De-Escalation Strategies for Human Papillomavirus-Associated Oropharyngeal Squamous Cell Carcinoma—Where Are We Now?

Cetuximab chemotherapy resistance: Insight into the homeostatic evolution of head and neck cancer (Review)

The complex evolution of genetic alterations in cancer that occurs in vivo is a selective process involving numerous factors and mechanisms. Chemotherapeutic agents that prevent the growth and spread of cancer cells induce selective pressure, leading to rapid artificial selection of resistant subclones. This rapid evolution is possible because antineoplastic drugs promote alterations in tumor‑cell metabolism, thus creating a bottleneck event. The few resistant cells that survive in this new environment obtain differential reproductive success that enables them to pass down the newly selected resistant gene pool. The present review aims to summarize key findings of tumor evolution, epithelial‑mesenchymal transition and resistance to cetuximab therapy in head and neck squamous cell carcinoma.

Survival outcomes in head and neck squamous cell carcinoma of unknown primary: A national cohort study

INTRODUCTION

To investigate factors influencing survival in head and neck squamous cell carcinoma of unknown primary (HNSCCUP).

METHODS

A retrospective observational cohort study was conducted, over 5 years from January 2015, in UK Head and Neck centres, of consecutive adults undergoing 18F-Fluorodeoxyglucose-PET-CT within 3 months of diagnosis with metastatic cervical squamous cell carcinoma. Patients treated as HNSCCUP underwent survival analysis, stratified by neck dissection and/or radiotherapy to the ipsilateral neck, and by HPV status.

RESULTS

Data were received from 57 centres for 965 patients, of whom 482 started treatment for HNSCCUP (65.7% HPV-positive, n = 282/429). Five-year overall survival (OS) for HPV-positive patients was 85.0% (95% CI 78.4-92.3) and 43.5% (95% CI 32.9-57.5) for HPV-negative. HPV-negative status was associated with worse OS, disease-free (DFS), and disease-specific (DSS) survival (all p < .0001 on log-rank test) but not local control (LC) (p = .16). Unilateral HPV-positive disease treated with surgery alone was associated with significantly worse DFS (p < .0001) and LC (p < .0001) compared to radiotherapy alone or combined modalities (5-year DFS: 24.9%, 82.3% and 94.3%; 5-year LC: 41.8%, 98.8% and 98.6%). OS was not significantly different (p = .16). Unilateral HPV-negative disease treated with surgery alone was associated with significantly worse LC (p = .017) (5-year LC: estimate unavailable, 93.3% and 96.6%, respectively). Small numbers with bilateral disease precluded meaningful sub-group analysis.

CONCLUSIONS

HPV status is associated with variable management and outcomes in HNSCCUP. Unilateral neck disease is treated variably and associated with poorer outcomes when managed with surgery alone. The impact of diagnostic oropharyngeal surgery on primary site emergence, survival and functional outcomes is unestablished.

Human Papilloma Virus Positive Oropharyngeal Squamous Cell Carcinoma and the Immune System: Pathogenesis, Immunotherapy and Future Perspectives

Oropharyngeal squamous cell carcinoma (OPSCC), a subset of head and neck squamous cell carcinoma (HNSCC), involves the palatine tonsils, soft palate, base of tongue, and uvula, with the ability to spread to adjacent subsites. Personalized treatment strategies for Human Papillomavirus-associated squamous cell carcinoma of the oropharynx (HPV+OPSCC) are yet to be established. In this article, we summarise our current understanding of the pathogenesis of HPV+OPSCC, the intrinsic role of the immune system, current ICI clinical trials, and the potential role of small molecule immunotherapy in HPV+OPSCC.

Long-read sequencing of oropharyngeal squamous cell carcinoma tumors reveal diverse patterns of high-risk Human Papillomavirus integration

Introduction

In North America and in most European countries, Human Papillomavirus (HPV) is responsible for over 70% of oropharyngeal squamous cell carcinomas. The burden of OPSCC, in high-income countries, has been steadily increasing over the past 20 years. As a result, in the USA and in the UK, the burden of HPV-related oropharyngeal squamous cell carcinoma in men has now surpassed that of cervical cancer in women. However, the oncogenic impact of high-risk HPV integration in oropharyngeal squamous cell carcinomas hasn't been extensively studied. The present study aimed to explore the patterns of HPV integration in oropharyngeal squamous cell carcinomas and to assess the feasibility and reliability of long-read sequencing technology in detecting viral integration events in oropharyngeal head and neck cancers.

