Neoadjuvant immunotherapy in head and neck cancer: Rationale, current evidence and future perspective

A Phase II Open-Label Randomized Clinical Trial of Preoperative Durvalumab or Durvalumab plus Tremelimumab in Resectable Head and Neck Squamous Cell Carcinoma

PURPOSE

Clinical implications of neoadjuvant immunotherapy in patients with locally advanced but resectable head and neck squamous cell carcinoma (HNSCC) remain largely unexplored.

PATIENTS AND METHODS

Patients with resectable HNSCC were randomized to receive a single dose of preoperative durvalumab (D) with or without tremelimumab (T) before resection, followed by postoperative (chemo)radiotherapy based on multidisciplinary discretion and 1-year D treatment. Artificial intelligence (AI)-powered spatial distribution analysis of tumor-infiltrating lymphocytes and high-dimensional profiling of circulating immune cells tracked dynamic intratumoral and systemic immune responses.

RESULTS

Of the 48 patients enrolled (D, 24 patients; D+T, 24 patients), 45 underwent surgical resection per protocol (D, 21 patients; D+T, 24 patients). D±T had a favorable safety profile and did not delay surgery. Distant recurrence-free survival (DRFS) was significantly better in patients treated with D+T than in those treated with D monotherapy. AI-powered whole-slide image analysis demonstrated that D+T significantly reshaped the tumor microenvironment toward immune-inflamed phenotypes, in contrast with the D monotherapy or cytotoxic chemotherapy. High-dimensional profiling of circulating immune cells revealed a significant expansion of T-cell subsets characterized by proliferation and activation in response to D+T therapy, which was rare following D monotherapy. Importantly, expansion of specific clusters in CD8+ T cells and non-regulatory CD4+ T cells with activation and exhaustion programs was associated with prolonged DRFS in patients treated with D+T.

CONCLUSIONS

Preoperative D±T is feasible and may benefit patients with resectable HNSCC. Distinct changes in the tumor microenvironment and circulating immune cells were induced by each treatment regimen, warranting further investigation.

Neoadjuvant chemoimmunotherapy shows major pathological response and low recurrence in head and neck squamous cell carcinoma

BACKGROUND

The study aimed to investigate the efficacy and survival outcomes of neoadjuvant chemotherapy combined with programmed cell death protein 1 (PD-1) blockade (neoadjuvant chemoimmunotherapy) for patients with resectable head and neck squamous cell carcinoma (HNSCC).

METHODS

A retrospective analysis was conducted. Patients with initially diagnosed, resectable HNSCCs who received the neoadjuvant chemoimmunotherapy and radical surgery were included. Correlation analysis between patients' clinical characteristics and pathological responses, and survival analysis were performed.

RESULTS

A total of 79 patients were included. The majority of patients (55, 69.6%) were diagnosed at locally advanced stages and most of them (58, 73.4%) had tumor located at the oral cavity. Nearly half of patients (35, 44.3%) received two cycles of neoadjuvant chemoimmunotherapy and the rest had three or more cycles. The R0 resection rate was 98.7%. In the pathological evaluation, 53.1% of patients reached pathological complete responses or major pathological responses. After a median follow-up of 17.0 months, the 1-year disease-free survival (DFS) and overall survival (OS) rates were 87.2% and 97.4%, respectively. The pathological response showed a significantly positive association with survival benefits (p < 0.001). Patients with human papillomavirus (HPV)-positive oropharyngeal cancer had the best pathological response and survival outcomes. Besides, history of radiation at head and neck region and poor pathological response were found to be independent risk factors of DFS for patients receiving such treatments.

CONCLUSION

Neoadjuvant chemoimmunotherapy of HNSCC showed high rate of pathological response and low recurrence rate, holding promise for becoming the new standard of care for resectable HNSCC.

Neoadjuvant immune checkpoint blockade enhances local and systemic tumor immunity in head and neck cancer

PURPOSE OF REVIEW

Neoadjuvant (presurgical) immune checkpoint blockade (ICB) has shown promising clinical activity in head and neck cancer and other cancers, including FDA approvals for neoadjuvant approaches for triple-negative breast cancer and nonsmall cell lung cancer. Here we will review recent data from clinical trials in head and neck squamous cell carcinoma (HNSCC), including mechanistic studies highlighting local and systemic effects on T cell-mediated immunity.

RECENT FINDINGS

A series of clinical trials of neoadjuvant ICB have documented evidence of clinical activity, including clinical to pathologic downstaging and pathologic response in a subset of patients. Also, emerging data suggest improved survival outcomes for patients with tumors responsive to neoadjuvant ICB. In depth mechanistic studies have documented intra-tumoral expansion of CD8 T cell populations characterized by tissue residency and cytotoxicity programs. Treatment also leads to expansion of activated CD8 T cells in the blood, many of which share TCR sequences with tumor-infiltrating T cells. The frequency of activated circulating CD8 T cell populations is correlated with the degree of pathologic response within tumors.

