Immunotherapy for Head and Neck Cancer: A Paradigm Shift From Induction Chemotherapy to Neoadjuvant Immunotherapy

Current Progress and Future Directions of Immunotherapy in Head and Neck Squamous Cell Carcinoma: A Narrative Review

Importance

For decades, the 3 therapeutic pillars for head and neck squamous cell carcinoma (HNSCC) have been radiation therapy, chemotherapy, and surgery. In recent years, a fourth pillar, immunotherapy, has shifted the existing paradigm of oncologic care by improving survival outcomes. This narrative review highlights key completed and ongoing clinical trials that have led to new therapeutic approaches and are aiming to further alter the current standard of care.

Observations

Immunotherapy in HNSCC first saw success in phase 3 clinical trials with immune checkpoint inhibitors (ICIs) for programmed cell death 1 protein in patients with recurrent or metastatic (R/M) disease. However, only approximately 15% to 20% of patients with R/M HNSCC achieve durable responses. Subsequent trials aimed to broaden ICIs to the definitive or curative setting, in combination with established chemoradiation modalities. These studies have yielded disappointing results, raising concerns that concurrent administration of ICI with chemoradiation- or radiation-induced attenuation of immune responses may contribute to lack of efficacy. Therefore, recent studies have attempted to introduce ICI sequentially, either prior to standard of care surgery in the neoadjuvant setting or following definitive treatment in the adjuvant or maintenance setting. These trials have demonstrated mixed results but with promising initial results from early phase neoadjuvant trials demonstrating early signals of response. Further trials are currently underway with various combinatorial approaches in the neoadjuvant and adjuvant settings to assess response rates and survival.

Conclusions and Relevance

The introduction of ICIs has brought a dramatic shift in the treatment landscape of HNSCC. Completed trials have provided new hope for patients, but failures in several settings suggest that further studies based on a biologic understanding of immune responses are required to expand immunotherapeutic approaches.

Sacituzumab Govitecan in Patients with Relapsed/Refractory Advanced Head and Neck Squamous Cell Carcinoma: Results from the Phase II TROPiCS-03 Basket Study

PURPOSE

Treatment options for advanced head and neck squamous cell carcinoma (HNSCC) previously treated with platinum-based chemotherapy and a PD-1 inhibitor are limited. Trophoblast cell-surface antigen 2 (Trop-2) is highly expressed in HNSCC. Sacituzumab govitecan (SG) is a Trop-2-directed antibody-drug conjugate approved for patients with certain previously treated solid tumors.

PATIENTS AND METHODS

TROPiCS-03 (NCT03964727) is an open-label, multicohort, phase II study evaluating SG in advanced solid tumors, including HNSCC. Adults with locally advanced or metastatic HNSCC that progressed following platinum-based chemotherapy and anti-PD-(L)1 therapy [given sequentially (either order) or in combination] were administered SG 10 mg/kg on days 1 and 8 of a 21-day cycle. The primary endpoint was the investigator-assessed objective response rate. Secondary endpoints included duration of response, clinical benefit rate, progression-free survival, overall survival, and safety.

RESULTS

Patients (N = 43) received a median of 3 (range, 2-9) prior anticancer regimens. The objective response rate was 16% [95% confidence interval (CI), 7%-31%], with seven confirmed partial responses. The clinical benefit rate was 28% (95% CI, 15%-44%). The median (95% CI) duration of response, progression-free survival, and overall survival were 4.2 (2.6-not reached), 4.1 (2.6-5.8), and 9.0 (7.1-10.5) months, respectively. The most common treatment-emergent adverse events (TEAE) were diarrhea (47%), nausea (47%), and neutropenia (47%). Grade ≥3 TEAE occurred in 58% of patients. Three patients died from TEAE, with one event (septic shock) considered related to SG.

CONCLUSIONS

These data demonstrate the clinical potential of Trop-2-directed therapy in managing heavily pretreated patients with advanced HNSCC.

Comment on "The characterization of tumor immune microenvironment after neoadjuvant immunotherapy in head and neck squamous cell cancer using multiplex immunohistochemistry"

This study in Oral Oncology highlights how neoadjuvant immunotherapy reshapes the tumor immune microenvironment (TIME) in HNSCC, increasing CD8+ T cells and reducing immunosuppressive cells. Using multiplex immunohistochemistry, it offers crucial spatial insights into TIME dynamics, paving the way for biomarker development and personalized therapies. Future research should explore combining this approach with single-cell technologies to elucidate functional immune states, enhancing our understanding of therapeutic responses and informing novel combinatorial treatment strategies.

Challenges in chemotherapy for head and neck cancer: A review

Head and neck cancer (HNC) remains a global health challenge due to its high mortality and morbidity. Advances in chemotherapy, combination therapies and targeted treatments like immunotherapy, have significantly improved survival rates. These developments pave the way for personalized therapies that maximize effectiveness while minimizing toxicities. However, challenges such as tumor resistance, treatment-related side effects and limited access to advanced therapies continue to hinder progress. Addressing these issues requires efforts in clinical research, biomarker discovery and ensuring equitable access to innovative treatments worldwide.

Spatial interaction mapping of PD-1/PD-L1 in head and neck cancer reveals the role of macrophage-tumour barriers associated with immunotherapy response

BACKGROUND

Mucosal head and neck squamous cell carcinoma (HNSCC) is often diagnosed at an advanced stage, where the prognosis is poor due to the high rates of recurrence and metastasis. With approximately one million new cases projected in 2024, worldwide mortality of HNSCC is estimated to reach 50% of detected cases the same year. Patients with early-stage tumours showed a 50-60% five-year survival rate in the US. Immune checkpoint inhibitors (ICIs) have shown promising results in prolonging survival in a subset of patients with recurrent or metastatic disease. However, challenges remain, particularly the limited efficacy of PD-1/PD-L1 blockade therapies. PD-L1 protein expression has been shown to be limited in its predictive power for ICI therapies. Emerging evidence shows that intricate characterisation of the tumour microenvironment (TME) is fundamental to understand interacting cells. This study aims to bridge the gap in understanding the tumor microenvironment by identifying distinct spatial patterns of PD-1/PD-L1 interactions and their association with immunotherapy responses in head and neck squamous cell carcinoma (HNSCC).

METHODS

In this study, we sought to apply a more nuanced approach to understanding cellular interactions by mapping PD-1/PD-L1 interactions across whole-slide HNSCC tissue samples collected prior to ICI therapy. We used a combination of spatial proteomics (Akoya Biosciences) and an in situ proximity ligation assay (isPLA, Navinci Diagnostics) to visualise PD-1/PD-L1 interactions across cell types and cellular neighbourhoods within the tumour TME.

RESULTS

Our findings indicate the existence of isPLA+ PD-1/PD-L1 interactions between macrophages/CD3 T cell-enriched neighbourhoods and tumour cells at the tumour-stroma boundaries in ICI-resistant tumours. The presence of these dense macrophage-tumour layers, which are either absent or dispersed in responders, indicates a barrier that may restrict immune cell infiltration and promote immune escape mechanisms. In contrast, responders had abundant B and T cell aggregates, predominantly around the tumour edges linked to enhanced immune responses to ICI therapy and better clinical outcomes.

CONCLUSION

This study highlights the utility of isPLA in detecting distinct tumour-immune interactions within the TME, offering new cellular interaction metrics for stratifying and optimising immunotherapy strategies.

Targeting macrophage migration inhibitory factor to inhibit T cell immunosuppression in the tumor microenvironment and improve cancer outcomes in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the 7th most common cancer globally with a 40-50 % survival rate. Although macrophage migration inhibitory factor (MIF) is overexpressed in most solid tumors and promotes tumor growth and invasion, the therapeutic potential of MIF inhibition in HNSCC is yet to be explored. In this study, we investigated the efficacy of CPSI-1306, a small-molecule MIF inhibitor, on HNSCC cell growth and cancer associated signaling pathways in vitro, as well as its impact on T cells in the HNSCC tumor microenvironment in vivo. CPSI-1306 did not reduce HNSCC cell proliferation in vitro, and mildly decreased VEGF and EGFR expression. However, CPSI-1306 significantly reduced tumor development in two orthotopic mouse oral cancer (MOC-2 and MOC-1) HNSCC models. Interestingly, CPSI-1306 treatment increased T cell infiltration to the tumor microenvironment and completely abrogated immunosuppressive checkpoint markers TIGIT, TIM3, and CTLA-4, but not PD-1 on tumor infiltrating CD8+ T cells. This was accompanied by increased CD8+ T cell expression of antitumoral cytokines IFN-γ and TNF-α in the draining lymph nodes and Granzyme B in the tumor microenvironment of CPSI-1306 treated tumor bearing mice. Our studies demonstrate that the small molecule MIF inhibitor CPSI-1306 potently inhibits T cell immunosuppression in the tumor microenvironment and reduces tumor growth in HNSCC. These studies open a novel therapeutic option for modulating anti-tumoral T cell immunity to improve HNSCC outcomes by targeting MIF.

