 0.34-0.98] p = 0.043, Cox proportional hazards model, n = 211; HPV testing: HR = 0.29 [95% CI = 0.15-0.54] p < 0.001, Cox proportional hazards model, n = 211). Collectively, our findings indicate that by analyzing standard gigapixel hematoxylin and eosin (H&E) histological whole-slide images, OPSCCnet demonstrated superior performance over p16/HPV-DNA testing in various clinical scenarios, particularly in accurately stratifying these patients.

β-CATENIN is a positive prognostic marker for HPV-positive head and neck squamous cell carcinoma

PURPOSE

The evolutionary-conserved Wnt/β-CATENIN (WBC) pathway has been implicated in the pathogenesis of different solid malignant tumors. We evaluated the prognostic relevance of β-CATENIN, a pivotal mediator of WBC activation, in patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC).

METHODS

We analyzed if patients with HPV-positive HNSCC from the "The Cancer Genome Atlas" (TCGA cohort, n = 41) can be stratified based on their CTNNB1 mRNA expression. Moreover, in a tissue microarray (TMA) of primary tumor sections from HPV-positive HNSCC patients treated in a tertiary academic center (in-house cohort, n = 31), we evaluated the prognostic relevance of β-CATENIN expression on protein level.

RESULTS

In silico mining of CTNNB1 expression in HPV-positive HNSCC revealed that high CTNNB1 expression was linked to better overall survival (OS, p = 0.062). Moreover, high β-CATENIN expression was significantly associated with a better OS in our in-house cohort (p = 0.035).

CONCLUSION

Based on these findings, we postulate that β-CATENIN expression could serve (potentially in conjunction with other WBC pathway members) as a marker for better survival outcomes in patients with HPV-positive HNSCC. However, it is evident that future studies on bigger cohorts are warranted.

Practical Application of Circulating Tumor-Related DNA of Human Papillomavirus in Liquid Biopsy to Evaluate the Molecular Response in Patients with Oropharyngeal Cancer

Recent findings have shown that human papillomavirus (HPV) DNA is present in the blood as a tumor-specific biomarker (circulating tumor-related HPV; ctHPV) in patients with HPV-related oropharyngeal cancer (HPV-related OPC). The molecular response (MR) in patients with HPV-related OPC can be defined as the change in the number of ctHPV copies in relation to its initial quantity. The optimal model for assessing the MR using a liquid biopsy (LB) should be based on the E6/E7 sequences of the viral genome. MR assessment can help to evaluate the intensity of ongoing treatments in relation to the tumor response. The evaluation of the residual disease at the end of therapy may also be performed by MR assessment. If a partial MR (pMR) is found, caution is indicated and a subsequent LB should be considered, due to the likelihood of disease progression. Complete radiological and clinical responses together with a complete MR (cMR) convincingly indicate a low risk of treatment failure. Moreover, molecular recurrence (Mrec) during a follow-up, confirmed in two consecutive assays, even despite the lack of any other clinical or radiological symptoms of progression, indicates patients at high risk of disease recurrence. In conclusion, MR by ctHPV assessment may hasten the early detection of disease progression, at any stage of the management of the patient with HPV-related OPC.

HPV status and HPV16 viral load in anal cancer and its association with clinical outcome

BACKGROUND

The incidence of anal cancer is increasing globally. Evidence-based improvement in early detection and management of this morbid cancer is thus required. In other cancers associated with Human Papillomavirus (HPV), viral status and dynamics, including viral load (VL) has been shown to influence clinical outcome. Our aim was to determine the influence of HPV status and HPV16 VL on the clinical outcomes of anal cancer patients.

METHODS

A total of 185 anal cancer lesions were genotyped for HPV. Of the HPV16 positive component, VL was determined using a digital droplet PCR assay. The association of qualitative HPV status and VL (low (<12.3), medium (12.3-57) and high (>57 copies/cell)) on overall survival and hazard of death was assessed.

