Nivolumab versus standard, single-agent therapy of investigator's choice in recurrent or metastatic squamous cell carcinoma of the head and neck (CheckMate 141): health-related quality-of-life results from a randomised, phase 3 trial

Paclitaxel for second-line treatment of squamous cell carcinoma of the head and neck: A multicenter retrospective Italian study

BACKGROUND

Squamous cell carcinoma of the head and neck (SCCHN) accounts for 3% of all malignant tumors in Italy. Immune checkpoint inhibitors combined with chemotherapy is first-line treatment for SCCHN; however, second-line treatment options are limited. Taxanes are widely used for combination therapy of SCCHN, as clinical trials have shown their efficacy in patients with this disease, particularly in patients with prior therapy.

AIM

To perform a multicenter retrospective study on the efficacy and safety of weekly paclitaxel for SCCHN.

METHODS

All patients were previously treated with at least one systemic therapy regimen, which included platinum-based therapy in the vast majority. No patient received prior immunotherapy.

RESULTS

Median progression-free survival (mPFS) was 3.4 months and median overall survival (mOS) was 6.5 months. Subgroup analysis was performed according to three principal prognostic factors: Smoking, alcohol consumption, and body mass index. Analysis demonstrated reduced survival, both mOS and mPFS, in the unfavorable prognostic groups, with the biggest deltas observed in mOS.

CONCLUSION

Weekly paclitaxel provided favorable survival and disease control rates, with low severe adverse events. Paclitaxel is a safe and valid therapeutic option for patients with SCCHN who received prior therapy.

Comparison of PD-L1 assays in head and neck carcinoma

Programmed cell death-ligand 1 (PD-L1) expression is a predictive biomarker for response to immune checkpoint inhibitor in head and neck squamous cell carcinoma. Given the range of antibodies and platforms for PD-L1 testing, it is essential to understand the performance of different staining and scoring methods. PD-L1 expression in 156 head and neck mucosal squamous cell carcinoma (HNmSCC) cases at Asan Medical Center was assessed using 106 tissue microarray (TMA) cores and 50 whole slides. Three standardised PD-L1 assays (22C3 pharmDx, SP263, and 28-8 pharmDx) and one laboratory-developed test (22C3 LDT) were evaluated: the combined positive score (CPS) with ≥1, ≥20, and ≥50 cut-offs, and the tumour positive score (TPS) with ≥1%, ≥20%, ≥50% cut-offs. Concordance on a continuous scale among the assays was good to excellent for CPS [intraclass correlation coefficient (ICC) range 0.73-0.94] and TPS (ICC range 0.70-0.94) and in both TMA and whole slides cohorts. Stratification by variable cut-offs demonstrated moderate to good agreement among most assays, as analysed by Gwet's AC1. PD-L1 expression was significantly correlated with tumour location using the 22C3 pharmDx assay (CPS, p=0.014; TPS, p=0.033). Notable concordance was found among PD-L1 assays, suggesting their potential interchangeability in HNmSCC.

Anti-PD-(L)1-Based Neoadjuvant Therapy in Head and Neck Carcinoma: a Meta-analysis of Prospective Clinical Trials

OBJECTIVE

This meta-analysis aims to evaluate the efficacy and safety of antiprogressive disease (PD)-(L)1-based neoadjuvant therapy in head and neck squamous cell carcinoma (HNSCC) patients and identify potential prognostic biomarkers.

DATA SOURCES

Databases were systematically searched for prospective clinical trials evaluating the efficacy and safety of anti-PD-(L)1-based neoadjuvant therapy for HNSCC before January 12, 2024.

REVIEW METHODS

We estimated the efficacy and safety of neoadjuvant immune checkpoint inhibitors. Subgroup and sensitivity analyses were further performed.

RESULTS

A total of 570 patients from 20 studies were included. The pooled major pathological response (MPR), pathological complete response (pCR), and partial pathological response (PPR) rates were 30.7%, 15.3%, and 68.2%, respectively. Surgical complications, surgical delayed rate, all grade treatment-related adverse effects (TRAEs) and ≥Grade 3 TRAEs were 0.6%, 0.3%, 82.6%, and 9.7%, respectively. Best MPR or pCR rate was detected in patients receiving neoadjuvant anti-PD-(L)1 therapy + radiotherapy (with MPR rate of 75.5% and pCR rate of 51.1%) and neoadjuvant anti-PD-(L)1 therapy + chemotherapy groups (with MPR rate of 57.5% and pCR rate of 26.7%). No differences were detected in subgroups stratified by neoadjuvant treatment cycles, human papillomavirus (HPV) status, and tumor location. Patients with baseline Combined Positive Score (CPS) ≥ 20 have higher MPR and pCR rates compared to patients with CPS < 20. High Tumor Cell Proportion Score was also associated with MPR and pCR. Objective response rate is a strong predictor of MPR (odds ratio [OR] = 7.78, 95% confidence interval [CI] = 3.20%-18.91%) and pCR (OR = 3.24, 95% CI = 1.40%-7.48%).

CONCLUSION

Anti-PD-(L)1-based neoadjuvant therapy was effective and safe for HNSCC patients.

Impact of immune-related adverse events on survival among patients with head-and-neck squamous cell carcinoma

Aim: Immune-checkpoint inhibitors (ICIs) have revolutionized treatment of metastatic head and neck squamous cell carcinomas (HNSCCs). Our goal was to assess for an association between immune-related adverse events (irAEs) and clinical outcomes for patients on ICIs.Methods: We analyzed a cohort of 110 HNSCC patients who received ICI therapy at the University of Virginia.Results: On review, 48% of our patients experienced an irAE with the most common events being hypothyroidism (30%), dermatitis (14%) and hepatitis (11%). Women were more likely to experience irAEs. Treatment interruption/discontinuation occurred in 43% patients with irAEs. Development of irAEs was associated with superior objective response rate (68 vs. 39%, p = 0.009), with a greater rate of CR (17 vs. 5%) and PR (32 vs. 16%). Twelve patients underwent ICI re-treatment following irAE, with 17% attaining a complete disease response, 25% attaining a partial response, 33% achieving stable disease and 25% experiencing disease progression with ICI resumption.Conclusion: Development of irAE was associated with superior objective response rate, with a greater rate of CR and PR. ICI re-treatment following irAE was feasible in a significant proportion of patients and can be attempted in carefully selected patients, given the dearth of second-line therapies for these patients.

The branched N-glycan of PD-L1 predicts immunotherapy responses in patients with recurrent/metastatic HNSCC

Immunotherapy has revolutionized cancer treatment, but the lack of a reliable predictive biomarker for treatment response remains a challenge. Alpha-1,6-Mannosylglycoprotein 6-β-N-Acetylglucosaminyltransferase 5 (MGAT5) is a key regulator of complex N-glycan synthesis, and its dysregulation is associated with cancer progression. The lectin Phaseolus vulgaris leukoagglutinin (PHA-L) specifically binds to mature MGAT5 products. Previous studies have indicated elevated PHA-L staining in head and neck squamous cell carcinoma (HNSCC), which implies increased activity of MGAT5. However, the specific role of MGAT5 in HNSCC remains unclear. In this study, we found significantly higher PHA-L staining and MGAT5 expression in HNSCC tumors compared to adjacent non-tumor tissues. Using a mass spectrometry (MS)-based glycoproteomic approach, we identified 163 potential protein substrates of MGAT5. Functional analysis revealed that protein substrates of MGAT5 regulated pathways related to T cell proliferation and activation. We further discovered that PD-L1 was among the protein substrates of MGAT5, and the expression of MGAT5 protected tumor cells from cytotoxic T lymphocyte (CTL) killing. Treatment of nivolumab alleviated the protective effects of MGAT5 on CTL activity. Consistently, patients with MGAT5-positive tumors showed improved responses to immunotherapy compared to those with MGAT5-negative tumors. Using purified PD-L1 from HNSCC cells and a glycoproteomic approach, we further deciphered that the N35 and N200 sites carry the majority of complex N-glycans on PD-L1. Our findings highlight the critical role of MGAT5-mediated branched N-glycans on PD-L1 in modulating the interaction with the immune checkpoint receptor PD-1. Consequently, we propose that MGAT5 could serve as a biomarker to predict patients' responses to anti-PD-1 therapy. Furthermore, targeting the branched N-glycans at N35 and N200 of PD-L1 may lead to the development of novel diagnostic and therapeutic approaches.