Head & neck surgical oncology: Success in private practice

BACKGROUND

Due to its complexity and multimodality treatment needs, traditional delivery of head and neck cancer care often occurs in a multidisciplinary cancer center, frequently in a university-based program in an urban setting. Fellowship training opportunities for subspecialty-focused head and neck surgeons have increased over recent years. There is a persistent concern that the number of newly minted Head & Neck Surgeons graduating each year outpaces the number of university-based employment opportunities, and that the workforce does not match the job opportunities. Recent publications examine this potential mismatch to better understand career choices, with a 2021 survey revealing that nearly 90 % of fellowship graduates were employed by a university or academic institution and only 10 % reported being in "private practice". However, it should not be an automatic assumption that academic practice is somehow superior to private practice. Moreover, not every patient can access university-based care, creating a societal mismatch between disease incidence, resources, and access to high quality care. The well-trained Head & Neck Surgeon may be able to deliver excellent care in a satisfying practice setting without an academic affiliation.

METHODS

Two Head & Neck Surgeons who have practiced in both Academic and Community-based ("private") subspecialty settings offer practical and actionable tips to provide high level evidence-based head and neck surgical care without the trappings of a university, and with a focus on patient-centered care as well as career satisfaction. Further, since graduates of comprehensive otolaryngology training programs receive a robust amount of head and neck surgery training in residency, understanding these practical tips will potentially assist the Comprehensive Otolaryngologist in private practice to expand head and neck services within their practice.

OBJECTIVES

1) Review recently published survey-based reports of practice patterns and career satisfaction of recent HNS fellowship graduates, recognizing self-reported rates of practice settings, academic versus non-university-based ("private practice"). 2) Analyze and report practice structure of HNS graduates over the years 2015 to 2021 to determine rates of practice structure change from academic to private or vice versa, using Public Use Files combined with Google search. 3) Outline tips and pearls for a successful Head & Neck Surgery practice in a non-university-based setting, with 11 practical and actionable items that will allow high level subspecialty care without the traditional attributes of academic employment.

CONCLUSIONS

Graduates of head & neck surgery fellowships in recent years may perceive a paucity of academic job opportunities. This article reviews practice patterns of recent graduates, and presents practical tips to achieve a satisfying Head & Neck Surgery career in a private practice setting.

Correlation of immune profiling and exceptional response to immune checkpoint inhibitor in a patient with head and neck cancer

ABSTRACT

Immune checkpoint inhibitors (ICIs) have revolutionized the field of cancer therapy and it is a huge step forward in the treatment of various cancers including head and neck cancer. Nivolumab, an anti-PD-1 monoclonal antibody, reportedly has improved overall survival in head and neck cancer, yet only a subset of patient population benefit from it. Tissue-based markers such as PD-L1expression positive, tumor mutation burden-high, and microsatellite instability-high are widely believed to be a biomarker for ICIs such as nivolumab in solid tumors. However, due to the low prevalence of microsatellite instability-high and tumor mutation burden-high in most cancers and PD-L1 negative tumor responding well to ICIs, it tends to be insufficient to identify whether patients should receive ICIs as per this biomarker alone. Mechanism of response to checkpoint inhibitor therapy is unclear and hence studying the role of immune cells and pathways involved is important. The role played by peripheral blood parameters remains ambiguous. Here in, we present a case of an 85-year-old patient with advanced carcinoma buccal mucosa who was treated with Nivolumab after failure of chemotherapy and radiotherapy. Considering the limitations of tissue-based biomarkers to predict response to ICIs, we aimed to identify which blood-based biomarkers correlated with the response to treatment and monitored the immune parameters and serum cytokine levels during the course of Nivolumab. Here in, we also describe the clinical presentation of patient during the course of this therapy. Blood samples were collected pretherapy and post-therapy to monitor the response. Both clinical and immunological differences in the composition of Ki67+ PD-1+ CD8 T cells, Granzyme B+ CD8 T cells, NK and NKT cells, and serum cytokine levels of TNF alpha were observed to be elevated post-ICIs during monitoring of the patient receiving checkpoint inhibitor therapy. Monitoring these circulating peripheral blood markers in wider population of patients receiving ICI therapy, during its course, may provide a perspective in the development of new biomarkers for predicting response and may serve as a basis for personalized treatment. This case report describes valuable insights into evolution of immune markers predicting and monitoring response to Nivolumab in a patient with cancer.

Comprehensive review of post-treatment imaging in head and neck cancers: from expected to unexpected and beyond

Head and neck cancer management requires multidisciplinary approach in which radical surgery with or without flap reconstructions and neck dissection, along with radiotherapy (RT)/chemoradiotherapy (CRT) serve as the key components. Neoadjuvant chemotherapy and immunotherapy are used in selected cases based on the institutional preference. Knowledge of expected post-treatment changes on imaging is essential to differentiate it from recurrence. In addition, awareness of various post-treatment complications is imperative for their early detection on imaging. Distorted anatomy after treatment poses diagnostic challenge, hence, proper choice of imaging modality and appropriate timing of scan is pertinent for accurate post-treatment evaluation. In this article, we have comprehensively reviewed expected post-treatment appearances and complications on imaging. We have discussed imaging appearances of recurrences at the primary and lymphnodal sites and discussed documentation of findings using Neck Imaging Reporting and Data Systems (NI-RADS). We have also delved into the patterns of recurrence in human papillomavirus (HPV) positive HNSCC. Furthermore, we have provided flowcharts and discussed recommendations on the site-specific and treatment-related imaging modalities to be used along with their appropriate timing, for adequate evaluation of HNSCC after treatment. In addition, we have also touched upon the role of advanced imaging techniques for post-treatment HNSCC evaluation.

Preventive effects of melatonin and amifostine on irradiated rats with experimental periodontitis

BACKGROUND

The aim of this study was to investigate the preventive effects of amifostine and melatonin oxidatively, biochemically and histomorphometrically in rats with radiotherapy-induced experimental periodontitis.

METHODS

40 female Sprague-Dawley rats were divided into 5 groups: Control, experimental periodontitis (Ep), Ep + radiotherapy (Ep + Rt), Ep + Rt + amifostine (Ep + Rt + Ami), Ep + Rt + melatonin (Ep + Rt + Mel). The day after induction of periodontitis by ligature, a single dose of 5 Gy radiotherapy was administered. On the same day, treatments with amifostine (200 mg/kg) for 3 days and melatonin (10 mg/kg) for 15 days were started. By after 23 days of experiment, periodontal bone loss was measured by histomorphometry. RANKL, OPG and Caspase-3 activities were analyzed immunohistochemically and inflammatory cytokine (IL-1β, IL-10, IL-6, TNF-α) levels and oxidative stress (TOS/TAS) were analyzed biochemically in tissue homogenates.

RESULTS

It was observed that there was a significant difference in many biochemical parameters and oxidative stress levels between the control group and Ep + Rt (p < 0.05). Alveolar bone destruction in the melatonin prophylaxis group was observed to be close to control (p > 0.05). Melatonin significantly improved biochemical, histochemical, apoptotic and bone loss levels in irradiated experimental periodontitis rats (p < 0.05). When comparing the two drug groups (Ep + Rt + Ami and Ep + Rt + Mel), no statistically significant difference was found at any parameter level (p > 0.05).

CONCLUSION

Both melatonin and amifostine can significantly limit RT-induced periodontal bone loss by suppressing inflammatory stress, apoptotic mechanisms, and RANKL-related osteoclastic activity. Given the limited side effects of melatonin, it may be an alternative to amifostine.

Unveiling Biomarkers in Head and Neck Squamous Cell Carcinoma through Bioinformatics: The Role of SPP1 and KRT78

Head and neck squamous cell carcinoma (HNSCC) is the most common form of head and neck cancer, ranking sixth in global cancer incidence. Identifying molecular drivers of tumorigenesis and metastasis is essential for early detection and treatment. This study analyzed gene expression profiles from three datasets (GSE6791, GSE29330, and GSE58911) to identify differentially expressed genes (DEGs) in HNSCC. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were employed to functionally annotate these DEGs. A protein-protein interaction (PPI) network was constructed for selecting hub genes using the STRING database. Finally, hub gene and protein expression levels were evaluated in patients with HNSCC, along with their association with overall survival. Our analysis identified twenty-eight co-DEGs comprising eight up-regulated and twenty down-regulated genes, primarily involved in extracellular matrix (ECM) organization, proteolysis, ECM disassembly, and keratinization processes. Furthermore, the PPI network revealed eight hub genes based on their high degree of connectivity. Notably, SPP1 demonstrated up-regulation, while KRT78 was down-regulated in HNSCC. Remarkably, the expression levels of these hub genes correlated with tumor grade, clinical cancer stage, and poor prognosis in HNSCC. Our findings hold significant clinical potential for early diagnosis and the development of novel therapeutic targets for patients with HNSCC.

Localized intratumoral delivery of immunomodulators for oral cancer and oral potentially malignant disorders

Immunotherapy has developed into an important modality of modern cancer treatment. Unfortunately, checkpoint inhibitor immunotherapies are currently delivered systemically and require frequent administration, which can result in toxicity and severe, sometimes fatal, adverse events. Localized delivery of immunomodulators for oral cancer and oral potentially malignant disorders offers the promise of maximum therapeutic potential and reduced systemic adverse effects. This review will discuss the limitations of current standard-of-care systemic therapies and highlight research advances in localized, intratumoral delivery platforms for immunotherapy for oral cancer and oral potentially malignant disorders.