Methods

A cohort of eight HPV-positive OPSCC pre-treatment patient tumors (four males and four females), were selected. All patients received a p16INK4A positive OPSCC diagnosis and were treated at the McGill University Health Centre, a quaternary center in Montreal. A minimum of 20mg of tumor tissue was used for DNA extraction. Extracted DNA was subjected to Nanopore long-read sequencing to detect and analyze for the presence of high-risk HPV sequences. PCR and Sanger sequencing experiments were performed to confirm Nanopore long-read sequencing readings.

Results

Nanopore long-read sequencing showed that seven out of eight patient samples displayed either integrated or episomal high-risk HPV sequences. Out of these seven samples, four displayed verifiable integration events upon bioinformatic analysis. Integration confirmation experiments were designed for all four samples using PCR-based methods. Sanger sequencing was also performed. Four distinct HPV integration patterns were identified: concatemer chromosomal integration in a single chromosome, bi-chromosomal concatemer integration, single chromosome complete integration and bi-chromosomal complete integration. HPV concatemer integration also proved more common than full HPV integration events.

Conclusion and relevance

Long-read sequencing technologies can be effectively used to assess HPV integration patterns in OPSCC tumors. Clinically, more research should be conducted on the prognostication value of high-risk HPV integration in OPSCC tumors using long-read sequencing technology.

Emerging Roles of Circulating Tumor DNA for Increased Precision and Personalization in Radiation Oncology

Recent breakthroughs in circulating tumor DNA (ctDNA) technologies present a compelling opportunity to combine this emerging liquid biopsy approach with the field of radiogenomics, the study of how tumor genomics correlate with radiotherapy response and radiotoxicity. Canonically, ctDNA levels reflect metastatic tumor burden, although newer ultrasensitive technologies can be used after curative-intent radiotherapy of localized disease to assess ctDNA for minimal residual disease (MRD) detection or for post-treatment surveillance. Furthermore, several studies have demonstrated the potential utility of ctDNA analysis across various cancer types managed with radiotherapy or chemoradiotherapy, including sarcoma and cancers of the head and neck, lung, colon, rectum, bladder, and prostate . Additionally, because peripheral blood mononuclear cells are routinely collected alongside ctDNA to filter out mutations associated with clonal hematopoiesis, these cells are also available for single nucleotide polymorphism analysis and could potentially be used to detect patients at high risk for radiotoxicity. Lastly, future ctDNA assays will be utilized to better assess locoregional MRD in order to more precisely guide adjuvant radiotherapy after surgery in cases of localized disease, and guide ablative radiotherapy in cases of oligometastatic disease.

The Tumor-Specific Immune Landscape in HPV+ Head and Neck Cancer

Human papillomaviruses (HPVs) are the causative agent of several anogenital cancers as well as head and neck cancers, with HPV+ head and neck squamous cell carcinoma (HNSCC) becoming a rapidly growing public health issue in the Western world. Due its viral etiology and potentially its subanatomical location, HPV+ HNSCC exhibits an immune microenvironment which is more inflamed and thus distinct from HPV-negative HNSCC. Notably, the antigenic landscape in most HPV+ HNSCC tumors extends beyond the classical HPV oncoproteins E6/7 and is extensively targeted by both the humoral and cellular arms of the adaptive immune system. Here, we provide a comprehensive overview of HPV-specific immune responses in patients with HPV+ HNSCC. We highlight the localization, antigen specificity, and differentiation states of humoral and cellular immune responses, and discuss their similarities and differences. Finally, we review currently pursued immunotherapeutic treatment modalities that attempt to harness HPV-specific immune responses for improving clinical outcomes in patients with HPV+ HNSCC.