PD-L1 immunohistochemical expression considering HPV status in oropharyngeal squamous cell carcinoma

This systematic review aims to determine whether the presence of human papillomavirus (HPV) influences the immunohistochemical expression of programmed cell death-1 ligand (PD-L1) in oropharyngeal squamous cell carcinoma (OPSCC). PD-L1 immunohistochemical expression varies in OPSCC, and the presence of HPV is a plausible explanation for this variability. Comprehending these findings is crucial, as high PD-L1 expression in the tumor microenvironment of OPSCC can help identify patient subgroups that could be suitable for immunotherapy. Therefore, a systematic review was conducted following PRISMA guidelines (CRD42023437800). An electronic literature search was performed without time or language restrictions. The search included PubMed/MEDLINE, Embase, Scopus, Web of Science, https://clinictrials.gov, and relevant journals. A meta-analysis was performed using RStudio. Fourteen studies involving 1,629 participants were included. The sample consisted predominantly of males (81.26%) with a mean age of 58.3 years. Concerning clinical and pathological characteristics, the most frequently described anatomical location was the tonsils (68.54%), and most participants were either current or former smokers (78%) and alcohol users (79%). Advanced TNM IV was the most common stage. Regarding histopathological characteristics, HPV 16 was the only type mentioned, and half of the cases were detected through immunohistochemistry. The SP142 clone (35.7%) and the pattern of membrane immunostaining in tumor cells (71%) were the most commonly employed methods. The most prevalent findings were positive expression of PD-L1 (64.28%) and negative HPV status (57.14%). The association between PD-L1 positivity and HPV positivity (78.57%) was confirmed by meta-analysis. The conclusion was that HPV-positive status has an impact on immunohistochemical expression of PD-L1 in OPSCC.

Comparison of Tumor Microenvironments between Primary Tumors and Lymph Node Metastases in Head and Neck Squamous Cell Carcinoma and Their Predictive Role in Immune Checkpoint Inhibitor Treatment

The relationship between tumor microenvironments (TMEs) of regional lymph node metastases (LNMs) and primary tumors in head and neck squamous cell carcinoma (HNSCC) remains unclear. This study compared tumor-infiltrating lymphocytes (TILs) and the immune phenotype (IP), characterized by spatial TIL distribution, between primary tumors and LNMs. Twenty-one HNSCC patients with regional LNM who received immune checkpoint inhibitors (ICIs) were included. A paired comparative analysis of TIL densities and IP between primary tumors and LNMs revealed no significant difference or correlation between TIL densities in primary tumors and LNMs. Their IPs were discordant in 12 patients (57.1%). Patients with high intratumoral TIL exhibited longer progression-free survival (PFS) than those with low intratumoral TIL in both primary tumors (median, 5.2 vs. 1.3 months, p = 0.003) and LNMs (median, 30.2 vs. 1.3 months, p = 0.012). Patients with inflamed IP exhibited longer PFS than those with non-inflamed IP in both primary tumors (median, 4.5 vs. 1.3 months, p = 0.043) and LNMs (median, 4.1 vs. 1.3 months, p = 0.037). Given the lack of correlation in TIL densities, the discrepancies in IP, and the predictive value of both TMEs, evaluating the TMEs of both primary tumors and LNMs may be beneficial for the precise use of ICIs in HNSCC. There was a significant discordance between the TME of primary tumors and LNMs, with implications in survival outcomes. Therefore, evaluating the TME of both the primary tumor and LNM could be beneficial for the precise use of ICIs in HNSCC.

Effects of tislelizumab on health-related quality of life in patients with recurrent or metastatic nasopharyngeal cancer

BACKGROUND

This study evaluated health-related quality of life (HRQoL) in the RATIONALE-309 (NCT03924986) intent-to-treat (ITT) population and in a subgroup of patients with liver metastases.

METHODS

Patients were randomized 1:1 to tislelizumab + chemotherapy or placebo + chemotherapy. As the secondary endpoint, HRQoL was evaluated using seven selected scores from the EORTC QLQ-C30 and QLQ Head and Neck Cancer module (QLQ-H&N35).

RESULTS

Of 263 randomized patients in the ITT population (tislelizumab + chemotherapy n = 131, placebo + chemotherapy n = 132), 43% had liver metastases (tislelizumab + chemotherapy n = 56; placebo + chemotherapy n = 57). No differences in change in selected scores on the QLQ-C30 from baseline to cycle 4 or cycle 8 were observed for the ITT or liver metastases subgroup. No differences in selected QLQ-H&N35 scores were observed between the arms from baseline to cycle 4. In the ITT population and the liver metastases subgroup, a greater reduction from baseline to cycle 8 was observed in the tislelizumab + chemotherapy arm than the placebo + chemotherapy arm in QLQ-H&N35 pain score. At cycle 8 in the liver metastases subgroup, the tislelizumab + chemotherapy arm experienced greater improvement in the QLQ-H&N35 senses problems score than the placebo + chemotherapy arm. Differences in time to deterioration between arms were not observed.

CONCLUSIONS

The current findings, along with improved survival and favorable safety, suggests that tislelizumab + chemotherapy represents a potential first-line treatment for recurrent or metastatic nasopharyngeal cancer.

Locoregional therapies combined with immune checkpoint inhibitors for liver metastases

Immune checkpoint inhibitors (ICIs) have achieved remarkable success in clinical research and practice. Notably, liver metastasis is not sensitive to ICIs. Liver locoregional therapies can cause irreversible damage to tumor cells and release tumor antigens, thereby providing a rationale for immunotherapy treatments in liver metastasis. The combination therapy of ICIs with locoregional therapies is a promising option for patients with liver metastasis. Preclinical studies have demonstrated that combining ICIs with locoregional therapies produces a significantly synergistic anti-tumor effect. However, the current evidence for the efficacy of ICIs combined with locoregional therapies remains insufficient. Therefore, we review the literature on the mechanisms of locoregional therapies in treating liver metastasis and the clinical research progress of their combination with ICIs.

Prolonged in-use physicochemical and biological stability of nivolumab and pembrolizumab diluted in saline infusion bags and in partially used medication vials

AIM/BACKGROUND

The aim of this study was to determine long-term physicochemical and biological stability of nivolumab and pembrolizumab diluted in saline infusion bags and partially used medication vials. This may enable the prolonged clinical use of these expensive monoclonal antibodies (mAbs) to minimize the economic loss.

METHODS

Sterile nivolumab and pembrolizumab concentrates in partially used medication vials and compounded nivolumab and pembrolizumab infusion solutions were stored for two and four weeks, respectively, at 2-8°C in the dark. Subsequently, concentrates and compounded solutions were stored for an additional two weeks under ambient temperature and light conditions. A panel of validated and complementary methods, consisting of enzyme-linked immunosorbent assay, size exclusion chromatography, and dynamic light scattering, were used to assess the biological and physiochemical stability of these mAbs.

RESULTS

All samples showed that purity and concentration had remained within the criteria of <5% as stated in the European Pharmacopoeia. Diluted in infusion bags, nivolumab and pembrolizumab remained biologically and physiochemically stable for up to four weeks when stored at 2-8°C in the dark with an additional two weeks of ambient temperature and light. Stability in partially used medication vials was demonstrated for at least two weeks when stored at 2-8°C in the dark with an additional two weeks of ambient temperature and light.

CONCLUSION

The findings of this study justify the storage and clinical re-use of sterile nivolumab and pembrolizumab in partially used medication vials and compounded IV infusion bags for up to six weeks. This minimizes the risk of economic loss due to waste. Moreover, these findings support the batch-wise compounding of fixed-dose and dose-banded nivolumab and pembrolizumab infusion bags.

Deciphering the interplay of HPV infection, MHC-II expression, and CXCL13+ CD4+ T cell activation in oropharyngeal cancer: implications for immunotherapy

BACKGROUND

Human papillomavirus (HPV) infection has become an important etiological driver of oropharyngeal squamous cell carcinoma (OPSCC), leading to unique tumor characteristics. However, the interplay between HPV-associated tumor cells and tumor microenvironment (TME) remains an enigma.

METHODS

We performed a single-cell RNA-sequencing (scRNA-seq) on HPV-positive (HPV+) and HPV-negative (HPV‒) OPSCC tumors, each for three samples, and one normal tonsil tissue. Ex vivo validation assays including immunofluorescence staining, cell line co-culture, and flow cytometry analysis were used to test specific subtypes of HPV+ tumor cells and their communications with T cells.

RESULTS

Through a comprehensive single-cell transcriptome analysis, we uncover the distinct transcriptional signatures between HPV+ and HPV‒ OPSCC. Specifically, HPV+ OPSCC tumor cells manifest an enhanced interferon response and elevated expression of the major histocompatibility complex II (MHC-II), potentially bolstering tumor recognition and immune response. Furthermore, we identify a CXCL13+CD4+ T cell subset that exhibits dual features of both follicular and pro-inflammatory helper T cells. Noteworthily, HPV+ OPSCC tumor cells embrace extensive intercellular communications with CXCL13+CD4+ T cells. Interaction with HPV+ OPSCC tumor cells amplifies CXCL13 and IFNγ release in CD4+T cells, fostering a pro-inflammatory TME. Additionally, HPV+ tumor cells expressing high MHC-II and CXCL13+CD4+ T cell prevalence are indicative of favorable overall survival rates in OPSCC patients.

CONCLUSIONS

Together, our study underscores a synergistic inflammatory immune response orchestrated by highly immunogenic tumor cells and CXCL13+CD4+ T cells in HPV+ OPSCC, offering useful insights into strategy development for patient stratification and effective immunotherapy in OPSCC.

