Opportunities and Challenges in Combining Immunotherapy and Radiotherapy in Head and Neck Cancers

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

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

Prospective manipulation of the gut microbiome with microbial ecosystem therapeutic 4 (MET4) in HPV-related locoregionally-advanced oropharyngeal cancer squamous cell carcinoma (LA-OPSCC) undergoing primary chemoradiation: ROMA2 study

BACKGROUND

Gut microbiome modulation to boost antitumor immune responses is under investigation.

METHODS

ROMA-2 evaluated the microbial ecosystem therapeutic (MET)-4 oral consortia, a mixture of cultured human stool-derived immune-responsiveness associated bacteria, given with chemoradiation (CRT) in HPV-related oropharyngeal cancer patients. Co-primary endpoints were safety and changes in stool cumulative MET-4 taxa relative abundance (RA) by 16SRNA sequencing. Stools and plasma were collected pre/post-MET-4 intervention for microbiome and metabolome analysis.

RESULTS

Twenty-nine patients received ≥1 dose of MET-4 and were evaluable for safety: drug-related adverse events (AEs) occurred in 13/29 patients: all grade 1-2 except one grade 3 (diarrhea). MET-4 was discontinued early in 7/29 patients due to CRT-induced toxicity, and in 1/29 due to MET-4 AEs. Twenty patients were evaluable for ecological endpoints: there was no increase in stool MET-4 RA post-intervention but trended to increase in stage III patients (p = 0.06). MET-4 RA was higher in stage III vs I-II patients at week 4 (p = 0.03) and 2-month follow-up (p = 0.01), which correlated with changes in plasma and stool targeted metabolomics.

CONCLUSIONS

ROMA-2 did not meet its primary ecologic endpoint, as no engraftment was observed in the overall cohort. Exploratory findings of engraftment in stage III patients warrants further investigation of microbiome interventions in this subgroup.

Polygenic risk-stratified screening for nasopharyngeal carcinoma in high-risk endemic areas of China: a cost-effectiveness study

Background

Nasopharyngeal carcinoma (NPC) has an extremely high incidence rate in Southern China, resulting in a severe disease burden for the local population. Current EBV serologic screening is limited by false positives, and there is opportunity to integrate polygenic risk scores for personalized screening which may enhance cost-effectiveness and resource utilization.

Methods

A Markov model was developed based on epidemiological and genetic data specific to endemic areas of China, and further compared polygenic risk-stratified screening [subjects with a 10-year absolute risk (AR) greater than a threshold risk underwent EBV serological screening] to age-based screening (EBV serological screening for all subjects). For each initial screening age (30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64, and 65-69 years), a modeled cohort of 100,000 participants was screened until age 69, and then followed until age 79.

Results

Among subjects aged 30 to 54 years, polygenic risk-stratified screening strategies were more cost-effective than age-based screening strategies, and almost comprised the cost-effectiveness efficiency frontier. For men, screening strategies with a 1-year frequency and a 10-year absolute risk (AR) threshold of 0.7% or higher were cost-effective, with an incremental cost-effectiveness ratio (ICER) below the willingness to pay (¥203,810, twice the local per capita GDP). Specifically, the strategies with a 10-year AR threshold of 0.7% or 0.8% are the most cost-effective strategies, with an ICER ranging from ¥159,752 to ¥201,738 compared to lower-cost non-dominated strategies on the cost-effectiveness frontiers. The optimal strategies have a higher probability (29.4-35.8%) of being cost-effective compared to other strategies on the frontier. Additionally, they reduce the need for nasopharyngoscopies by 5.1-27.7% compared to optimal age-based strategies. Likewise, for women aged 30-54 years, the optimal strategy with a 0.3% threshold showed similar results. Among subjects aged 55 to 69 years, age-based screening strategies were more cost-effective for men, while no screening may be preferred for women.

Conclusion

Our economic evaluation found that the polygenic risk-stratified screening could improve the cost-effectiveness among individuals aged 30-54, providing valuable guidance for NPC prevention and control policies in endemic areas of China.