SUMMARY

Even a short duration of neoadjuvant immunotherapy can enhance local and systemic tumor-reactive T cell populations. Downstaging induced by neoadjuvant ICB can reduce the extent of surgical resection in this anatomically sensitive location.

Immunotherapy for head and neck squamous cell carcinoma: current status and perspectives

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several solid cancers, including head and neck squamous cell carcinoma (HNSCC). First approved for second-line settings, ICIs are now used for the first-line treatment of HNSCCs, mainly in combination with standard chemotherapy. This review focuses on the results of the main phase III studies evaluating ICIs in recurrent or metastatic HNSCCs. The efficacy and indications according to the PD-L1 status, the main predictive biomarker, are discussed. The results of trials assessing ICI efficacy for locally advanced disease, including the neoadjuvant setting are also discussed. Finally, therapeutic combinations that are potential treatments for HNSCCs, including ICIs and targeted therapies such as anti-EGFR agents, are presented.

Association between spatial distribution of leukocyte subsets and clinical presentation of head and neck squamous cell carcinoma

Background

Interactions between tumor cells and cells in the microenvironment contribute to tumor development and metastasis. The spatial arrangement of individual cells in relation to each other influences the likelihood of whether and how these cells interact with each other.

Methods

This study investigated the effect of spatial distribution on the function of leukocyte subsets in the microenvironment of human head and neck squamous cell carcinoma (HNSCC) using multiplex immunohistochemistry (IHC). Leukocyte subsets were further classified based on analysis of two previously published HNSCC single-cell RNA datasets and flow cytometry (FC).

Results

IHC revealed distinct distribution patterns of leukocytes differentiated by CD68 and CD163. While CD68hiCD163lo and CD68hiCD163hi cells accumulated near tumor sites, CD68loCD163hi cells were more evenly distributed in the tumor stroma. PD-L1hi and PD-1hi cells accumulated predominantly around tumor sites. High cell density of PD-L1hi CD68hiCD163hi cells or PD-1hi T cells near the tumor site correlated with improved survival. FC and single cell RNA revealed high variability within the CD68/CD163 subsets. CD68hiCD163lo and CD68hiCD163hi cells were predominantly macrophages (MΦ), whereas CD68loCD163hi cells appeared to be predominantly dendritic cells (DCs). Differentiation based on CD64, CD80, CD163, and CD206 revealed that TAM in HNSCC occupy a broad spectrum within the classical M1/M2 polarization. Notably, the MΦ subsets expressed predominantly CD206 and little CD80. The opposite was observed in the DC subsets.

Conclusion

The distribution patterns and their distinct interactions via the PD-L1/PD-1 pathway suggest divergent roles of CD68/CD163 subsets in the HNSCC microenvironment. PD-L1/PD-1 interactions appear to occur primarily between specific cell types close to the tumor site. Whether PD-L1/PD-1 interactions have a positive or negative impact on patient survival appears to depend on both the spatial localization and the entity of the interacting cells. Co-expression of other markers, particularly CD80 and CD206, supports the hypothesis that CD68/CD163 IHC subsets have distinct functions. These results highlight the association between spatial leukocyte distribution patterns and the clinical presentation of HNSCC.

Neoadjuvant use of oncolytic herpes virus G47Δ prevents local recurrence after insufficient resection in tongue cancer models

A complete resection of tongue cancer is often difficult. We investigate the usefulness of administering G47Δ (teserpaturev), a triple-mutated oncolytic herpes simplex virus type 1, prior to resection. G47Δ exhibits good cytopathic effects and replication capabilities in all head and neck cancer cell lines tested. In an orthotopic SCCVII tongue cancer model of C3H/He mice, an intratumoral inoculation with G47Δ significantly prolongs the survival. Further, mice with orthotopic tongue cancer received neoadjuvant G47Δ (or mock) therapy with or without "hemilateral" resection, the maximum extent avoiding surgical deaths. Neoadjuvant G47Δ and resection led to 10/10 survival (120 days), whereas the survivals for G47Δ alone and resection alone were 6/10 and 5/10, respectively: all control animals died by day 11. Furthermore, 100% survival was achieved with neoadjuvant G47Δ therapy even when the resection area was narrowed to "partial," providing insufficient resection margins, whereas hemilateral resection alone caused death by local recurrence in half of the animals. G47Δ therapy caused increased number of tumor-infiltrating CD8+ and CD4+ cells, increased F4/80+ cells within the residual tongues, and increased expression of immune-related genes in and around the tumor. These results imply that neoadjuvant use of G47Δ is useful for preventing local recurrence after tongue cancer surgery.