Treatment of elderly patients with head and neck cancer in an aging society: Focus on geriatric assessment and surgical treatment

Previous studies of the treatment of elderly head and neck cancer (HNC) patients were very limited and sometimes controversial. Although conclusions differ across various reports, it is often concluded that advanced chronological age does not directly affect prognosis, but that comorbidities and declines in physical and cognitive functions promote the occurrence of adverse events, especially with surgical treatment. Geriatric assessment (GA) and its screening tools are keys to help us understand overall health status and problems, predict life expectancy and treatment tolerance, and to influence treatment choices and interventions to improve treatment compliance. In addition, personal beliefs and values play a large role in determining policies for HNC treatment for elderly patients, and a multidisciplinary approach is important to support this. In this review, past research on HNC in older adults is presented, and the current evidence is explained, focusing on the management of elderly HNC patients, with an emphasis on the existing reports on each treatment stage and modality, especially the surgical procedures.

Single-cell transcriptome dissecting the microenvironment remodeled by PD1 blockade combined with photodynamic therapy in a mouse model of oral carcinogenesis

Oral squamous cell carcinoma (OSCC) stands as a predominant and perilous malignant neoplasm globally, with the majority of cases originating from oral potential malignant disorders (OPMDs). Despite this, effective strategies to impede the progression of OPMDs to OSCC remain elusive. In this study, we established mouse models of oral carcinogenesis via 4-nitroquinoline 1-oxide induction, mirroring the sequential transformation from normal oral mucosa to OPMDs, culminating in OSCC development. By intervening during the OPMDs stage, we observed that combining PD1 blockade with photodynamic therapy (PDT) significantly mitigated oral carcinogenesis progression. Single-cell transcriptomic sequencing unveiled microenvironmental dysregulation occurring predominantly from OPMDs to OSCC stages, fostering a tumor-promoting milieu characterized by increased Treg proportion, heightened S100A8 expression, and decreased Fib_Igfbp5 (a specific fibroblast subtype) proportion, among others. Notably, intervening with PD1 blockade and PDT during the OPMDs stage hindered the formation of the tumor-promoting microenvironment, resulting in decreased Treg proportion, reduced S100A8 expression, and increased Fib_Igfbp5 proportion. Moreover, combination therapy elicited a more robust treatment-associated immune response compared with monotherapy. In essence, our findings present a novel strategy for curtailing the progression of oral carcinogenesis.

Assessment of endpoint definitions in recurrent and metastatic mucosal head and neck squamous cell carcinoma trials: Head and Neck Cancer International Group consensus recommendations

Transparent and precise endpoint definitions are a crucial aspect of clinical trial conduct and reporting, and are used to communicate the benefit of an intervention. Previous studies have identified inconsistencies in endpoint definitions across oncological clinical trials. Here, the Head and Neck Cancer International Group assessed endpoint definitions from phase 3 trials or trials considered practice-changing for patients with recurrent or metastatic mucosal head and neck squamous cell carcinoma, published between 2008 and 2021. We identify considerable and global heterogeneity in endpoint definitions, which undermines the interpretation of results and development of future studies. We show how fundamental components of even incontrovertible endpoints such as overall survival vary widely, highlighting an urgent need for increased rigour in reporting and harmonisation of endpoints.

Tumor Is Not the Only Target: Ensuring Equitable Person-Centered Supportive Care in the Era of Precision Medicine

Communication in oncology has always been challenging. The new era of precision oncology creates prognostic uncertainty. Still, person-centered care requires attention to people and their care needs. Living with cancer portends an experience that is life-altering, no matter what the outcome. Supporting patients and families through this unique experience requires careful attention, honed skills, an understanding of process and balance measures of innovation, and recognizing that supportive care is a foundational element of cancer medicine, rather than an either-or approach, an and-with approach that emphasizes the regular integration of palliative care (PC), geriatric oncology, and skilled communication.

DKK2 promotes the progression of oral squamous cell carcinoma through the PI3K/AKT signaling pathway

OBJECTIVE

This study aimed to investigate the impact of Dickkopf 2 (DKK2) on the progression of oral squamous cell carcinoma (OSCC) and explore its role in the PI3K/AKT signaling transduction pathway.

MATERIALS AND METHODS

The study initially examined the expression of the DKK2 gene in OSCC tissues and normal tissues. Simultaneously, the expression of DKK2 in HOK cells and OSCC cells was verified, and changes in DKK2 expression under hypoxic conditions were detected. DKK2 overexpression and knockdown were performed in SCC-15 and CAL-27 cells. Subsequently, the effects of DKK2 on the proliferation, migration and invasion of OSCC were detected. Western blotting was employed to detect the expression of key proteins in the DKK2/PI3K/AKT signaling axis before and after transfection, and further explore the relevant molecular mechanisms.

RESULTS

Compared to normal tissues, DKK2 expression was elevated in OSCC tissues. The expression of DKK2 in the SCC-15 and CAL-27 cell lines was higher than that in HOK cells, and hypoxic conditions could promote DKK2 expression. DKK2 overexpression promoted cell proliferation, migration, and invasion, while DKK2 knockdown inhibited these processes. DKK2 overexpression activated the PI3K/AKT pathway, while DKK2 knockdown suppressed this pathway.

CONCLUSION

This study suggests that hypoxic conditions enhance the expression of DKK2 in OSCC. DKK2 regulates the proliferation, migration, and invasion of OSCC through the PI3K/AKT signaling pathway.

Neoadjuvant immunotherapy for head and neck squamous cell carcinoma

The neoadjuvant immunotherapy approach marks a significant shift in the treatment paradigm of potentially curable HNSCC. Here, current therapies, despite being highly individualized and advanced, often fall short in achieving satisfactory long-term survival rates and are frequently associated with substantial morbidity.The primary advantage of this approach lies in its potential to intensify and enhance treatment regimens, offering a distinct modality that complements the existing triad of surgery, radiotherapy, and chemotherapy. Checkpoint inhibitors have been at the forefront of this evolution. Demonstrating moderate yet significant survival benefits in the recurrent-metastatic setting with a relatively better safety profile compared to conventional treatments, these agents hold promise when considered for earlier stages of HNSCC.On the other hand, a significant potential benefit of introducing immunotherapy in the neoadjuvant phase is the possibility of treatment de-escalation. By reducing the tumor burden before surgery, this strategy could lead to less invasive surgical interventions. The prospect of organ-sparing protocols becomes a realistic and highly valued goal in this context. Further, the early application of immunotherapy might catalyze a more effective and durable immune response. The induction of an immune memory may potentially lead to a more effective surveillance of residual disease, decreasing the rates of local, regional, and distant recurrences, thereby enhancing overall and recurrence-free survival.However, neoadjuvant immunotherapy is not without its challenges. One of the primary concerns is the safety and adverse events profile. While data suggest that adverse events are relatively rare and manageable, the long-term safety profile in the neoadjuvant setting, especially in the context of curative intent, remains a subject for ongoing research. Another unsolved issue lies in the accurate assessment of treatment response. The discrepancy between radiographic assessment using RECIST criteria and histological findings has been noted, indicating a gap in current imaging techniques' ability to accurately reflect the true efficacy of immunotherapy. This gap underscores the necessity for improved imaging methodologies and the development of new radiologic and pathologic criteria tailored to evaluate the response to immunotherapy accurately.Treatment combinations and timing represent another layer of complexity. There is a vast array of possibilities in combining immunotherapy agents with conventional chemotherapy, targeted therapy, radiation, and other experimental treatments. Determining the optimal treatment regimen for individual patients becomes an intricate task, especially when comparing small, single-arm, non-randomized trials with varying regimens and outcome measures.Moreover, one needs to consider the importance of pre- and intraoperative decision-making in the context of neoadjuvant immunotherapy. As experience with this treatment paradigm grows, there is potential for more tailored surgical approaches based on the patient's remaining disease post-neoadjuvant treatment. This consideration is particularly relevant in extensive surgeries, where organ-sparing protocols could be evaluated.In practical terms, the multi-modal nature of this treatment strategy introduces complexities, especially outside clinical trial settings. Patients face challenges in navigating the treatment landscape, which involves coordination across multiple medical disciplines, highlighting the necessity for streamlined care pathways at specialized centers to facilitate effective treatment management if the neoadjuvant approach is introduced to the real-world.These potential harms and open questions underscore the critical need for meticulously designed clinical trials and correlational studies to ensure patient safety and efficacy. Only these can ensure that this new treatment approach is introduced in a safe way and fulfils the promise it theoretically holds.

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.

Nivolumab in unresectable advanced, recurrent or metastatic esophageal squamous cell carcinoma

Esophageal cancer (EC) is the eighth most common cancer worldwide. In view of biology and anatomical restrictions, multimodality treatment strategies have been developed for EC. However, the prognosis of patients with advanced EC remains especially poor. Immunotherapy, such as PD-1/PD-L1 and CTLA-4/B7 blockade, has emerged as a potent treatment for many types of cancer and has been approved in many countries. Based on the results of the ATTRACTION-3 trial, nivolumab, an anti-PD-1 monoclonal antibody, was approved by the US FDA for patients with platinum-resistant, unresectable, recurrent or metastatic esophageal squamous cell carcinoma. The CheckMate 648 trial demonstrated that the combination of nivolumab with platinum-based fluoropyrimidine chemotherapy and combination immunotherapy with nivolumab and ipilimumab, an anti-CTLA-4 monoclonal antibody, showed a survival benefit in patients with advanced esophageal squamous cell carcinoma compared with doublet chemotherapy. This review focuses on nivolumab-containing treatments for patients with advanced esophageal squamous cell carcinoma.