A Review of Immunotherapy for Head and Neck Cancer

The introduction of immune checkpoint inhibitors (ICIs) to oncological care has transformed the management of various malignancies, including head and neck squamous cell carcinoma (HNSCC), offering improved outcomes. The first-line treatment of recurrent and malignant HNSCC for many years was combined platinum, 5-fluorouracil, and cetuximab. Recently, the ICI pembrolizumab was approved as a first-line treatment, with or without chemotherapy, based on tumor and immune cell percentage of programmed-death ligand 1 (PD-L1). Multiple head and neck (HN) cancer trials have subsequently explored immunotherapies in combination with surgery, chemotherapy, and/or radiation. Immunotherapy regimens may be personalized by tumor biomarker, including PD-L1 content, tumor mutational burden, and microsatellite instability. However, further clinical trials are needed to refine biomarker-driven protocols and standardize pathological methods to guide combined regimen timing, sequencing, and deescalation. Gaps remain for protocols using immunotherapy to reverse oral premalignant lesions, particularly high-risk leukoplakias. A phase II nonrandomized controlled trial, using the ICI nivolumab, showed a 2-y cancer-free survival of 73%, although larger trials are needed. Guidelines are also needed to standardize the role of dental evaluation and care before, during, and after immunotherapy, specifically in regard to oral immune-related adverse events and their impact on cancer recurrence. Standardized diagnostic and oral care coordination strategies to close these gaps are needed to ensure continued success of HN cancer immunotherapy.

Epigenetic modification in radiotherapy and immunotherapy for cancers

Radiotherapy (RT) is one of the primary treatment modalities in managing cancer patients. Recently, combined RT and immunotherapy (IT) (i.e., radio-IT [RIT]) have been aggressively investigated in managing cancer patients. However, several issues in conducting RIT are challenging, such as incorporating advanced irradiation techniques, predictive/prognostic biomarkers, and other treatment modalities. Several clinical efforts and novel biomarkers have been introduced and developed to solve these challenges. For example, stereotactic radiosurgery/stereotactic radiotherapy, stereotactic body radiotherapy/stereotactic ablative body radiotherapy, and FLASH-RT have been applied for delivering precise irradiation to lung and liver tumors in conjunction with IT. Besides, several novel IT agents and incorporations of other therapies, such as targeted and thermal therapies, have been further investigated. The present study reviewed the emerging challenges of RIT in modern oncology. We also evaluated clinical practice, bench research, and multimodality treatments. In addition to several clinically applicable biomarkers, we emphasize the roles of advanced irradiation techniques and epigenetic modification as predictive/prognostic biomarkers and potential therapeutic targets. For example, 6(m) A-based epigenetic agents demonstrate the potential to enhance the treatment effects of RIT. However, further prospective randomized trials should be conducted to confirm their roles.

Less is more: Exploring neoadjuvant immunotherapy as a de-escalation strategy in head and neck squamous cell carcinoma treatment

Head and neck squamous cell carcinoma (HNSCC) constitutes a significant global cancer burden, given its high prevalence and associated mortality. Despite substantial progress in survival rates due to the enhanced multidisciplinary approach to treatment, these methods often lead to severe tissue damage, compromised function, and potential toxicity. Thus, there is an imperative need for novel, effective, and minimally damaging treatment modalities. Neoadjuvant treatment, an emerging therapeutic strategy, is designed to reduce tumor size and curtail distant metastasis prior to definitive intervention. Currently, neoadjuvant chemotherapy (NACT) has optimized the treatment approach for a subset of HNSCC patients, yet it has not produced a noticeable enhancement in overall survival (OS). In the contemporary cancer therapeutics landscape, immunotherapy is gaining traction at an accelerated pace. Notably, neoadjuvant immunotherapy (NAIT) has shown promising radiological and pathological responses, coupled with encouraging efficacy in several clinical trials. This potentially paves the way for a myriad of possibilities in treatment de-escalation of HNSCC, which warrants further exploration. This paper reviews the existing strategies and efficacies of neoadjuvant immune checkpoint inhibitors (ICIs), along with potential de-escalation strategies. Furthermore, the challenges encountered in the context of the de-escalation strategies of NAIT are explored. The aim is to inform future research directions that strive to improve the quality of life (QoL) for patients battling HNSCC.

Safety and clinical activity of durvalumab combined with tremelimumab in recurrent/metastatic head and neck squamous cell carcinoma: a multicenter phase I study

BACKGROUND

Programmed cell death protein 1 (PD-1) inhibitors prolong survival versus chemotherapy in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC), which often expresses cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death-ligand 1 (PD-L1), providing a rationale for combined PD-(L)1 and CTLA-4 blockade. We report a phase I, open-label study of the PD-L1 inhibitor durvalumab plus the CTLA-4 inhibitor tremelimumab (NCT02262741).

METHODS

In dose exploration, two cohorts of previously treated patients received durvalumab 10 mg/kg plus tremelimumab 3 mg/kg, or durvalumab 20 mg/kg plus tremelimumab 1 mg/kg, for up to 12 months. Dose expansion comprised two cohorts of previously untreated patients with R/M HNSCC having baseline PD-L1 tumor cell (TC) expression ≥25% and <25% and one cohort of immunotherapy-pretreated patients with any PD-L1 level. All received durvalumab 20 mg/kg plus tremelimumab 1 mg/kg, then durvalumab 10 mg/kg, for up to 12 months. The primary endpoint was safety. The secondary endpoints were objective response rate (ORR) by RECIST version 1.1, pharmacokinetics, pharmacodynamics, and immunogenicity.

RESULTS

A total of 71 patients were treated. The median duration of exposure was 13.6 weeks for durvalumab and 13.1 weeks for tremelimumab. In dose exploration, no dose-limiting toxicities occurred. No maximum tolerated dose was identified. Treatment-related adverse events (TRAEs) occurred in 69.0% of patients; grade 3/4 and serious TRAEs occurred in 31.0% and 18.3%, respectively. TRAEs led to discontinuation in 9.9%. There were no treatment-related deaths. The ORR was 5.6% (95% confidence interval 1.6-13.8), including one complete response and three partial responses, all patients were in dose expansion with PD-L1 TC ≥25% and no prior immunotherapy exposure; three had ongoing responses ≥12 months. The median overall survival in the total population was 8.6 months. Soluble PD-L1 suppression was almost complete in all cohorts, suggesting target engagement. CD4+Ki67+ T cells were significantly elevated in all dose-expansion cohorts.

CONCLUSIONS

Treatment was well tolerated. However, response rates were low despite target engagement, no drug-drug interactions, and no drug-neutralizing antibodies to durvalumab.

Survival and complications after carotid resection for head and neck squamous cell carcinoma: A systematic review and pooled analysis

OBJECTIVE

The aim of this study is to analyze oncologic outcomes and complications rate after common or internal carotid artery (CCA/ICA) resection for head and neck squamous cell carcinoma (HNSCC).

METHODS

This study was conducted in conformity with the PRISMA statement. A systematic review and pooled analysis was performed for overall survival (OS), disease specific survival (DSS) (primary outcomes), and perioperative death rate (secondary outcome).

RESULTS

A total of 276 patients (males: 76.7%, n = 191/249) with a median age of 59 years (n = 239/276; 95% CI 55.0-61.7) who underwent CCA/ICA resection for HNSCC were included. The median follow-up time was 11 months (n = 276). Estimated pooled OS rates (95% CI) at 1 and 2 years were 52.7% (46.9-59.2) and 29.8% (24.3-36.5), respectively. The median OS (95% CI) was 14 months (12-17). Estimated pooled DSS rates (95% CI) at 1 and 2 years were 58.6% (52.7-65.2) and 34.6% (28.5-41.9), respectively. The median DSS (95% CI) was 16 months (14-19). The perioperative death rate was 6.9% (n = 19/276).

CONCLUSIONS

CCA/ICA resection should be considered as a treatment option for accurately selected patients. Multicentric prospective studies are recommended to develop a predictive score guiding the decision-making process.

Histological pattern of tumor inflammation and stromal density correlate with patient demographics and immuno-oncologic transcriptional profile in oral squamous cell carcinoma

Introduction

Oral squamous cell carcinoma (OSCC) is the most prevalent oral malignancy, with emerging interest in the characterization of its tumor microenvironment. Herein, we present a comprehensive histological analysis of OSCC stromal density and inflammation and their relationship with patient demographics, clinicopathologic features and immuno-oncologic signatures.

Materials-methods

Eighty-seven completely excised OSCC tissues were prospectively collected and scored for histopathologic inflammatory subtypes [HIS]-inflamed (INF), immune-excluded (IE) and immune-desert (ID), peritumoral stromal inflammation (PTSI), and peritumoral stromal fibrosis (PTSF). Scoring of inflammation was complemented by Semaphorin 4D immunohistochemistry. NanoString differential gene expression (DGE) analysis was conducted for eight OSCC cases representative of the inflammatory and stromal subtypes and the demographic groups.