Patient-Reported Outcome Measures of Psychosocial Quality of Life in Oropharyngeal Cancer Patients: A Scoping Review

Background: Oropharyngeal squamous cell carcinoma (OPSCC) patients are burdened by the effect of the disease process and treatment toxicities on organs important in everyday activities, such as breathing, speaking, eating, and drinking. There is a rise in OPSCC due to human papilloma virus (HPV)-associated OPSCC, affecting younger and healthier patients and with a better overall prognosis. Emphasis must be shared between oncologic outcomes and the effects on quality of life. While there have been efforts to study global and physical quality of life, the impact on psychosocial quality of life has not yet been specifically reviewed. Methods: A scoping review methodology was employed to explore the emotional, social, and mental quality of life in OPSCC patients and determine the impact of HPV status or treatment modalities. Results: Eighty-seven full-text articles were evaluated for eligibility. Fifteen articles met final inclusion criteria. The majority of the studies were conducted in the United States (n = 10) and study methodology was divided between cross-sectional (n = 6), prospective (n = 5), and retrospective studies (n = 4). Four psychosocial quality of life themes were explored: the impact on mental health and emotional wellbeing, social wellbeing and function, stress, and relationship and sexual behavior. Eighteen different patient-reported outcome measures were used, including both general head and neck oncology questionnaires and symptom-specific surveys. Conclusion: There is a paucity of research regarding the effect of OPSCC on patients' psychosocial quality of life. Learning more about this component of quality of life can guide outreach programs and multidisciplinary involvement in improving patient care.

Prognostic Significance of STING Immunoexpression in Relation to HPV16 Infection in Patients with Squamous Cell Carcinomas of Oral Cavity and Oropharynx

Infection with HPV16 in cancers of the oral cavity (OCSCC) and oropharynx (OPSCC) is, today, an important etiological and prognostic factor. Patients with HPV-positive OPSCC have a better prognosis than uninfected patients. However, in over 40% of these patients, cancer progression is noticed. Their identification is particularly important due to the ongoing clinical trials regarding the possibility of de-escalation of anticancer treatment in patients with HPV-positive OPSCC. Some studies suggest that there is possibility to differentiate prognosis of HPV16-positive patients by STING (Stimulator of Interferon Genes) immunoexpression. The aim of the present study was to analyze the influence of STING immunoexpression on overall (OS) and disease-free survival (DFS) of patients with HPV16-positive and -negative OCSCC and OPSCC. The study was performed in a group of 87 patients with OCSCC and OPSCC for which in our earlier study active HPV16 infection was assessed by P16 expression followed by HPV DNA detection. To analyze STING immunoexpression in tumor area (THS) and in adjacent stromal tissues (SHS) H score (HS) was applied. In the subgroup with HPV16, active infection patients with tumors with THS had significantly better DFS (p = 0.047) than those without THS. In this subgroup, TSH did not significantly influence OS, and SHS did not significantly correlate with OS and DFS. In the subgroup of patients without active HPV16 infection, THS and SHS also did not significantly influence patients' survival. Presented results indicated prognostic potential of tumor STING immunoexpression in patients with active HPV16 infection in cancers of oral cavity and oropharynx.

Low postoperative lymphocyte count increases risk of progression in human papillomavirus associated oropharyngeal cancer

BACKGROUND

We aim to explore the prognostic role of absolute lymphocyte count (ALC) before, during, and after treatment on oncologic outcomes in human papillomavirus associated oropharyngeal cancer (HPV(+)OPSCC).

METHODS

Retrospective cohort at a tertiary center, 2006-2018. Multivariable Cox regressions were used to determine the effect of ALC on risk of progression. Univariate linear regression was performed to determine clinical factors associated with lower ALC.

RESULTS

All 197 patients underwent primary surgery. Mean (SD) ALC nadirs (×10⁹  cells/L) were: baseline (N = 149): 1.69 (0.56); postoperative (N = 126): 1.58 (0.59); post-RT (N = 141): 0.68 (0.35) and long-term (N = 105): 0.88 (0.37). Lower baseline ALC nadir was associated with worse overall survival (HR 3.85, 95%CI: 1.03-14.29, p = 0.04). Lower postoperative ALC nadir was associated with higher risk of progression (HR 2.63, 95%CI: 1.04-6.67, p = 0.04).

CONCLUSIONS

Lower baseline ALC is associated with worse survival, whereas lower postoperative ALC is associated with increased risk of progression in surgically treated HPV(+)OPSCC.

LEVEL OF EVIDENCE: 3