BPIFB1, Serving as a Downstream Effector of EBV-miR-BART4, Blocks Immune Escape of Nasopharyngeal Carcinoma via Inhibiting PD-L1 Expression

Nasopharyngeal carcinoma (NPC) is one of the most common tumors of head and neck in the Southeast Asia. PD-L1-dependent immune escape plays a critical role involved in NPC development. BPIFB1 has previously reported to take tumor-suppressive actions on NPC cell proliferation and migration. Nonetheless, the function of BPIFB1 in immune escape remains largely elusive. Expression pattern on mRNA and protein levels of target genes in NPC patients' samples and cell lines were examined by qRT-PCR, western blot, and immunohistochemistry staining, respectively. The assessment of CD8+ T-cell apoptosis and expression was determined by flow cytometry. Molecular interactions were verified using chromatin immunoprecipitation (ChIP) and luciferase reporter assay. BPIFB1 was downregulated in NPC tumor tissues, exhibiting a negative correlation of PD-L1. Overexpression of BPIFB1 significantly inhibited the expression of PD-L1, suppressing the apoptosis and enhancing the expression of CD8+ T cells. Mechanistically, BPIFB1 was found to repress the expression of STAT1, which was identified to be an upstream activator of PD-L1. Furthermore, the EBV-encoded miR-BART4 overexpressed in NPC cells could directly target and inhibit BPIFB1. This study provided a comprehensive understanding of the molecular mechanism for the upstream and downstream pathway of BPIFB1 related with immune escape, indicating a novel approach for the treatment of NPC.

Neoadjuvant chemo-immunotherapy with camrelizumab plus nab-paclitaxel and cisplatin in resectable locally advanced squamous cell carcinoma of the head and neck: a pilot phase II trial

Neoadjuvant chemoimmunotherapy has emerged as a potential treatment option for resectable head and neck squamous cell carcinoma (HNSCC). In this single-arm phase II trial (NCT04826679), patients with resectable locally advanced HNSCC (T2‒T4, N0‒N3b, M0) received neoadjuvant chemoimmunotherapy with camrelizumab (200 mg), nab-paclitaxel (260 mg/m2), and cisplatin (60 mg/m2) intravenously on day one of each three-week cycle for three cycles. The primary endpoint was the objective response rate (ORR). Secondary endpoints included pathologic complete response (pCR), major pathologic response (MPR), two-year progression-free survival rate, two-year overall survival rate, and toxicities. Here, we report the perioperative outcomes; survival outcomes were not mature at the time of data analysis. Between April 19, 2021 and March 17, 2022, 48 patients were enrolled and received neoadjuvant therapy, 27 of whom proceeded to surgical resection and remaining 21 received non-surgical therapy. The ORR was 89.6% (95% CI: 80.9, 98.2) among 48 patients who completed neoadjuvant therapy. Of the 27 patients who underwent surgery, 17 (63.0%, 95% CI: 44.7, 81.2) achieved a MPR or pCR, with a pCR rate of 55.6% (95% CI: 36.8, 74.3). Treatment-related adverse events of grade 3 or 4 occurred in two patients. This study meets the primary endpoint showing potential efficacy of neoadjuvant camrelizumab plus nab-paclitaxel and cisplatin, with an acceptable safety profile, in patients with resectable locally advanced HNSCC.

The Use of Immune Regulation in Treating Head and Neck Squamous Cell Carcinoma (HNSCC)

Immunotherapy has emerged as a promising new treatment modality for head and neck cancer, offering the potential for targeted and effective cancer management. Squamous cell carcinomas pose significant challenges due to their aggressive nature and limited treatment options. Conventional therapies such as surgery, radiation, and chemotherapy often have limited success rates and can have significant side effects. Immunotherapy harnesses the power of the immune system to recognize and eliminate cancer cells, and thus represents a novel approach with the potential to improve patient outcomes. In the management of head and neck squamous cell carcinoma (HNSCC), important contributions are made by immunotherapies, including adaptive cell therapy (ACT) and immune checkpoint inhibitor therapy. In this review, we are focusing on the latter. Immune checkpoint inhibitors target proteins such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) to enhance the immune response against cancer cells. The CTLA-4 inhibitors, such as ipilimumab and tremelimumab, have been approved for early-stage clinical trials and have shown promising outcomes in terms of tumor regression and durable responses in patients with advanced HNSCC. Thus, immune checkpoint inhibitor therapy holds promise in overcoming the limitations of conventional therapies. However, further research is needed to optimize treatment regimens, identify predictive biomarkers, and overcome potential resistance mechanisms. With ongoing advancements in immunotherapy, the future holds great potential for transforming the landscape of oral tumor treatment and providing new hope for patients.

Neoplasia-related and treatment-induced lymphopenia: impact on the outcome of chemoradiotherapy in laryngeal cancer

INTRODUCTION

The role of the immune system in the efficacy of radiotherapy (RT) has been well established. We examined the role of neoplasia-related and treatment-induced lymphopenia in the outcome of RT or chemoradiotherapy (CRT) in squamous cell laryngeal cancer.

MATERIALS AND METHODS

We retrospectively analyzed a series of 135 laryngeal carcinomas treated with radical or postoperative RT/CRT. Six lymphocyte-related variables were defined and examined: i. lymphocyte counts (LCs) before a brief course of induction chemotherapy, ii. pre-RT LCs, iii. post-RT LCs, iv. pre-RT neutrophil/lymphocyte ratio (N/L), v. pre-RT monocyte/lymphocyte ratio (M/L), and vi. pre-RT platelet/lymphocyte ratio (Pt/L).

RESULTS

RT and CRT resulted in a significant decrease of LCs at the end of therapy, and this was significantly more prominent in patients treated with radical intent and neck irradiation (median LC nadir 810/μl vs. 1250/μl; p = .0003). Induction chemotherapy did not intensify the lymphotoxic effect of RT. LCs lower than the 33rd percentile before RT (<1718/μl) and after RT (<720/μl) were significantly linked to poor locoregional progression-free survival (LRFS; p = .02 and p = .08, respectively) and disease-specific overall survival (OS; p = .02 and p = .03, respectively). This was also confirmed multivariate analysis (LRFS: p = .006/HR = 2.41 and p = .08/HR = 1.76, respectively; OS: p = .001/HR = 3.06 and p = .02/HR = 2.07, respectively). High pre-RT N/L, M/L, and Pt/L ratios were also of ominous prognostic relevance.

CONCLUSIONS

Both neoplasia-related and RT-induced lymphopenia define the outcome of RT in terms of locoregional failure, incidence of metastasis, and, finally, disease-specific survival of patients with laryngeal cancer. Restoration of pre-RT lymphopenia and protection of peripheral lymphocytes during RT emerge as critical issues that demand therapeutic interventions to maximize the efficacy of RT/CRT in patients with laryngeal cancer.

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.

Mechanisms of Resistance and Therapeutic Perspectives in Immunotherapy for Advanced Head and Neck Cancers

Immunotherapy is emerging as an effective treatment for advanced head and neck cancers and interest in this treatment modality has led to rapid expansion of this research. Pembrolizumab and nivolumab, monoclonal antibodies directed against the programmed cell death-1 (PD-1) receptor, are US Food and Drug Administration (FDA)- and European Medical Agency (EMA)-approved immunotherapies for head and neck squamous cell carcinoma (HNSCC). Resistance to immunotherapy is common, with about 60% of patients with recurrent or metastatic HNSCC not responding to immunotherapy and only 20-30% of patients without disease progression in the long term. Overcoming resistance to immunotherapy is therefore essential for augmenting the effectiveness of immunotherapy in HNSCC. This review details the innate and adaptive mechanisms by which head and neck cancers can become resistant to immunotherapeutic agents, biomarkers that can be used for immunotherapy patient selection, as well as other factors of the tumor microenvironment correlated with therapeutic response and prognosis. Numerous combinations and novel immunotherapies are currently being trialed, based on better understood immune evasion mechanisms. These potential treatments hold the promise of overcoming resistance to immunotherapy in head and neck cancers.

Personalized Treatment of Recurrent, Metastatic Head and Neck Cancer Guided by Patient-Derived Xenograft Models

Recurrent or metastatic head and neck squamous cell carcinoma (RMHNSCC) is associated with a poor prognosis and short survival duration. There is an urgent need to identify personalized predictors of drug response to guide the selection of the most effective therapy for each individual recurrence. We tested the feasibility of patient-derived xenografts (PDX) for guiding their RMHNSCC salvage treatment. Fresh tumor samples from eligible, consented patients were implanted into mice. Established tumors were expanded in mouse PDX cohorts to identify responses to candidate salvage drug treatments in parallel testing. Patients alive and suitable for chemotherapy were treated based on responses determined by PDX testing. Nine patient tumors were successfully engrafted in mice with an average time of 89.2±41.7 days. Four patients' PDX models underwent parallel drug testing. Two patients received PDX-guided therapy. In one of these patients, single agents of cetuximab and paclitaxel demonstrated the best responses in the PDX model, and this patient exhibited sequential partial responses to each drug, including a 17-month clinical response to cetuximab. The main limitation of PDX testing for RMHNSCC was the time delay in obtaining testing results. Despite this, parallel PDX testing may be feasible for a subset of patients and appears to correlate with clinical benefit.