Results

PTSF correlated with male gender (p = 0.0043), smoking (p = 0.0455), alcohol consumption (p = 0.0044), increased tumor size (p = 0.0054), and advanced stage (p = 0.002). On the contrary, PTSI occurred predominantly in females (p = 0.0105), non-drinkers (p = 0.0329), and small tumors (p = 0.0044). Transcriptionally, decreased cytokine signaling, and oncogenic pathway activation were observed in HIS-IE. Smokers and males displayed decreased global immune-cell levels and myeloid-cell predominance.

Conclusion

Our work describes OSCC stromal and inflammatory phenotypes in correlation with distinct patient groups and DGE, highlighting the translational potential of characterizing the tumor microenvironment for optimal patient stratification.

Immunomethylomic profiles of long-term head and neck squamous cell carcinoma survivors on immune checkpoint inhibitors

Aim: This study addresses the challenge of predicting the response of head and neck squamous cell carcinoma (HNSCC) patients to immunotherapy.Methods: Using DNA methylation cytometry, we analyzed the immune profiles of six HNSCC patients who showed a positive response to immunotherapy over a year without disease progression.Results: There was an initial increase in CD8 T memory cells and natural killer cells during the first four cycles of immunotherapy, which then returned to baseline levels after a year. Baseline CD8 T cell levels were lower in HNSCC immunotherapy responders but became similar to those in healthy subjects after immunotherapy.Conclusion: These findings suggest that monitoring fluctuations in immune profiles could potentially identify biomarkers for immunotherapy response in HNSCC patients.

Indicators to evaluate quality of care in head and neck cancer in Spain

PURPOSE

This study aimed to develop a set of criteria and indicators to evaluate the quality of care of patients with head and neck cancer (HNC).

METHODS

A systematic literature review was conducted to identify valuable criteria/indicators for the assessment of the quality of care in HNC. With the aid of a technical group, a scientific committee of oncologists specialised in HNC used selected criteria to propose indicators that were evaluated with a two-round Delphi method. Indicators on which consensus was achieved were then prioritised by the scientific committee to develop a final set of indicators.

RESULTS

We proposed a list of 50 indicators used in the literature or developed by us to be evaluated with a Delphi method. There was consensus on the appropriateness of 47 indicators in the first round; the remaining 3 achieved consensus in the second round. The 50 indicators were scored to prioritise them, leading to a final selection of 29 indicators related to structure (3), process (22), or outcome (4) and covering diagnosis, treatment, follow-up, and health outcomes in patients with HNC. Easy-to-use index cards were developed for each indicator, with their criterion, definition, formula for use in real-world clinical practice, rationale, and acceptable level of attainment.

CONCLUSIONS

We have developed a set of 29 evidence-based and expert-supported indicators for evaluating the quality of care in HNC, covering diagnosis, treatment, follow-up, and health outcomes.

Rethinking treatment paradigms: Neoadjuvant therapy and de-escalation strategies in HPV-positive head and neck cancer

Head and neck cancer (HNC) is the 6th most common cancer across the world, with a particular increase in HNC associated with human papilloma virus (HPV) among younger populations. Historically, the standard treatment for this disease consisted of combined surgery and radiotherapy or curative platinum-based concurrent chemoradiotherapy, with associated long term and late toxicities. However, HPV-positive HNC is recognized as a unique cancer subtype, typically with improved clinical outcomes. As such, treatment de-escalation strategies have been widely researched to mitigate the adverse effects associated with the current standard of care without compromising efficacy. These strategies include treatment de-escalation, such as novel surgical techniques, alternative radiation technologies, radiation dose and volume reduction, as well as neoadjuvant chemotherapies, immunotherapies, and combined therapies. Although these therapies show great promise, many of them are still under investigation due to hesitation surrounding their widespread implementation. The objective of this review is to summarize the most recent progress in de-escalation strategies and neoadjuvant therapies designed for HPV-positive HNC. While specific treatments may require additional research before being widely adopted, encouraging results from recent studies have highlighted the advantages of neoadjuvant chemotherapy and immunotherapy, as well as radiation and surgical de-escalation approaches in managing HPV-positive HNC.

Unique vulnerability of RAC1-mutant melanoma to combined inhibition of CDK9 and immune checkpoints

RAC1P29S is the third most prevalent hotspot mutation in sun-exposed melanoma. RAC1 alterations in cancer are correlated with poor prognosis, resistance to standard chemotherapy, and insensitivity to targeted inhibitors. Although RAC1P29S mutations in melanoma and RAC1 alterations in several other cancers are increasingly evident, the RAC1-driven biological mechanisms contributing to tumorigenesis remain unclear. Lack of rigorous signaling analysis has prevented identification of alternative therapeutic targets for RAC1P29S-harboring melanomas. To investigate the RAC1P29S-driven effect on downstream molecular signaling pathways, we generated an inducible RAC1P29S expression melanocytic cell line and performed RNA-sequencing (RNA-seq) coupled with multiplexed kinase inhibitor beads and mass spectrometry (MIBs/MS) to establish enriched pathways from the genomic to proteomic level. Our proteogenomic analysis identified CDK9 as a potential new and specific target in RAC1P29S-mutant melanoma cells. In vitro, CDK9 inhibition impeded the proliferation of in RAC1P29S-mutant melanoma cells and increased surface expression of PD-L1 and MHC Class I proteins. In vivo, combining CDK9 inhibition with anti-PD-1 immune checkpoint blockade significantly inhibited tumor growth only in melanomas that expressed the RAC1P29S mutation. Collectively, these results establish CDK9 as a novel target in RAC1-driven melanoma that can further sensitize the tumor to anti-PD-1 immunotherapy.

The clinical outcome of pembrolizumab for patients with recurrent or metastatic squamous cell carcinoma of the head and neck: a single center, real world study in China

Background

The KEYNOTE-048 and KEYNOTE-040 study have demonstrated the efficacy of pembrolizumab in recurrent or metastatic squamous cell carcinoma of the head and neck (R/M HNSCC), we conducted this real-world study to investigate the efficacy of pembrolizumab in patients with R/M HNSCC.

Methods

This is a single-center retrospective study conducted in the Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (Shanghai, China). Between December 2020 and December 2022, a total of 77 patients with R/M HNSCC were included into analysis. The primary endpoint of the study was overall survival (OS), and the secondary endpoints were progression-free survival (PFS), overall response rate (ORR)and toxicity.Efficacy was assessed according to RECIST version 1.1.SPSS 27.0 and GraphPad Prism 8.0 software were utilized to perform the statistical analysis.

Results

By the cut-off date (February 28, 2023), the median OS,PFS and ORR were 15.97 months,8.53 months and 48.9% in patients treated with the pembrolizumab regimen in the first line therapy. Among these patients, 17 patients received pembrolizumab with cetuximab,and 18 received pembrolizumab with chemotherapy.We observed no significant differences between two groups neither in median OS (13.9 vs 19.4 months, P=0.3582) nor PFS (unreached vs 8.233 months, P= 0.2807). In the ≥2nd line therapy (n=30), the median OS, PFS and ORR were 5.7 months, 2.58 months and 20% respectively. Combined positive score (CPS) was eligible from 54 patients. For first line therapy, the median OS and PFS were 14.6 and 8.53 months in patients with CPS ≥1, and median OS and PFS were 14.6 and 12.33 months in patients with CPS ≥20. The immune-related adverse events (irAEs) were occurred in the 31 patients (31/77, 40.26%), and the most common potential irAEs were hypothyroidism (25.97%), and pneumonitis (7.79%).

Conclusion

Our real-world results indicated that pembrolizumab regimen is a promising treatment in patients with R/M HNSCC.

Global research trends in tongue cancer from 2000 to 2022: bibliometric and visualized analysis

OBJECTIVES

This study conducts a systematic bibliometric analysis of tongue cancer publications to identify key topics, hotspots, and research distribution.

METHODS

We analyzed tongue cancer publications in the Web of Science core collection database, assessing their quantity and quality. We investigated contributors, including countries, affiliations, journals, authors, and categories, within collaborative networks. Additionally, we synthesized key research findings using various analytical techniques, such as alluvial flow, burstness analysis, cluster analysis, co-occurrence network of associations, and network layer overlay.

RESULTS

From 2000 to 2022, this bibliometric study covers 2205 articles and reviews across 617 journals, involving 72 countries, 2233 institutions, and 11,266 authors. It shows consistent growth, particularly in 2016. Key contributors include China (499 publications), Karolinska Institute (84 publications), Oral Oncology (144 publications), and Tuula Salo (47 publications). Other notable contributors are the USA (16,747 citations), the National Cancer Institute (NCI) (2597 citations), and the Memorial Sloan-Kettering Cancer Center (MSK) (2231 citations). Additionally, there are significant teams led by Tuula Salo and Dalianis. We have identified six primary clusters: #0 apoptosis, #1 depth of invasion, #2 radiotherapy, #3 hpv, #4 tongue cancer, #5 oral cancer. The top ten highly cited documents primarily pertain to epidemiology, prognostic indicators in early-stage oral tongue cancer, and HPV. Additionally, we observed 16 reference clusters, with depth of invasion (#3), young patients (#4), and tumor budding (#6) gaining prominence since 2012, indicating sustained research interests.