Epidemiology, Risk Factors, and Prevention of Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is a group of malignancies, involving the oral cavity, pharynx, hypopharynx, larynx, nasal cavity, and salivary glands, that together compose the seventh most common cancer diagnosis worldwide. With 890,000 new cases and 450,000 deaths annually per GLOBOCAN estimates, HNSCC accounts for roughly 4.5% of cancer diagnoses and deaths. In the developing world, the incidence of HNSCC is growing with increasing consumption of tobacco (smoked or chewed), alcohol, and areca nut (betel quid). Alcohol and tobacco have a synergistic effect, with the heavy consumption of both increasing HNSCC risk 40-fold. In developed nations, HPV-related HNSCC surpasses tobacco- and alcohol-related disease. HPV-related HNSCC more commonly affects the oropharynx, hypopharynx, and larynx than the oral cavity, and is associated with a significantly longer median survival (130 months vs. 20 months). Discrepancies in etiology as well as disparities in lifestyle choices and access to healthcare may account for the greater incidence and poorer survival of HNSCC among minority and lower-socioeconomic-status communities in developed nations. Pharmacotherapy and counseling together have been shown to be effective in promoting smoking and alcohol cessation. Education on cancer risk and community engagement have reduced areca nut consumption in Asia as well as in diaspora communities. HPV vaccination, starting at age 11-12 for both sexes, has been shown to reduce the prevalence of high-risk HPV serologies and prevent pre-cancerous lesions of the cervix, vagina, and vulva. As of 2020, 58.6% of eligible adolescents in the US have received the full two-vaccine series. Increased adoption of vaccination, education on safe sex practices, and routine visual oral screening for high-risk patients would curb growing HNSCC incidence in developed nations.

Durable complete remission with local therapies after neoadjuvant and adjuvant nivolumab in recurrent/metastatic head and neck cancer

Up to 10-15% of patients with first-line recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) present with platinum-refractory disease. The anti-PD1 nivolumab is the first therapeutic option in this setting achieving a 19.2% objective response rate and a 7.7-month median overall survival (OS). Given the poor prognosis of platinum-refractory patients, those showing slow progressive disease with no functional status deterioration should maintain nivolumab beyond progression in the absence of severe or unmanageable toxicities. Another strategy is to use local therapies such as radiotherapy and surgical tumor resection in cases of oligometastatic or oligoprogressive disease. Both strategies may significantly improve disease control and OS in these populations. We present the case of a patient with platinum-refractory disease treated with first-line nivolumab beyond progression who achieved a durable complete response after palliative radiation and surgical resection of five tumor lesions. To our knowledge, this is the first reported case of an R/M HNSCC treated with such a strategy outside a clinical trial and contributes to the evidence for combining anti-PD1 agents and local therapies in selected patients with R/M HNSCC.

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.

Clinical Response to Neoadjuvant Immunotherapy Combined with Targeted Therapy and Chemotherapy in Oral Squamous Cell Carcinoma: Experience in Three Patients

Immune checkpoint inhibitors (ICIs) pembrolizumab and nivolumab have been approved for the treatment of head and neck squamous cell carcinoma (HNSCC) and used in neoadjuvant immunotherapy in clinical trials. However, combination of ICIs with targeted therapy and chemotherapy was rarely used in pre-surgical HNSCC patients. Herein, we encountered three cases of patients with oral squamous cell carcinoma (OSCC) who all had good responses to neoadjuvant immunotherapy (anti-PD-1 inhibitors) combined with nimotuzumab (anti-EGFR monoclonal antibody) plus paclitaxel. Both Case 1 and Case 2 underwent the same neoadjuvant therapeutic combination (nivolumab, nimotuzumab and paclitaxel) and exhibited a marked tumor shrinkage even complete disappearance by radiological evaluation. Moreover, pathological response was observed in post-surgical tissues of Case 1. Additionally, Case 3 with tongue squamous cell carcinoma also had satisfactory tumor regression (complete healing of his tongue ulcer upon treatment) after receiving similar neoadjuvant therapy with sintilimab (another PD-1 inhibitor), nimotuzumab and paclitaxel. We characterized their potential causes behind favorable treatment outcomes. While there were differences in driver mutations and tumor mutation burden (TMB) identified in pre-treatment tumor tissues among the three patients, numerous CD68+ (macrophages) infiltrates were common for all the cases. Of note, the majority (>80%) of the total macrophages were molecularly defined as PD-L1-positive macrophages. Given the high expression of PD-L1 in macrophages is associated with better immunotherapy outcomes, we propose that the high proportion of CD68+PD-L1+ cells in total macrophages alone could serve as a promising biomarker for neoadjuvant immunotherapy in combination with other therapies in HNSCC.

Head and Neck Squamous Cell Carcinoma in Elderly Patients: Role of Radiotherapy and Chemotherapy

Simple Summary

The focus of this review deals with the management of elderly patients with head and neck squamous cell carcinoma, discussing the role of clinical management, geriatric evaluation and therapeutic approaches (radiation therapy and systemic therapies).

Abstract

Head and neck squamous cell carcinomas (HNSCC) constitute the sixth most common malignancy worldwide, with approximately 25–40% of the diagnosed patients older than 70 years. HNSCC patients are often frail and frequently have multiple comorbidities due to their unhealthy lifestyle, and evidence suggests that older patients may receive less aggressive and suboptimal treatment than younger patients with the same disease status. The aim of this review is to depict and summarize the evidence regarding the different strategies that can be used in the clinical management of elderly HNSCC patients. Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used. This paper contains a narrative report and a critical discussion of clinical approaches in the context of elderly HNSCC.