Targeting MDM2 in malignancies is a promising strategy for overcoming resistance to anticancer immunotherapy

MDM2 has been established as a biomarker indicating poor prognosis for individuals undergoing immune checkpoint inhibitor (ICI) treatment for different malignancies by various pancancer studies. Specifically, patients who have MDM2 amplification are vulnerable to the development of hyperprogressive disease (HPD) following anticancer immunotherapy, resulting in marked deleterious effects on survival rates. The mechanism of MDM2 involves its role as an oncogene during the development of malignancy, and MDM2 can promote both metastasis and tumor cell proliferation, which indirectly leads to disease progression. Moreover, MDM2 is vitally involved in modifying the tumor immune microenvironment (TIME) as well as in influencing immune cells, eventually facilitating immune evasion and tolerance. Encouragingly, various MDM2 inhibitors have exhibited efficacy in relieving the TIME suppression caused by MDM2. These results demonstrate the prospects for breakthroughs in combination therapy using MDM2 inhibitors and anticancer immunotherapy.

Induction Toripalimab and Chemotherapy for Organ Preservation in Locally Advanced Laryngeal and Hypopharyngeal Cancer: A Single-Arm Phase II Clinical Trial

PURPOSE

The aim of this study was to assess the efficacy, toxicities, and potential role of larynx preservation of induction chemotherapy combined with programmed cell death protein 1 (PD-1) inhibitor in locally advanced laryngeal and hypopharyngeal cancer.

PATIENTS AND METHODS

This is a single-arm phase II study. Patients with histopathologically confirmed, resectable locally advanced laryngeal/hypopharyngeal squamous cell carcinoma and Eastern Cooperative Oncology Group Performance Status 0-1 were eligible. Three cycles of induction chemotherapy (paclitaxel 175 mg/m2 d1, cisplatin 25 mg/m2 d1-3) combined with PD-1 inhibitor (toripalimab 240 mg d0) were administered. Response assessment was performed after induction chemoimmunotherapy using RECIST 1.1 criteria. Patients with a complete/partial response of the primary tumor received concurrent chemoradiation, followed by maintenance therapy of toripalimab. Otherwise, patients were referred to surgery, followed by adjuvant (chemo) radiation and maintenance therapy of toripalimab. The primary endpoint is a larynx preservation rate at 3 months postradiation.

RESULTS

Twenty-seven patients were enrolled. Most cases exhibited stage IV disease (81.5%), with T4 representing 37.0%. Five patients underwent pretreatment tracheostomy because of impaired larynx function. Overall response rate of induction chemoimmunotherapy was 85.2%. At 3 months postradiation, the larynx preservation rate was 88.9%. With a median follow-up of 18.7 months, the 1-year overall survival rate, progression-free survival rate, and larynx preservation rate were 84.7%, 77.6%, and 88.7%, respectively. When excluding those with pretreatment tracheostomy, the 1-year larynx preservation rate was 95.5%. Exploratory analysis revealed that relapse correlated with enrichment of RNA signature of hypoxia and M2 macrophage-associated genes.

CONCLUSIONS

Induction toripalimab combined with chemotherapy provided encouraging activity, promising larynx preservation rate and acceptable toxicity in this cohort of extensively locally advanced laryngeal and hypopharyngeal cancer.

Multimodality treatment in recurrent/metastatic squamous cell carcinoma of head and neck: current therapy, challenges, and future perspectives

Squamous cell carcinoma of the head and neck is a complex group of diseases that presents a challenge to the clinician. The prognosis in the recurrent/metastatic disease is particularly dismal, with a median survival of approximately 12 months. Recently, the personalized and multimodal approach has increased prognosis by integrating locoregional strategies (salvage surgery and stereotactic radiotherapy) and systemic treatments (chemotherapy, immunotherapy, and target therapy). Malnutrition is a significant clinical problem that interferes with dose intensity, and thus, feeding supplementation is critical not only to increase the quality of life but also to improve overall survival. With this review, we want to emphasize the importance of the multidisciplinary approach, quality of life, and nutritional supportive care and to integrate the latest updates of predictive biomarkers for immunotherapy and future therapeutic strategies.

Selective Treatment Deintensification by Reducing Radiation Dose and Omitting Concurrent Chemotherapy Based on Response to Induction Chemotherapy in Human Papillomavirus-Associated Oropharyngeal Squamous Cell Carcinoma: A Single-Arm, Phase 2 Trial (IChoice-01)

PURPOSE

To demonstrate the feasibility of deintensification regimen in the light of the response to induction chemotherapy (IC) in human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC).

METHODS AND MATERIALS

Patients with p16+ OPSCC, T1-2/N1-3M0 (excluding T1N1M0 with single and ≤3 cm lymph node) or T3-4N0-3M0 were enrolled between January 2019 and July 2021. All patients received 2 cycles of IC with docetaxel 75 mg/m2 dL and cisplatin 75 mg/m2 dL every 3 weeks. Those with major responses (≥50% decrease in both primary and lymph nodes) to IC entered the deintensification cohort (cohort D), in which intensity modulated radiation therapy alone was given to a reduced dose of 60 Gy/30 fractions. Those who failed to meet major responsesentered the concurrent chemoradiotherapy cohort (cohort C), where the dose was simultaneously integrated boosted to a standard 70 Gy/35 fractions to nonmajor response sites, concurrently with cisplatin 80 mg/m2 dL,22. Patient-reported swallow function was documented using the MD Anderson Dysphagia Inventory. The primary endpoint was 2-year progression-free survival (PFS) using Simon's 2 stage design.

RESULTS

A total of 26 of 48 (54.2%) participants met the criteria to enter cohort D and 22 of 48 (45.8%) patients entered cohort C. With a median follow-up time of 29.7 months (6.9-48.0 months), 2-year PFS and OS rates were 85.4% and 93.6%, respectively for all enrolled patients. In cohort D, 2-year PFS and OS rates were both 100%. Grade 3 and 4 IC-related toxicities included leukopenia/neutropenia occurring in 41.7% and hyponatremia in 4.2% of patients. A higher incidence of grade 3 and 4 mucositis (61.9% vs 23.1% P = .022) was observed in cohort C. Consistent decline in longitudinal MD Anderson Dysphagia Inventory scores were observed at month 3 after radiation therapy between cohorts and both were found to recover to baseline at month 12.

CONCLUSIONS

Selective radiation therapy dose reduction and concurrent chemotherapy removal based on IC response in HPV + OPSCC was feasible and promising. Further study of this strategy to balance efficacy and toxicity is warranted in a prospective controlled trial.

Health-Related Quality of Life With Nivolumab Plus Chemotherapy Versus Chemotherapy in Patients With Advanced Gastric/Gastroesophageal Junction Cancer or Esophageal Adenocarcinoma From CheckMate 649

PURPOSE

In CheckMate 649, first-line nivolumab plus chemotherapy prolonged overall survival versus chemotherapy in patients with advanced/metastatic non-human epidermal growth factor receptor 2 (HER2)-positive gastric/gastroesophageal junction cancer (GC/GEJC) or esophageal adenocarcinoma (EAC). We present exploratory patient-reported outcomes (PROs).

METHODS

In patients (N = 1,581) concurrently randomly assigned 1:1 to nivolumab plus chemotherapy or chemotherapy and in those with tumor PD-L1 expression at a combined positive score (CPS) of ≥5, health-related quality of life (HRQoL) was assessed using the EQ-5D and Functional Assessment of Cancer Therapy-Gastric (FACT-Ga), which included the FACT-General (FACT-G) and Gastric Cancer subscale (GaCS). The FACT-G GP5 item assessed treatment-related symptom burden. Longitudinal changes in HRQoL were assessed using mixed models for repeated measures in the PRO analysis population (randomly assigned patients with baseline and ≥1 postbaseline assessments). Time to symptom or definitive deterioration analyses were also conducted.

RESULTS

In the PRO analysis population (n = 1,360), PRO questionnaire completion rates were mostly >80% during treatment. Patient-reported symptom burden was not increased with nivolumab plus chemotherapy versus chemotherapy. Mean improved changes from baseline were greater with nivolumab plus chemotherapy versus chemotherapy for FACT-Ga total, GaCS, and EQ-5D visual analog scale in patients with a CPS of ≥5; results were similar for the overall PRO analysis population. In CPS ≥5 and all randomly assigned populations, nivolumab plus chemotherapy reduced the risk of symptom deterioration versus chemotherapy, on the basis of FACT-Ga total score and GaCS; time to definitive deterioration was longer, and the risk of definitive deterioration in HRQoL was reduced with nivolumab plus chemotherapy across EQ-5D and most FACT-Ga measures (hazard ratio [95% CI] <1).

CONCLUSION

Compared with chemotherapy alone, first-line nivolumab plus chemotherapy showed stable or better on-treatment HRQoL in patients with advanced/metastatic non-HER2-positive GC/GEJC/EAC and also showed decreased risk of definitive HRQoL deterioration.