CONCLUSIONS

This analysis emphasizes the increasing scholarly interest in tongue cancer research. The bibliometric evaluation highlights pivotal recent research themes such as HPV, depth of invasion, tumor budding, and surgical margins.

CLINICAL RELEVANCE

The bibliometric analysis highlights the key topics and studies which have shaped the understanding and management of tongue cancer.

Oral Surgery and Osteoradionecrosis in Patients Undergoing Head and Neck Radiation Therapy: An Update of the Current Literature

Osteoradionecrosis (ORN) is a serious long-term complication of head and neck radiotherapy (RT), which is often triggered by dental extractions. It results from avascular aseptic necrosis due to irradiated bone damage. ORN is challenging to treat and can lead to severe complications. Furthermore, ORN causes pain and distress, significantly reducing the patient's quality of life. There is currently no established preventive strategy. This narrative review aims to provide an update for the clinicians on the risk of ORN associated with oral surgery in head and neck RT patients, with a focus on the timing suitable for the oral surgery and possible ORN preventive treatments. An electronic search of articles was performed by consulting the PubMed database. Intervention and observational studies were included. A multidisciplinary approach to the patient is highly recommended to mitigate the risk of RT complications. A dental visit before commencing RT is highly advised to minimize the need for future dental extractions after irradiation, and thus the risk of ORN. Post-RT preventive strategies, in case of dento-alveolar surgery, have been proposed and include antibiotics, hyperbaric oxygen (HBO), and the combined use of pentoxifylline and tocopherol ("PENTO protocol"), but currently there is a lack of established standards of care. Some limitations in the use of HBO involve the low availability of HBO facilities, its high costs, and specific clinical contraindications; the PENTO protocol, on the other hand, although promising, lacks clinical trials to support its efficacy. Due to the enduring risk of ORN, removable prostheses are preferable to dental implants in these patients, as there is no consensus on the appropriate timing for their safe placement. Overall, established standards of care and high-quality evidence are lacking concerning both preventive strategies for ORN as well as the timing of the dental surgery. There is an urgent need to improve research for more efficacious clinical decision making.

Differences in Receipt of Immunotherapy Treatment Among Patients With Head and Neck Cancer

Importance

The US Food and Drug Administration approved immune checkpoint inhibitors (immunotherapy) for select cases of head and neck squamous cell carcinoma (HNSCC) in 2016. However, it is unclear whether there are clinical or sociodemographic differences among patients receiving immunotherapy as part of their care. Given the known disparities in head and neck cancer care, we hypothesized that there are differences in receipt of immunotherapy among patients with HNSCC based on clinical and nonclinical characteristics.

Objective

To characterize clinical and nonclinical factors associated with receipt of immunotherapy among older patients with HNSCC.

Design, Setting, and Participants

This retrospective cohort study included patients 65 years or older diagnosed with HNSCC (n = 4860) in a community oncology care setting. Electronic health records from Navigating Cancer were assessed from January 1, 2017, to April 30, 2022.

Main Outcomes and Measures

Multivariable logistic regression was used to characterize clinical (tumor stage [localized vs advanced] and anatomical subsite [oropharyngeal vs nonoropharyngeal]) and nonclinical (age, smoking history, race and ethnicity, sex, and marital status) factors associated with receipt of immunotherapy.

Results

In the study cohort of 4860 patients, 3593 (73.9%) were men; 4230 (87.0%) were White and 630 (13.0%) were of other races. A total of 552 patients (11.4%) had received immunotherapy. After adjusting for covariates, in the final model, White patients with HNSCC had 80% increased odds of receiving immunotherapy (adjusted odds ratio [AOR], 1.80 [95% CI, 1.30-2.48]) compared with patients of other races. There were no statistically significant differences in the odds of receiving immunotherapy based on age, sex, or smoking history. Patients with nonoropharyngeal disease were significantly more likely to receive immunotherapy than those with oropharyngeal cancer (AOR, 1.29 [95% CI, 1.05-1.59]), as were those with advanced compared with local disease (AOR, 2.39 [95% CI, 1.71-3.34]).

Conclusions and Relevance

The findings of this cohort study suggest that among older patients with HNSCC, White patients may be more likely to receive immunotherapy as part of their care. Equitable access to immunotherapy and other treatment options will reduce cancer-related health disparities and improve survival of patients with HNSCC.

Differentially Expressed Genes, miRNAs and Network Models: A Strategy to Shed Light on Molecular Interactions Driving HNSCC Tumorigenesis

Head and neck squamous cell carcinoma (HNSCC) is among the most common cancer worldwide, accounting for hundreds thousands deaths annually. Unfortunately, most patients are diagnosed in an advanced stage and only a percentage respond favorably to therapies. To help fill this gap, we hereby propose a retrospective in silico study to shed light on gene-miRNA interactions driving the development of HNSCC. Moreover, to identify topological biomarkers as a source for designing new drugs. To achieve this, gene and miRNA profiles from patients and controls are holistically reevaluated using protein-protein interaction (PPI) and bipartite miRNA-target networks. Cytoskeletal remodeling, extracellular matrix (ECM), immune system, proteolysis, and energy metabolism have emerged as major functional modules involved in the pathogenesis of HNSCC. Of note, the landscape of our findings depicts a concerted molecular action in activating genes promoting cell cycle and proliferation, and inactivating those suppressive. In this scenario, genes, including VEGFA, EMP1, PPL, KRAS, MET, TP53, MMPs and HOXs, and miRNAs, including mir-6728 and mir-99a, emerge as key players in the molecular interactions driving HNSCC tumorigenesis. Despite the heterogeneity characterizing these HNSCC subtypes, and the limitations of a study pointing to relationships that could be context dependent, the overlap with previously published studies is encouraging. Hence, it supports further investigation for key molecules, both those already and not correlated to HNSCC.

Photoactivated HPPH-Liposomal therapy for the treatment of HPV-Negative head and neck cancer

OBJECTIVES

Human Papillomavirus (HPV)-negative head and neck cancer (HNC) is an aggressive malignancy with a poor prognosis. To improve outcomes, we developed a novel liposomal targeting system embedded with 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), a chlorin-based photosensitizer. Upon exposure to 660 nm light, HPPH phototriggering generates reactive oxygen species. The objective of this study was to evaluate biodistribution and test efficacy of HPPH-liposomal therapy in a patient-derived xenograft (PDX) model of chemoradioresistant HNC.

MATERIALS AND METHODS

PDX models were developed from two surgically resected HNCs (P033 and P038) recurrent after chemoradiation. HPPH-liposomes were created including trace amounts of DiR (Ex/Em 785/830 nm), a near infrared lipid probe. Liposomes were injected via tail vein into PDX models. Biodistribution was assessed at serial timepoints in tumor and end-organs through in vivo DiR fluorescence. To evaluate efficacy, tumors were treated with a cw-diode 660 nm laser (90 mW/cm2, 5 min). This experimental arm was compared to appropriate controls, including HPPH-liposomes without laser or vehicle with laser alone.

RESULTS

HPPH-liposomes delivered via tail vein exhibited selective tumor penetration, with a peak concentration at 4 h. No systemic toxicity was observed. Treatment with combined HPPH-liposomes and laser resulted in improved tumor control relative to either vehicle or laser alone. Histologically, this manifested as both increased cellular necrosis and decreased Ki-67 staining in the tumors treated with combined therapy.

CONCLUSIONS

These data demonstrate tumor-specific anti-neoplastic efficacy of HPPH-liposomal treatment for HNC. Importantly, this platform can be leveraged in future studies for targeted delivery of immunotherapies which can be packaged within HPPH-liposomes.

Toll-like Receptor Agonists Are Unlikely to Provide Benefits in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

Recurrent and metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) has poor survival rates. Immunotherapy is the standard of care for R/M HNSCC, but objective responses occur in a minority of patients. Toll-like receptor (TLR) agonists promote antitumor immune responses and have been explored in clinical trials.

METHODS

A search for clinical trials using TLR agonists in HNSCC was performed under PRISMA guidelines. Data on patient characteristics, safety, and efficacy were collected and analyzed.

RESULTS

Three phase 1b trials with 40 patients and three phase 2 trials with 352 patients studying TLR8 and TLR9 agonists in combination with other treatment regimens for HNSCC were included. In phase 2 trials, there was no significant change in the objective response rate (RR = 1.13, CI 0.80-1.60) or association with increased grade 3+ adverse events (RR = 0.91, CI 0.76-1.11) associated with TLR agonist use.

CONCLUSION

TLR agonists do not appear to provide additional clinical benefits or increase adverse events in the treatment of HNSCC. Given these results across multiple clinical trials and drug regimens, it is unlikely that additional trials of TLR agonists will demonstrate clinical benefits in HNSCC.