RESULTS

Of the 185 cases, 164 (88.6%) samples were HPV positive. HPV16 was detected in 154/185 samples (83.2%). HPV positive status was associated with improved overall survival in the univariate analysis [hazard ratio (HR) of 0.44, 0.23-0.82, p = 0.01]. When adjusted by age, sex, stage and response to treatment, the association of positive HPV status with improved survival remained (HR 0.24 [0.11-0.55] p < 0.001). High VL was associated with improved overall survival in the univariate analysis with a HR of 0.28 (0.11-0.71, p = 0.007). When adjusted only by age and sex, high VL was associated with better overall survival (HR 0.27, 0.11-0.68 p = 0.006).

CONCLUSIONS

HPV status appears to be independently associated with improved outcomes in anal cancer patients. Moreover, HPV viral load quantification may be informative for further risk stratification and warrants further investigation.

Targeting Wnt/Beta-Catenin Signaling in HPV-Positive Head and Neck Squamous Cell Carcinoma

Wnt/Beta-Catenin signaling is involved in the carcinogenesis of different solid malignant tumors. The interaction of Creb-binding protein (CBP) with Beta-Catenin is a pivotal component of the Wnt/Beta-Catenin signaling pathway. The first aim of this study was to evaluate the association of CBP expression with survival in patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC). Second, the in vitro effects of the inhibition of CBP/Beta-Catenin interaction were analyzed. In particular, the effects of ICG-001, an inhibitor of CBP/Beta-Catenin interaction, on proliferation, cell death, modulation of Wnt/Beta-Catenin target expression, and cell migration were examined in vitro. High CBP expression is significantly associated with better survival on mRNA and protein levels. Furthermore, we observed cytotoxic as well as anti-migratory effects of ICG-001. These effects were particularly more potent in the HPV-positive than in the -negative cell line. Mechanistically, ICG-001 treatment induced apoptosis and led to a downregulation of CBP, c-MYC, and Cyclin D1 in HPV-positive cells, indicating inhibition of Wnt/Beta-Catenin signaling. In conclusion, high CBP expression is observed in HPV-positive HNSCC patients with a good prognosis, and ICG-001 showed a promising antineoplastic potential, particularly in HPV-positive HNSCC cells. Therefore, ICG-001 may potentially become an essential component of treatment de-escalation regimens for HPV-positive HNSCC. Further studies are warranted for additional assessment of the mechanistic background of our in vitro findings.

Understanding the Pattern of Oropharyngeal Cancers from North-East Romanian Patients

Background: Human papilloma virus (HPV) is acknowledged as a risk factor for oropharyngeal squamous cellular cancers (OPSCC), of which the dominant types are tonsillar (TSCC) and base of tongue cancer (BOTSCC). Objective: To assess the role of HPV in selected OPSCC cases, from Romanian patients by sensitive and complementary molecular assays. Material and Methods: Fifty-four formalin fixed paraffin embedded (FFPE) OPSCC samples were analyzed for HPV DNA by a PCR-based bead-based multiplex-assay. Thirty-four samples were tested for HPV RNA and for overexpression of p16INK4a by immunohistochemistry. Twenty samples were evaluated by Competitive Allele-Specific Taqman PCR (CAST-PCR) for fibroblast growth factor receptor 3 protein (FGFR3) status. Results: A total of 33.3% (18/54) OPSCC samples were positive for HPV DNA. HPV16 was the most frequent type (30%, 16/54); followed by HPV18 (3.7%, 2/54); and 1 sample (1.8%) was positive for both HPV16 and 18. HPV18 E6*I was detected in a HPV18 DNA-positive oropharynx tumor. Four samples positive for HPV16 were also positive for p16INK4a. All the tested samples were negative for FGFR3. Conclusions: The increased HPV16 prevalence is in line with similar studies and is a new confirmation that HPV16 is the most prevalent type in our country; supporting the potential benefit of prophylactic vaccines. Overall, there is no concordance between DNA and any of the two other analytes that are considered being markers of HPV-driven cancers. There is a need to explore novel screening strategies that could be broadly used in the clinical routine to initiate preventive measures.