Dynamic Up-Regulation of PD-L1 in the Progression of Oral Squamous Cell Carcinoma

The introduction of immune checkpoint inhibition for recurrent and metastatic head and neck cancer has brought a new treatment option for patients suffering from advanced oral cancers without a chance for curation using surgery or radiotherapy. The application of immune checkpoint inhibitors in most cases is based on the expression levels of PD-L1 in the tumor tissue. To date, there is a lack of data on the dynamic regulation of PD-L1 during disease progression. Therefore, this study aimed to evaluate the expression levels of PD-L1 in a large cohort of patients (n = 222) with oral squamous cell carcinoma including primary and recurrent tumors. Semiautomatic digital pathology scoring was used for the assessment of PD-L1 expression levels in primary and recurrent oral squamous cell carcinoma. Survival analysis was performed to evaluate the prognostic significance of the protein expression at different stages of the disease. We found a significant up-regulation of PD-L1 expression from primary disease to recurrent tumors (mean PD-L1 H-scores: primary tumors: 47.1 ± 31.4; recurrent tumors: 103.5 ± 62.8, p < 0.001). In several cases, a shift from low PD-L1 expression in primary tumors to high PD-L1 expression in recurrent tumors was identified. Multivariate Cox regression analysis did not reveal a significantly higher risk of death (p = 0.078) or recurrence (p = 0.926) in patients with higher PD-L1 expression. Our findings indicate that the exclusive analysis of primary tumor tissue prior to the application of checkpoint blockade may lead to the misjudgment of PD-L1 expression in recurrent tumors.

Multidimensional biomarker predicts disease control in response to immunotherapy in recurrent or metastatic head and neck squamous-cell carcinoma

PURPOSE

Anti-PD-1 therapy provides clinical benefit in 40-50% of patients with relapsed and/or metastatic head and neck squamous cell carcinoma (RM-HNSCC). Selection of anti- PD-1 therapy is typically based on patient PD-L1 immunohistochemistry (IHC) which has low specificity for predicting disease control. Therefore, there is a critical need for a clinical biomarker that will predict clinical benefit to anti-PD-1 treatment with high specificity.

METHODS

Clinical treatment and outcomes data for 103 RM-HNSCC patients were paired with RNA-sequencing data from formalin-fixed patient samples. Using logistic regression methods, we developed a novel biomarker classifier based on expression patterns in the tumor immune microenvironment to predict disease control with monotherapy PD-1 inhibitors (pembrolizumab and nivolumab). The performance of the biomarker was internally validated using out-of-bag methods.

RESULTS

The biomarker significantly predicted disease control (65% in predicted non-progressors vs. 17% in predicted progressors, p < 0.001) and was significantly correlated with overall survival (OS; p = 0.004). In addition, the biomarker outperformed PD-L1 IHC across numerous metrics including sensitivity (0.79 vs 0.64, respectively; p = 0.005) and specificity (0.70 vs 0.61, respectively; p = 0.009).

CONCLUSION

This novel assay uses tumor immune microenvironment expression data to predict disease control and OS with high sensitivity and specificity in patients with RM-HNSCC treated with anti-PD-1 monotherapy.

Targeting the Immunoglobulin IGSF9 Enhances Antitumor T-cell Activity and Sensitivity to Anti-PD-1 Immunotherapy

Immune checkpoints modulate the immune response and represent important immunotherapy targets for cancer treatment. However, as many tumors are resistant to current immune checkpoint inhibitors, the discovery of novel immune checkpoints could facilitate the development of additional immunotherapeutic strategies to improve patient responses. Here, we identified increased expression of the adhesion molecule immunoglobulin superfamily member 9 (IGSF9) in tumor cells and tumor-infiltrating immune cells across multiple cancer types. IGSF9 overexpression or knockout in tumor cells did not alter cell proliferation in vitro or tumor growth in immunocompromised mice. Alternatively, IGSF9 deficient tumor cells lost the ability to suppress T-cell proliferation and exhibited reduced growth in immunocompetent mice. Similarly, growth of tumor cells was reduced in IGSF9 knockout syngeneic and humanized mice, accompanied by increased tumor-infiltrating T cells. Mechanistically, the extracellular domain (ECD) of IGSF9 bound to T cells and inhibited their proliferation and activation, and the tumor-promoting effect of IGSF9 ECD was reversed by CD3+ T-cell depletion. Anti-IGSF9 antibody treatment inhibited tumor growth and enhanced the antitumor efficacy of anti-programmed cell death protein 1 immunotherapy. Single-cell RNA sequencing revealed tumor microenvironment remodeling from tumor promoting to tumor suppressive following anti-IGSF9 treatment. Together, these results indicate that IGSF9 promotes tumor immune evasion and is a candidate immune checkpoint target.

SIGNIFICANCE

IGSF9 is an immune checkpoint regulator that suppresses T-cell activation in cancer and can be targeted to stimulate antitumor immunity and inhibit tumor growth.

Evolving role of novel radiosensitizers and immune checkpoint inhibitors in (chemo)radiotherapy of locally advanced head and neck squamous cell carcinoma

Chemoradiotherapy (CRT) remains the standard treatment for locally advanced head and neck squamous cell carcinoma (LA-HNSCC), based on numerous randomized controlled trials and meta-analyses demonstrating that CRT improved locoregional control and overall survival. Achieving locoregional control is a crucial outcome for the treatment of HNSCC, as it directly affects patient quality of life and survival. Cisplatin is the recommended standard-of-care radiosensitizing agent for LA-HNSCC patients undergoing CRT, whereas cetuximab-radiotherapy is reserved for cisplatin-ineligible patients. Immune checkpoint inhibitors (ICIs) have shown promise in the treatment of recurrent or metastatic HNSCC. However, the combination of ICIs with standard-of-care radiotherapy or chemoradiotherapy in LA-HNSCC has not demonstrated significant improvement in survivals. Over the past few decades, significant advancements in radiotherapy techniques have allowed for more precise and effective radiation delivery while minimizing toxicity to surrounding normal tissues. These advances have led to improved treatment outcomes and quality of life for patients with LA-HNSCC. Despite these advancements, the development of novel radiosensitizing agents remains an unmet need. This review discusses the mechanism of radiotherapy and its impact on the immune system. We summarize the latest clinical development of novel radiosensitizing agents, such as SMAC mimetics, DDR pathway inhibitors, and CDK4/6 inhibitor. We also elucidate the emerging evidence of combining ICIs with radiotherapy or chemoradiotherapy in curative settings for LA-HNSCC, using both concurrent and sequential approaches. Lastly, we discuss the future direction of systemic therapy in combination with radiotherapy in treatment for LA-HNSCC.

Labdane and ent-halimane diterpenoids with STAT3-inhibitory activity from Leonurus sibiricus

Nine undescribed labdane diterpenoids (1-9) and one undescribed ent-halimane diterpenoid (10) were isolated from the aerial parts of Leonurus sibiricus, together with four known analogues (11-14) during our searching for naturally occurring antitumor agents. Their structures were established by detailed spectroscopic analyses and electronic circular dichroism analysis. Compound 4 possessed a rare 10-epi labdane scaffold. All compounds except 5 were evaluated for their inhibitory activities against interleukin (IL)-6-stimulated signal transducer and activator of transcription (STAT3) expression using a luciferase reporter assay. Compound 1 showed the most inhibitory effect with the IC50 value 20.31 μM. Compound 1 inhibited the activation of JAK2/STAT3 signal pathway through binding to Gln326 of STAT3 in CNE cells. The antiproliferative evaluation of compound 1 against CNE, CAL-27, A549 and PANC-1 cells demonstrated that CNE cells were the most sensitive to 1. Furthermore, compound 1 showed moderate efficacy in inhibiting cell migration, invasion, and epithelial-mesenchymal transition in CNE cells. In addition, compound 1 also promoted ferroptosis in CNE cells in a dose-dependent manner. These results suggest that compound 1 might be a potential candidate lead for treating nasopharyngeal carcinoma.

Antibiotics May Interfere with Nivolumab Efficacy in Patients with Head and Neck Squamous Cell Carcinoma

INTRODUCTION

Patients with the head and neck squamous cell carcinoma (SCC) are often treated with immune checkpoint inhibitors (ICIs). Recently, antibiotic intake was reported to lower the efficacy of ICIs in patients with several types of cancers. However, it is unclear if antibiotics affect the efficacy of ICIs in patients with head and neck SCC. We retrospectively assessed the influence of antibiotics on the treatment efficacy of nivolumab, an ICI, in patients with head and neck SCC.

METHODS

We reviewed the medical records of patients with head and neck SCC treated with nivolumab at the Department of Medical Oncology, Tohoku University Hospital, between 2017 and 2021. Patients who received oral or intravenous antibiotics from a month before the day of nivolumab initiation to the day of the first imaging evaluation of ICI efficacy were assigned to the antibiotic-treated group. The remaining patients were assigned to the antibiotic-untreated group. The response rate (RR), progression-free survival (PFS), and overall survival time (OS) of both groups were compared.