Expanding the role of combined immunochemotherapy and immunoradiotherapy in the management of head and neck cancer (Review)

Immunotherapy has become one of the most promising approaches in tumor therapy, and there are numerous associated clinical trials in China. As an immunosuppressive tumor, head and neck squamous cell carcinoma (HNSCC) carries a high mutation burden, making immune checkpoint inhibitors promising candidates in this field due to their unique mechanism of action. The present review outlines a comprehensive multidisciplinary cancer treatment approach and elaborates on how combining immunochemotherapy and immunoradiotherapy guidelines could enhance clinical efficacy in patients with HNSCC. Furthermore, the present review explores the immunology of HNSCC, current immunotherapeutic strategies to enhance antitumor activity, ongoing clinical trials and the future direction of the current immune landscape in HNSCC. Advanced-stage HNSCC presents with a poor prognosis, low survival rates and minimal improvement in patient survival trends over time. Understanding the potential of immunotherapy and ways to combine it with surgery, chemotherapy and radiotherapy confers good prospects for the management of human papillomavirus (HPV)-positive HNSCC, as well as other HPV-positive malignancies. Understanding the immune system and its effect on HNSCC progression and metastasis will help to uncover novel biomarkers for the selection of patients and to enhance the efficacy of treatments. Further research on why current immune checkpoint inhibitors and targeted drugs are only effective for some patients in the clinic is needed; therefore, further research is required to improve the overall survival of affected patients.

Elevated Tumor Cell-Intrinsic STING Expression in Advanced Laryngeal Cancer

Laryngeal cancer is the second most common malignancy of the head and neck, worldwide. Immunotherapy targeting checkpoint inhibitors has been approved for the treatment of patients with recurrent or metastatic laryngeal cancer but has a relatively low response rate and outcomes that leave many patients underserved. Targeting the cGAS-STING signaling pathway can potentially improve the activation of immune effector cells, although its role in the development and progression of laryngeal cancer has not yet been investigated in depth. Fifty-nine tumor samples from patients with pathologically confirmed squamous cell carcinoma of the larynx, stage I-IV non-metastatic disease, who were treated at the University Hospital of Split, were immunohistochemically stained for the expression of STING, cGAS, CD8, CD68, and CD163. Elevated tumor cell-intrinsic STING expression was positively associated with stage IV (p = 0.0031), pT3, and pT4 laryngeal cancers (p = 0.0336) as well as with higher histological grades (G2 and G3) (p = 0.0204) and lymph node-positive tumors (p = 0.0371). After adjusting for age, sex, location, and cGAS expression, elevated STING expression was significantly associated with stage IV cancer in a multiple logistic regression model (β = 1.849, SE = ±0.8643, p = 0.0324). Elevated STING expression represents a potentially favorable predictive biomarker for new therapeutic approaches involving STING agonists combined with immunotherapy and DNA-damaging agents (radiotherapy, cisplatin, and PARP inhibitors) in laryngeal cancer.

Tumor-Derived Exosomes and the Role of Liquid Biopsy in Human Papillomavirus Oropharyngeal Squamous Cell Carcinoma

ABSTRACT

The global incidence of human papillomavirus-positive (HPV+) head and neck squamous cell carcinoma (HNSCC) has surged in recent decades, with HPV+ HNSCC accounting for >70% of oropharynx cancers in the United States. Its incidence in men has surpassed that of HPV+ cervical cancer in women, and reliable assays are needed for early detection and to monitor response to therapy. Human papillomavirus-positive OPSCC has a more favorable response to therapy and prognosis than HPV-negative (HPV-) HNSCC, motivating regimens to deintensify curative surgery or chemoradiotherapy protocols. A barrier to deintensifying and personalizing therapy is lack of reliable predictive biomarkers. Furthermore, HPV- HNSCC survival rates are static without reliable surveillance biomarkers available. The emergence of circulating plasma-based biomarkers reflecting the tumor-immune microenvironment heralds a new era in HNSCC diagnosis and therapy. We review evidence on tumor-derived extracellular vesicles (exosomes) as biomarkers for diagnosis, prognostication, and treatment in HPV+ and HPV- HNSCC.

Localized Drug Delivery Systems: An Update on Treatment Options for Head and Neck Squamous Cell Carcinomas

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers in the world, with surgery, radiotherapy, chemotherapy, and immunotherapy being the primary treatment modalities. The treatment for HNSCC has evolved over time, due to which the prognosis has improved drastically. Despite the varied treatment options, major challenges persist. HNSCC chemotherapeutic and immunotherapeutic drugs are usually administered systemically, which could affect the patient's quality of life due to the associated side effects. Moreover, the systemic administration of salivary stimulating agents for the treatment of radiation-induced xerostomia is associated with toxicities. Localized drug delivery systems (LDDS) are gaining importance, as they have the potential to provide non-invasive, patient-friendly alternatives to cancer therapy with reduced dose-limiting toxicities. LDDSs involve directly delivering a drug to the tissue or organ affected by the disease. Some of the common localized routes of administration include the transdermal and transmucosal drug delivery system (DDSs). This review will attempt to explore the different treatment options using LDDSs for the treatment of HNSCC and radiotherapy-induced damage and their potential to provide a better experience for patients, as well as the obstacles that need to be addressed to render them successful.

Concordance between Clinical and Pathological T and N Stages in Polish Patients with Head and Neck Cancers

BACKGROUND

The TNM (tumor, node, metastasis) staging system is important for the successful treatment of head and neck cancers (HNCs). This study aimed to evaluate the concordance between clinical and pathological T and N stages in patients with HNCs in Poland.

METHODS

In this single-center retrospective study, clinical and pathological TNM staging data on 203 patients undergoing surgical treatment for HNC between 2011 and 2018 were collected and compared. The study group was classified as underdiagnosed, overdiagnosed, or correctly diagnosed with HNC based on pathological TNM staging. The concordance between clinical and pathological staging was evaluated using the kappa coefficient.

RESULTS

Clinical and pathological TNM staging showed concordance in 59.9% of patients for primary tumor (T) and in 79.3% of patients for lymph node (N) classifications. Moderate agreement between the clinical and pathological stages was shown for stage T, while substantial agreement was revealed for stage N. The size and extent of the tumor were underestimated or overestimated in 73 of the 182 patients (40.1%), while lymph node involvement was downstaged in 11 of the 53 patients (20.7%).

CONCLUSIONS

The disparities between clinical and pathological staging of HNC demonstrate the need for standardization in physical and pathological examinations, as well as radiographic imaging.

Unique vulnerability of RAC1-mutant melanoma to combined inhibition of CDK9 and immune checkpoints

RAC1P29S is the third most prevalent hotspot mutation in sun-exposed melanoma. RAC1 alterations in cancer are correlated with poor prognosis, resistance to standard chemotherapy, and insensitivity to targeted inhibitors. Although RAC1P29S mutations in melanoma and RAC1 alterations in several other cancers are increasingly evident, the RAC1-driven biological mechanisms contributing to tumorigenesis remain unclear. Lack of rigorous signaling analysis has prevented identification of alternative therapeutic targets for RAC1P29S-harboring melanomas. To investigate the RAC1P29S-driven effect on downstream molecular signaling pathways, we generated an inducible RAC1P29S expression melanocytic cell line and performed RNA-sequencing (RNA-seq) coupled with multiplexed kinase inhibitor beads and mass spectrometry (MIBs/MS) to establish enriched pathways from the genomic to proteomic level. Our proteogenomic analysis identified CDK9 as a potential new and specific target in RAC1P29S-mutant melanoma cells. In vitro, CDK9 inhibition impeded the proliferation of in RAC1P29S-mutant melanoma cells and increased surface expression of PD-L1 and MHC Class I proteins. In vivo, combining CDK9 inhibition with anti-PD-1 immune checkpoint blockade significantly inhibited tumor growth only in melanomas that expressed the RAC1P29S mutation. Collectively, these results establish CDK9 as a novel target in RAC1-driven melanoma that can further sensitize the tumor to anti-PD-1 immunotherapy.

Clinical Significance of PD-L1 Status in Circulating Tumor Cells for Cancer Management during Immunotherapy

The approval of monoclonal antibodies against programmed death-ligand 1 (PD-L1) and programmed cell death protein (PD1) has changed the landscape of cancer treatment. To date, many immune checkpoint inhibitors (ICIs) have been approved by the FDA for the treatment of metastatic cancer as well as locally recurrent advanced cancer. However, immune-related adverse events (irAEs) of ICIs highlight the need for biomarker analysis with strong predictive value. Liquid biopsy is an important tool for clinical oncologists to monitor cancer patients and administer or change appropriate therapy. CTCs frequently express PD-L1, and this constitutes a clinically useful and non-invasive method to assess PD-L1 status in real-time. This review summarizes all the latest findings about the clinical significance of CTC for the management of cancer patients during the administration of immunotherapy and mainly focuses on the assessment of PD-L1 expression in CTCs.