RESULTS

Forty-five patients were assigned to the antibiotic-treated group and 19 to the antibiotic-untreated group. The RR, median PFS, and median OS of the antibiotic-treated group were 23.7%, 3.2 months (95% confidential interval [CI]: 2.0-4.1), and 8.4 months (95% CI: 5.3-15.1) and those of the antibiotic-untreated group were 42.1%, 5.8 months (95% CI: 2.3-16.7), and 18.4 months (95% CI: 6.2-23.1), respectively. The PFS of the antibiotic-untreated group was significantly longer than that of the antibiotic-treated group.

CONCLUSION

Our findings indicate that antibiotic treatment significantly shortens the PFS with nivolumab therapy in patients with head and neck SCC.

Comprehensive Geriatric Assessment and Quality of Life Aspects in Patients with Recurrent/Metastatic Head and Neck Squamous Cell Carcinoma (HNSCC)

To define frailty in older cancer patients, the aim of this study was to assess the geriatric status and quality of life (QoL) aspects in patients suffering from recurrent/metastatic head and neck squamous cell carcinoma (r/m HNSCC) under palliative treatment. A comprehensive geriatric assessment (CGA) was performed on 21 r/m HNSCC patients at two defined assessments, and the QoL aspects and the impact of descriptive data were evaluated. The Kolmogorov-Smirnov test, Spearman's rho correlation, and two-way mixed ANOVA were used for statistical analysis. All patients were found to be "frail". Pain, fatigue, and the burden of illness were the highest-rated symptoms. Oral function and orofacial appearance were highly impaired. A significant impact of descriptive data on the CGA and QoL results was found (all p ≤ 0.05). Thus, the CGA results revealed high frailty, severe comorbidities, and high impairments in QoL aspects. The CGA and QoL results were negatively affected by the primary HNSCC treatment approach, the need for prosthetic treatment, and worse oral functional capacity. Therefore, frailty in r/m HNSCC patients seems to be multidimensional. The evaluation of the CGA and QoL aspects in r/m HNSCC patients can be recommended to detect special needs, organize aftercare, and improve the support for frail and vulnerable cancer patients to create a multidisciplinary treatment approach.

Polymorphonuclear myeloid-derived suppressor cells and phosphatidylinositol-3 kinase gamma are critical to tobacco-mimicking oral carcinogenesis in mice

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a devastating disease most often associated with tobacco consumption that induces a field of mutations from which a tumor arises. Identification of ways to prevent the emergence of cancer in high-risk patients is an ultimate goal for combatting all types of cancer, including OSCC.

METHODS

Our study employs a mouse model of tongue carcinogenesis induced by tobacco carcinogen mimetic, 4-nitroquinoline 1-oxide (4NQO), to establish tongue dysplasia and OSCC. We use conventional histology, immunohistochemistry, multispectral imaging, mass cytometry, novel cell lines, pharmaceutical inhibition of PI3Kγ, T-cell suppression assays and mouse transplant models in our functional experimentation.

RESULTS

In our study, we identify Ly6G+ granulocytes as the most abundant immune cell type in a model of tongue carcinogenesis induced by tobacco carcinogen mimetic 4NQO. Targeting Ly6G+ granulocytes with a pharmacologic inhibitor of PI3Kγ, an isoform of PI3K exclusively expressed by myeloid cells, resulted in reduced tongue dysplasia severity, and reduced rates of OSCC. Importantly, we performed functional assays with the Ly6G+ granulocytes induced in cell line models of 4NQO carcinogenesis to demonstrate that these granulocytes have increased polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) activity against T-cell proliferation and these PMN-MDSCs play a functional role in promoting tumor formation by inhibiting tumor regression in a PI3Kγ-dependent manner.

CONCLUSIONS

Overall, our data suggest that recruitment of PMN-MDSCs to sites of dysplasia is critical to immune suppression of CD8 T cells, thereby permitting malignancy, and PI3Kγ inhibitors are one mechanism to reduce PMN-MDSC recruitment, immunosuppression and tumorigenesis in OSCC.

A pilot study of camrelizumab with docetaxel and cisplatin for the first line treatment in recurrent/metastatic oral squamous cell carcinoma

Pembrolizumab with cisplatin and 5-fluorouracil showed survival benefit but relatively high occurrence of treatment-related adverse events (TRAEs) for recurrent/metastatic oral squamous cell carcinoma (R/M OSCC). A more tolerable regime is needed. This trial enrolled 20 R/M OSCC patients with previously untreated and PD-L1 positive. Patients were administered camrelizumab with docetaxel and cisplatin every 3 weeks for six cycles, followed by camrelizumab monotherapy every 3 weeks until disease progression or intolerable toxicity. The primary endpoint was occurrence of grade ≥ 3 TRAEs, secondary endpoints included overall survival (OS), progression-free survival (PFS), and overall response rate (ORR). 45% patients experienced grade ≥ 3 TRAEs, which the most common were anemia (15%), stomatitis (15%), and neutropenia (10%). The most common potential immune-related adverse events were reactive cutaneous capillary endothelial proliferation (RCCEP; 60%), hypothyroidism (35%), and pneumonitis (15%). No treatment-related deaths occurred. The median OS, PFS, and ORR was 14.4 months, 5.35 months, and 40.0% respectively. The study also found RCCEP occurrence, lower FOXP3⁺ cells, and higher density of intratumor tertiary lymphoid structure were associated with improved efficacy. Our data suggest that camrelizumab with docetaxel/cisplatin as first-line therapy was well tolerable and had potentially favorite efficacy in PD-L1-positive patients with R/M OSCC.

Phase 4 Multinational Multicenter Retrospective and Prospective Real-World Study of Nivolumab in Recurrent and Metastatic Squamous Cell Carcinoma of the Head and Neck

This study examined the real-world use of nivolumab in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (R/M SCCHN). This was a multinational retrospective study (VOLUME) assessing treatment effectiveness and safety outcomes and a prospective study (VOLUME-PRO) assessing HRQoL and patient-reported symptoms. There were 447 and 51 patients in VOLUME and VOLUME-PRO, respectively. Across both studies, the median age was 64.0 years, 80.9% were male, and 52.6% were former smokers. Clinical outcomes of interest included real-world overall survival (rwOS) and real-world progression-free survival (rwPFS). The median rwOS was 9.2 months. Among patients with at least one assessment, 21.7% reported their best response as 'partial response', with 3.9% reporting 'complete response'. The median duration of response (DoR) and median rwPFS were 11.0 months and 3.9 months, respectively. At baseline, VOLUME-PRO patients reported difficulties relating to fatigue, physical and sexual functioning, dyspnea, nausea, sticky saliva, dry mouth, pain/discomfort, mobility, and financial difficulties. There were improvements in social functioning and financial difficulties throughout the study; however, no other clinically meaningful changes were noted. No new safety concerns were identified. This real-world, multinational, multicenter, retrospective and prospective study supports the effectiveness and safety of nivolumab for R/M SCCHN patients.

Sequential administration of PD‑1 inhibitor and cetuximab causes pneumonia

Severe drug-induced lung injury (DLI) has been reported to be associated with sequential administration of osimertinib, a third-generation tyrosine kinase inhibitor, following a programmed cell death ligand 1 (PD-L1) inhibitor. However, the relationship of sequential treatment with an anti-epidermal growth factor receptor (EGFR) antibody and PD-1 inhibitor with the risk of DLI remains to be elucidated. The present study conducted a retrospective review of the medical records of a total of 179 patients with head and neck cancer who had received treatment with cetuximab and/or a PD-1 inhibitor (nivolumab or pembrolizumab) at Chiba University Hospital (Chiba, Japan) between September 2014 and December 2020. The incidence of pneumonia and the clinical background characteristics of the patients were analyzed. The patients were classified into subgroups for analysis of the outcomes in this study: Patients who had received sequential, but not concurrent, cetuximab and PD-1 inhibitor treatment (Group C+P; n=43); patients who had received cetuximab-containing chemotherapy, but not a PD-1 inhibitor (Group C; n=101); and patients who had received PD-1 inhibitor-containing chemotherapy, but not cetuximab (Group P; n=35). The rates of DLI in the three groups were: Group C+P, 18.6%; Group C, 7.9%; and Group P, 11.4%. Prior use of ICI was not associated with any increase in the risk of DLI. DLI is seen frequently in patients receiving sequential PD-1 inhibitor and anti-EGFR antibody therapy.

Partial response to niraparib in combination with tislelizumab in a patient with metastatic undifferentiated tonsillar carcinoma: a case report and literature review

Undifferentiated tonsillar carcinoma is an extremely rare head and neck cancer. The treatment options are challenging due to insensitivity to chemotherapy and easy development of drug resistance. In this study, we reported a case of advanced undifferentiated tonsillar carcinoma with multiple mediastinal lymph node metastases that failed to respond to chemotherapy. Next-generation sequencing (NGS) revealed germline BReast CAncer gene (BRCA) 1 mutation and a high tumor mutational burden. Poly (adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors have demonstrated efficacy in solid tumors with BRCA1/2 mutations. Immune checkpoint inhibitors (ICIs) provide a treatment option for unresectable head and neck cancer. After local control treatment by embolization, niraparib and tislelizumab were administered to this patient. A partial response (PR) was achieved, and progression-free survival (PFS) and overall survival (OS) were 12 months and 19 months, respectively. This case reveals molecular profiling as an important therapeutic strategy for rare malignancies with no standard of care. Moreover, the underlying synergistic antitumor activity of PARPi and PD-L1 blockade was reviewed.