Interplay between EZH2/β-catenin in stemness of cisplatin-resistant HNSCC and their role as therapeutic targets

The Wnt/β-catenin signaling pathway is associated with the regulation of cancer stem cells, and it can be driven by epigenetic modifications. Here, we aim to identify epigenetic modifications involved in the control of the Wnt/β-catenin signaling and investigate the role of this pathway in the accumulation of cancer stem cells (CSC) and chemoresistance of Head and Neck Squamous Cell Carcinoma (HNSCC). Quantitative-PCR, western blot, shRNA assay, viability assay, flow cytometry assay, spheres formation, xenograft model, and chromatin immunoprecipitation were employed to evaluate the Wnt/β-catenin pathway and EZH2 in wild-type and chemoresistant oral carcinoma cell lines, and in the populations of CSC and non-stem cells. We demonstrated that β-catenin and EZH2 were accumulated in cisplatin-resistant and CSC population. The upstream genes of the Wnt/β-catenin signaling (APC and GSK3β) were decreased, and the downstream gene MMP7 was increased in the chemoresistant cell lines. The inhibition of β-catenin and EZH2 combined effectively decreased the CSC population in vitro and reduced the tumor volume and CSC population in vivo. EZH2 inhibition increased APC and GSK3β, and the Wnt/β-catenin inhibition reduced MMP7 levels. In contrast, EZH2 overexpression decreased APC and GSK3β and increased MMP7. EZH2 and β-catenin inhibitors sensitized chemoresistant cells to cisplatin. EZH2 and H3K27me3 bounded the promoter of APC, leading to its repression. These results suggest that EZH2 regulates β-catenin by inhibiting the upstream gene APC contributing to the accumulation of cancer stem cells and chemoresistance. Moreover, the pharmacological inhibition of the Wnt/β-catenin combined with EZH2 can be an effective strategy for treating HNSCC.

Enhancement of Immunotherapies in Head and Neck Cancers Using Biomaterial-Based Treatment Strategies

Head and neck squamous cell carcinoma (HNSCC) is a challenging disease to treat because of typically late-stage diagnoses and tumor formation in difficult-to-treat areas, sensitive to aggressive or invasive treatments. To date, HNSCC treatments have been limited to surgery, radiotherapy, and chemotherapy, which may have significant morbidity and often lead to long-lasting side effects. The development of immunotherapies has revolutionized cancer treatment by providing a promising alternative to standard-of-care therapies. However, single-agent immunotherapy has been only modestly effective in the treatment of various cancers, including HNSCC, with most patients receiving no overall benefit or increased survival. In addition, single-agent immunotherapy's limitations, namely immune-related side effects and the necessity of multidose treatments, must be addressed to further improve treatment efficacy. Biocompatible biomaterials, in combination with cancer immunotherapies, offer numerous advantages in the concentration, localization, and controlled release of drugs, cancer antigens, and immune cells. Biomaterial structures are diverse, and their design can generally be customized to enhance immunotherapy response. In preclinical settings, the use of biomaterials has shown great promise in improving the efficacy of single-agent immunotherapy. Herein, we provide an overview of current immunotherapy treatments for HNSCC and their limitations, as well as the potential applications of biomaterials in enhancing cancer immunotherapies. Impact Statement Advances in anticancer immunotherapies for the past 30 years have yielded exciting clinical results and provided alternatives to long-standing standard-of-care treatments, which are associated with significant toxicities and long-term morbidity. However, patients with head and neck squamous cell carcinoma (HNSCC) have not benefited from immunotherapies as much as patients with other cancers. Immunotherapy limitations include systemic side effects, therapeutic resistance, poor delivery kinetics, and limited patient responses. Biomaterial-enhanced immunotherapies, as explored in this review, are a potentially powerful means of achieving localized drug delivery, sustained and controlled drug release, and immunomodulation. They may overcome current treatment limitations and improve patient outcomes and care.

Role of Surgical Pathologist for Detection of Immunooncologic Predictive Factors in Head and Neck Cancer

Immunotherapy has shown promising results in the treatment of recurrent and metastatic head and neck cancers. Antiprogrammed cell death (PD)-1 therapies have been recently approved in this setting and they are currently tested also in the treatment of locally advanced diseases and in the neoadjuvant setting. However, the clinical benefits of these treatments have been quite variable, hence the need to select those patients who may obtain the maximal efficacy through the identification of predictive biomarkers. Currently, PD-L1 immunohistochemical expression by tumor and immune cells is the most widely used predictive biomarker for immunotherapy in head and neck squamous cell carcinoma. Nevertheless, patients with PD-L1 - tumors may still respond to treatments, thereby emphasizing the need for the identification of other predictive biomarkers. In this review, we summarize the current data on histologic and molecular parameters that can be used to select patients with head and neck cancers for immunotherapy, with a focus on squamous cell carcinoma and salivary gland carcinomas.

Lip Squamous Cell Carcinoma With Spontaneous Eruption and Drainage

A 69-year-old woman with a newly diagnosed T3N2cM0 poorly differentiated squamous cell carcinoma unrelated to human papillomavirus (HPV) of the lower lip mucosa presented to the medical oncology clinic 3 days after initiating neoadjuvant immune checkpoint blockade immunotherapy with redness and swelling of the tumor site. Four days after treatment, a white head formed overlying the tumor that erupted through the skin surface (Figure 1 ). Thin, cloudy discharge that was not foul-smelling drained from the tumor from posttreatment days 5 to 10, at which point the drainage stopped spontaneously. Throughout, the patient reported no pain and remained afebrile. Laboratory results on days 5, 9, and 14 demonstrated the absence of leukocytosis, and serial wound cultures failed to demonstrate pathogenic growth. No antibiotics were administered. The patient completed the neoadjuvant immunotherapy and underwent a margin-negative tumor resection without intraoperative or postoperative complications.

Society for Immunotherapy of Cancer (SITC) consensus definitions for resistance to combinations of immune checkpoint inhibitors with targeted therapies

Immunotherapy offers deep and durable disease control to some patients, but many tumors do not respond to treatment with single-agent immune checkpoint inhibitors (ICIs). One strategy to enhance responses to immunotherapy is via combinations with signal transduction inhibitors, such as antiangiogenic therapies, which not only directly target cancer cells but also could potentially favorably modulate the tumor immune microenvironment. Combination strategies with ICIs have demonstrated enhanced antitumor activity compared with tumor-targeted or antiangiogenic therapy alone in randomized trials in a variety of solid tumor settings, leading to regulatory approval from the US Food and Drug Administration and agencies in other countries for the treatment of endometrial cancer, kidney cancer, melanoma, and hepatocellular carcinoma. Despite improved survival and response rates for some patients when antiangiogenic or targeted therapies are administered with ICIs, many patients continue to progress after combination treatment and urgently need new strategies to address this manifestation of resistance to immunotherapy. Previously, the Society for Immunotherapy of Cancer (SITC) published consensus definitions for resistance to single-agent anti-PD-(L)1. To provide guidance for clinical trial design and to support analyses of emerging molecular and immune profiling data surrounding mechanisms of resistance to ICI-based combinations, SITC convened a follow-up workshop in 2021 to develop consensus definitions for resistance to multiagent ICI combinations. This manuscript reports the consensus clinical definitions for combinations of anti-PD-(L)1 ICIs and targeted therapies. Definitions for resistance to ICIs in combination with chemotherapy and with other ICIs will be published in companion volumes to this paper.

Integrating Immunotherapy into Multimodal Treatment of Head and Neck Cancer

Patients with locally advanced head and neck squamous cell carcinoma (HNSCC) have a poor prognosis, with a significant risk of progression or death despite multimodal treatment with surgery, chemotherapy, and radiotherapy. Immune checkpoint inhibitors targeting the programmed death receptor-1 (PD1) have dramatically changed the treatment landscape for recurrent/metastatic disease, improving overall survival in both the first- and second-line palliative settings. This success has driven the investigation of treatment strategies incorporating immunotherapy earlier into the multimodal curative-intent or salvage treatment of both locally advanced and recurrent/metastatic HNSCC. This review encompassed the following three subjects, with a focus on recently reported and ongoing clinical trials: (1) the use of neoadjuvant immunotherapy prior to surgery for locally advanced HNSCC, (2) the use of immunochemoradiotherapy for locally advanced head and neck cancers, and (3) novel uses of immunotherapy in the salvage of recurrent/metastatic HNSCC via a combined modality, including reirradiation paradigms. The results of these studies are eagerly awaited to improve patient outcomes in this challenging disease.

EGFR pathway targeting drugs in head and neck cancer in the era of immunotherapy

Receptor tyrosine kinases (RTKs) are cell surface receptors that bind growth factor ligands and initiate cellular signaling. Of the 20 classes of RTKs, 7 classes, I-V, VIII, and X, are linked to head and neck cancers (HNCs). We focus on the first class of RTK, epidermal growth factor receptor (EGFR), as it is the most thoroughly studied class. EGFR overexpression is observed in 20% of tumors, and expression of EGFR variant III is seen in 15% of aggressive chemoradiotherapy resistant HNCs. Currently, the EGFR monoclonal antibody (mAb) cetuximab is the only FDA approved RTK-targeting drug for the treatment of HNCs. Clinical trials have also included EGFR mAbs, with tyrosine kinase inhibitors, and small molecule inhibitors targeting the EGFR, MAPK, and mTOR pathways. Additionally, Immunotherapy has been found to be effective in 15 to 20% of patients with recurrent or metastatic HNC as a monotherapy. Thus, attempts are underway for the combinatorial treatment of immunotherapy and EGFR mAbs to determine if the recruitment of immune cells in the tumor microenvironment can overcome EGFR resistance.

Circ_0000052/miR-382-3p axis induces PD-L1 expression and regulates cell proliferation and immune evasion in head and neck squamous cell carcinoma

A better understanding of the mechanisms underlying PD-L1 aberrant expression in head and neck squamous cell carcinoma (HNSCC) will help reveal predictive biomarkers and overcome resistance to treatment. In this study, the prognostic significance of PD-L1 in forty-five HNSCC archival samples was determined by qRT-PCR. The biological function associated with malignant behaviour was assessed by PD-L1 depletion, miR-382-3p re-expression and regulation of circ_0000052. The interactions of PD-L1-miRNA and miRNA-circRNA were determined by qRT-PCR, Western blot analysis, dual-luciferase reporter assays and RNA immunoprecipitation assays. PD-L1 was highly expressed in patient samples and cancer cell lines. Higher levels of PD-L1 were associated with patient recurrences and play a pivotal role in regulating cell proliferation, migration, invasion, clonogenicity and apoptosis. In addition to demonstrating that the IFN-γ/JAK2/STAT1 signalling pathway can induce PD-L1 overexpression in HNSCC, a novel mechanism by which upregulated circ_0000052 mediates PD-L1 overexpression was also demonstrated. To do this, circ_0000052 competitively binds to miR-382-3p and alleviates its repression of PD-L1. This leads to overexpression of PD-L1, causing the aggressiveness of the cells. Our data demonstrate that circ_0000052 is oncogenic, and the circ_0000052/miR-382-3p/PD-L1 axis is critical in HNSCC progression. The manipulation of circRNAs/miRNAs in combination with anti-PD-L1 therapy may improve personalized disease management.

Nonsurgical Treatment Strategies for Elderly Head and Neck Cancer Patients: An Emerging Subject Worldwide

Consistent with the increasing rate of head and neck cancers among elderly adults, there has been an increase in the rate of those receiving nonsurgical treatments to maintain their function and quality of life. However, various problems, such as poor tolerance to chemoradiotherapy-related toxicity, are of greater concern in elderly adults than in younger individuals. In this review, we describe adverse events that should be particularly noted in elderly patients and provide an overview of countermeasures in nonsurgical treatments. We mainly focus on cisplatin-based chemoradiotherapy-the primary treatment for head and neck squamous cell carcinoma (HNSCC). Furthermore, we review the molecular targeted drugs and immune checkpoint inhibitors for elderly patients with HNSCC. Although the number of older patients is increasing worldwide, clinical trials aimed at determining the standard of care typically enroll younger or well-conditioned elderly patients. There is still very little evidence for treating elderly HNSCC older patients, and the question of optimal treatment needs to be explored.

Implications and Emerging Therapeutic Avenues of Inflammatory Response in HPV+ Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinomas (HNSCC) are a heterogeneous group of malignancies which have shown exponential incidence in the last two decades especially due to human papillomavirus (HPV) infection. The HPV family comprises more than 100 types of viruses with HPV16 and HPV18 being the most prevalent strains in HNSCC. Literature data reveal that the mutation profile as well as the response to chemotherapy and radiotherapy are distinct among HPV+ versus HPV-negative tumors. Furthermore, the presence of the virus induces activation of an immune response, in particular the recruitment of specific antiviral T lymphocytes to tumor sites. These T cells when activated produce soluble factors including cytokines and chemokines capable of modifying the local immune tumor microenvironment and impact on tumor response to the treatment. In this comprehensive review we investigated current knowledge on how the presence of an HPV can modify the inflammatory response systemically and within the tumor microenvironment's immunological responses, thereby impacting on disease prognosis and survival. We highlighted the research gaps and emerging approaches necessary to discover novel immunotherapeutic targets for HPV-associated HNSCC.

Electroporation in Head-and-Neck Cancer: An Innovative Approach with Immunotherapy and Nanotechnology Combination

Squamous cell carcinoma is the most common malignancy that arises in the head-and-neck district. Traditional treatment could be insufficient in case of recurrent and/or metastatic cancers; for this reason, more selective and enhanced treatments are in evaluation in preclinical and clinical trials to increase in situ concentration of chemotherapy drugs promoting a selectively antineoplastic activity. Among all cancer treatment types (i.e., surgery, chemotherapy, radiotherapy), electroporation (EP) has emerged as a safe, less invasive, and effective approach for cancer treatment. Reversible EP, using an intensive electric stimulus (i.e., 1000 V/cm) applied for a short time (i.e., 100 μs), determines a localized electric field that temporarily permealizes the tumor cell membranes while maintaining high cell viability, promoting cytoplasm cell uptake of antineoplastic agents such as bleomycin and cisplatin (electrochemotherapy), calcium (Ca²⁺ electroporation), siRNA and plasmid DNA (gene electroporation). The higher intracellular concentration of antineoplastic agents enhances the antineoplastic activity and promotes controlled tumor cell death (apoptosis). As secondary effects, localized EP (i) reduces the capillary blood flow in tumor tissue ("vascular lock"), lowering drug washout, and (ii) stimulates the immune system acting against cancer cells. After years of preclinical development, electrochemotherapy (ECT), in combination with bleomycin or cisplatin, is currently one of the most effective treatments used for cutaneous metastases and primary skin and mucosal cancers that are not amenable to surgery. To reach this clinical evidence, in vitro and in vivo models were preclinically developed for evaluating the efficacy and safety of ECT on different tumor cell lines and animal models to optimize dose and administration routes of drugs, duration, and intensity of the electric field. Improvements in reversible EP efficacy are under evaluation for HNSCC treatment, where the focus is on the development of a combination treatment between EP-enhanced nanotechnology and immunotherapy strategies.

Case report: Patient specific combination of surgery and immunotherapy in advanced squamous cell carcinoma of the head and neck - a case series and review of literature

BACKGROUND

Prognosis of patients with recurrent or metastatic head and neck cancer is generally poor. Adjuvant immunotherapy (IT) featuring immune checkpoint inhibition (ICI) is standard of care in advanced stage head and neck squamous cell carcinoma (HNSCC) and cutaneous squamous cell carcinoma (CSCC). ICI response rates in CSCC are described as higher than in HNSCC. IT is constantly shifting into earlier disease stages which confronts the surgeon with immunotherapeutically pre-treated patients. It is therefore becoming increasingly difficult to assess which patients with symptomatic tumor disease and a lack of curative surgical option might benefit from salvage surgery.

CASE PRESENTATIONS

The following 6 cases describe therapeutic decision-making regarding ICI and (salvage) surgery in patients with advanced stage HNSCC or CSCC. Cases A and B focus on neoadjuvant ICI followed by salvage surgery. In Cases C and D salvage surgery was performed after short-term stabilization with partial response to ICI. The last two cases (Cases E and F) address the surgical approach after failure of ICI. All cases are discussed in the context of the current study landscape and with focus on individual decision-making. For better understanding, a timetable of the clinical course is given for each case.

CONCLUSIONS

ICI is rapidly expanding its frontiers into the neoadjuvant setting, frequently confronting the surgeon with heavily pretreated patients. Salvage surgery is a viable therapeutic concept despite the rise of systemic treatment options. Decision-making on surgical intervention in case of a salvage surgery remains an individual choice. For neoadjuvant ICI monitoring regarding pathological tumor response or tumor necrosis rate, we suggest correlation between the initial biopsy and the definite tumor resectate in order to increase its significance as a surrogate marker. Scheduling of neoadjuvant ICI should be further investigated, as recent studies indicate better outcomes with shorter time frames.

The role of T-cells in head and neck squamous cell carcinoma: From immunity to immunotherapy

Head and neck squamous cell carcinoma (HNSCC) encompass a group of complex entities of tumours affecting the aerodigestive upper tract. The main risk factors are strongly related to tobacco and alcohol consumption, but also HPV infection is often associated. Surgery, radiotherapy and/or chemotherapy are the standard treatments, though the 5-year overall survival is less than 50%. The advances in genomics, molecular medicine, immunology, and nanotechnology have shed a light on tumour biology which helps clinical researchers to obtain more efficacious and less toxic therapies. Head and neck tumours possess different immune escape mechanisms including diminishing the immune response through modulating immune checkpoints, in addition to the recruitment and differentiation of suppressive immune cells. The insights into the HNSCC biology and its strong interaction with the tumour microenvironment highlights the role of immunomodulating agents. Recently, the knowledge of the immunological features of these tumours has paved the way for the discovery of effective biomarkers that allow a better selection of patients with odds of improving overall survival through immunotherapy. Specially biomarkers regarding immune checkpoint inhibitors antibodies, such as anti-PD-1/PD-L1 and anti-CTLA-4 in combination with standard therapy or as monotherapy. New immunotherapies to treat head and neck cancer carcinomas, such as CAR T cells and nanoparticles have been the center of attention and in this review, we discuss the necessity of finding targets for the T cell in the cancer cells to generate CAR T cells, but also the relevance of evaluating specificity and safety of those therapies.