The current advances and future directions of PD-1/PD-L1 blockade in head and neck squamous cell carcinoma (HNSCC) in the era of immunotherapy

Immune checkpoint inhibitors (ICIs) have previously demonstrated their efficacy and safety in various solid tumors, and with the growing interest in the application of ICIs in head and neck squamous cell carcinoma (HNSCC), various data have been reported. Mechanistically, HNSCC cells express programmed death ligand 1 (PD-L1), which binds to its receptor programmed death 1 (PD-1). Immune escape plays a key role in disease initiation and progression. Studying the abnormal activation of related pathways of PD-1/PD-L1 will help to understand the way of immunotherapy and find the advantageous population of immunotherapy. How to reduce HNSCC-related mortality and morbidity in this process has promoted the search for new therapeutic strategies, especially in the era of immunotherapy. PD-1 inhibitors have demonstrated significant prolongation of survival in recurrent/metastatic (R/M) HNSCC with a favorable safety profile. It also holds great promise in locally advanced (LA) HNSCC, where numerous studies are underway. Although immunotherapy has made great progress in HNSCC research, there are still many challenges. Therefore, in the review, we conducted an in-depth study on the expression of PD-L1 and the regulatory, immunosuppressive mechanisms caused by PD-L1, especially in head and neck squamous cell carcinoma, which is different from other tumors. And further summarize the situation, challenges and development trends of PD-1 and PD-L1 blockade in clinical practice.

Patient-reported outcomes in immunotherapy for head and neck cancer

BACKGROUND

Data about patient-reported outcomes (PROs) among patients with head and neck squamous cell carcinoma (HNSCC) treated with immune checkpoint inhibitors are sparse. Our exploratory study evaluated PROs in patients with HNSCC starting treatment with immune checkpoint inhibitor monotherapy or combination therapy with cetuximab.

METHODS

Patients were recruited prior to receipt of their first checkpoint inhibitor therapy infusion. Participants completed measures of checkpoint inhibitor toxicities and quality of life (QOL) at on-treatment clinic visits.

RESULTS

Among patients treated with checkpoint inhibitor monotherapy (n = 48) or combination therapy (n = 38) toxicity increased over time (p < 0.05), while overall QOL improved from baseline to 12 weeks, with stable or declining QOL thereafter (p < 0.05). There were no group differences in change in toxicity index or QOL. Toxicity index scores were significantly higher in the combination group at 18-20 weeks and 6 months post-initiation of immune checkpoint inhibitor (p < 0.05). There were no significant group differences at baseline, the 6-8 week (p = 0.13) or 3-month (p = 0.09) evaluations. The combination group reported better emotional well-being at baseline than the monotherapy group (p = 0.04), There were no other group differences QOL at baseline or later timepoints.

CONCLUSIONS

Despite increasing patient-reported toxicity, checkpoint inhibitor monotherapy and combination therapy were associated with similar transient improvements, then worsening, of QOL in patients with HNSCC.

A novel metabolic-related gene signature for predicting clinical prognosis and immune microenvironment in head and neck squamous cell carcinoma

OBJECTIVES

Metabolic reprogramming is not only an essential hallmark in the progression of head and neck squamous cell carcinoma (HNSCC), but also an important regulator of cancer cell adaptation to tumor microenvironment (TME). However, the potential mechanism of metabolic reprogramming in TME of HNSCC is still unknown.

METHODS

The head and neck squamous cell carcinoma with survival information were obtained the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The metabolic-related genes were identified by differential analysis and survival analysis. Univariate and multivariate Cox regression analyses were applied to determine an overall estimate of metabolic-related risk signature and related clinical parameters. The sensitivity and specificity of the risk signature were evaluated by time-dependent receiver operation characteristic (ROC) curves. TME immune cell infiltration mediated by metabolic-related genes was explored by gene set enrichment analysis (GSEA) and correlation analysis.

RESULTS

Seven metabolic-related genes (SMS, MTHFD2, HPRT1, DNMT1, PYGL, ADA, and P4HA1) were identified to develop a metabolic-related risk signature. The low-risk group had a better overall survival compared to that of the high-risk group in the TCGA and GSE65858 cohorts. The AUCs for 1-, 3-, and 5-year overall survival were 0.646 vs. 0.673, 0.694 vs. 0.639, and 0.673 vs. 0.573, respectively. The AUC vale of risk score was 0.727 vs. 0.673. The low-risk group was associated with immune cell infiltration in the TME.

CONCLUSIONS

The metabolic-related risk signature were constructed and validated, which could involve in regulating the immune cell infiltration in the TME and act as an independent biomarker that predicted the prognosis of HNSCC.

Chemotherapy postimmunotherapy for recurrent metastatic head and neck squamous cell carcinoma

PURPOSE OF REVIEW

Clinical data on salvage chemotherapy used after checkpoints inhibitors in oncology are reviewed, with a special focus on recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC).

RECENT FINDINGS

Converging evidence is emerging about high response and/or disease control rates associated with salvage chemotherapy after immunotherapy failure in advanced solid tumours. This phenomenon is mainly reported in retrospective studies for "hot tumours" such as R/M HNSCC, melanoma, lung, urothelial or gastric cancers, but also in haematological malignancies. Some physiopathological hypotheses have been raised.

SUMMARY

Several independent series show increased response rates associated with postimmuno chemotherapy when compared with retrospective series in similar settings. Several mechanisms could be involved such as a "carry-over" allowed by a persistence of the checkpoint inhibitor, a modulation of tumour microenvironment components but also an intrinsic immunomodulatory effect of chemotherapy, increased by a specific immunologic state induced by the therapeutic pressure of checkpoint inhibitors. These data establish a rationale for prospectively evaluating the features of postimmunotherapy salvage chemotherapy.

Monoclonal antibodies for the treatment of squamous cell carcinoma: A literature review

BACKGROUND

Squamous cell carcinoma (SCC) is a relatively common and heterogenous malignancy of different organs, such as the skin, esophagus, and lungs. Although most cases experience good survival with surgical methods, management of advanced types of the disease remains challenging. Several modalities, including different chemotherapy regimens and immunotherapies, have been investigated in this matter, among which Monoclonal antibodies (Mabs) are one of the most promising ones. Since the development of Mabs, they have been widely used to treat different diseases. Mabs have shown significant efficacy with high specificity along with acceptable safety, which makes them a favorable option in cancer therapy. In this article, we aimed to review the different aspects of using Mabs in SCC therapy.

RECENT FINDINGS

We found that treating with different Mabs has shown excellent efficacy accompanied by acceptable safety in treating SCC of different organs. Therefore, Mabs are considered great options in the treatment of SCC, especially in advanced cases. Overall, two highly potent types of Mabs in SCC therapy are anti-EGFR Mabs and checkpoint inhibitors, especially Cetuximab, Nimotuzumab, and PD-1 inhibitors. Bevacizumab is also a promising option as adjuvant therapy to other modalities.

CONCLUSION

Although some Mabs have shown promising outcomes in SCC therapy, their application as a part of cancer treatment depends on further investigations regarding cost-effectiveness and predictors of response. FDA has approved several Mabs in SCC therapies, and Mabs may have a crucial role in this era in the near future, especially in treating head and neck and esophageal SCC and metastatic lung cancer.

Circulating CD137+ T Cell Levels Are Correlated with Response to Pembrolizumab Treatment in Advanced Head and Neck Cancer Patients

Pembrolizumab, an anti-PD-1 antibody, has been approved as first-line treatment for recurrent or metastatic head and neck squamous cell carcinoma ((R/M) HNSCC). However, only a minority of patients benefit from immunotherapy, which highlights the need to identify novel biomarkers to optimize treatment strategies. CD137⁺ T cells have been identified as tumour-specific T cells correlated with immunotherapy responses in several solid tumours. In this study, we investigated the role of circulating CD137⁺ T cells in (R/M) HNSCC patients undergoing pembrolizumab treatment. PBMCs obtained from 40 (R/M) HNSCC patients with a PD-L1 combined positive score (CPS) ≥1 were analysed at baseline via cytofluorimetry for the expression of CD137, and it was found that the percentage of CD3⁺CD137⁺ cells is correlated with the clinical benefit rate (CBR), PFS, and OS. The results show that levels of circulating CD137⁺ T cells are significantly higher in responder patients than in non-responders (p = 0.03). Moreover, patients with CD3⁺CD137⁺ percentage ≥1.65% had prolonged OS (p = 0.02) and PFS (p = 0.02). Multivariate analysis, on a combination of biological and clinical parameters, showed that high levels of CD3⁺CD137⁺ cells (≥1.65%) and performance status (PS) = 0 are independent prognostic factors of PFS (CD137⁺ T cells, p = 0.007; PS, p = 0.002) and OS (CD137⁺ T cells, p = 0.006; PS, p = 0.001). Our results suggest that levels of circulating CD137⁺ T cells could serve as biomarkers for predicting the response of (R/M) HNSCC patients to pembrolizumab treatment, thus contributing to the success of anti-cancer treatment.