Identification of protein methyltransferases 5 associated with ferroptosis and immune cell infiltration of head and neck squamous cell carcinoma

Head and neck tumors are malignant tumors that appear in the head and neck. Although much progress has been made in the treatment of head and neck tumors, many challenges remain. The prognosis of some advanced cases remains poor and survival and quality of life after treatment face certain limitations. Therefore, further research into the pathogenesis and treatment options for head and neck tumors is important in order to improve the prognosis and quality of life of patients. The Protein Arginine Methyltransferase (PRMT) family is a class of enzymes that are responsible for adding methyl groups to arginine residues in proteins. PRMT family members play important roles in regulating many cellular processes, such as transcriptional regulation, signaling, and cell cycle regulation. Recent studies have shown that the PRMT family also plays an important function in tumorigenesis and development. Here, we found that PRMT family members are significantly overexpressed in head and neck tumors and that PRMT5 may serve as an independent prognostic factor in head and neck tumors. We found that PRMT5-regulated differential genes were significantly enriched in tumor-associated signaling pathways such as IL-17 and p53. And we also found that the expression of PRMT5 in head and neck tumors was significantly correlated with immune cell infiltration, m6A as well as the expression of ferroptosis-related genes, and drug sensitivity. These results suggest that PRMT may play an important role in the development of head and neck tumors.

Single cell analysis unveils the commonality and heterogeneity between nasopharyngeal and oropharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) and oropharyngeal carcinoma (OPC) are subtypes of head and neck cancer with different treatment effects due to the heterogeneity of tumor microenvironments. This study was to investigate the distinctive tumor microenvironments of NPC and OPC. Analyzing single-cell data from 10 cases of each subtype, we reveal significant differences in cellular composition, with NPC microenvironment dominated by T/NK and B cells, and OPC characterized by prevalent epithelial cells and fibroblasts. Dynamic transitions of CD8 T cells are observed in both tumor types, involving shifts from naivety to cytotoxicity, proliferation, and eventual exhaustion/exhausted states. Additionally, Tregs exhibit heightened proliferative abilities in later developmental stages, concomitant with exhaustion. These highly proliferative T cells and Tregs manifest elevated glycolysis and lactate metabolism activities. Furthermore, we explore intercellular communication between glycolytic malignant epithelial cells and these proliferative T cells. These findings offer comprehensive insights into the heterogeneity of tumor microenvironments and provide a solid foundation for future therapeutic strategies and targeted interventions.

Distinguishing immune checkpoint inhibitor-related pneumonitis from radiation pneumonitis by CT radiomics features in non-small cell lung cancer

PURPOSE

To develop a CT-based model to classify pneumonitis etiology in patients with non-small cell lung cancer(NSCLC) after radiotherapy(RT) and Immune checkpoint inhibitors(ICIs).

METHODS

We retrospectively identified 130 NSCLC patients who developed pneumonitis after receipt of ICIs only (n = 50), thoracic RT only (n = 50) (ICIs only + thoracic RT only, the training cohort, n = 100), and RT + ICIs (the test cohort, n = 30). Clinical and CT radiomics features were described and compared between different groups. We constructed a random forest (RF) classifier and a linear discriminant analysis (LDA) classifier by CT radiomics to discern pneumonitis etiology.

RESULTS

The patients in RT + ICIs group have more high grade (grade 3-4) pneumonitis compared to patients in ICIs only or RT only group (p < 0.05). Pneumonitis after the combined therapy was not a simple superposition mode of RT-related pneumonitis(RP) and ICI-related pneumonitis(CIP), resulting in the distinct characteristics of both RT and ICIs-related pneumonitis. The RF classifier showed favorable discrimination between RP and CIP with an area under the receiver operating curve (AUC) of 0.859 (95 %CI: 0.788-0.929) in the training cohort and 0.851 (95 % CI: 0.700-1) in the test cohort. The LDA classifier achieved an AUC of 0.881 (95 %CI: 0.815-0.947) in the training cohort and 0.842 (95 %CI: 0.686-0.997) in the test cohort. Our analysis revealed four principal CT-based features shared across both models:original_glrlm_LongRunLowGrayLevelEmphasis, wavelet-HLL_firstorder_Median, wavelet-LLL_ngtdm_Busyness， and wavelet-LLL_glcm_JointAverage.

CONCLUSION

CT radiomics-based classifiers could provide a noninvasive method to identify the predominant etiology in NSCLC patients who developed pneumonitis after RT alone, ICIs alone or RT + ICIs.

Pan-cancer analysis of TIM-3 transcriptomic expression reveals high levels in pancreatic cancer and interpatient heterogeneity

BACKGROUND

T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), an immune checkpoint receptor, dampens immune function. TIM-3 antagonists have entered the clinic.

METHODS

We analyzed TIM-3 transcriptomic expression in 514 diverse cancers. Transcript abundance was normalized to internal housekeeping genes and ranked (0-100 percentile) to a reference population (735 tumors; 35 histologies [high≥75 percentile rank]). Ninety tumors (17.5%) demonstrated high TIM-3 expression.

RESULTS

TIM-3 expression varied between and within tumor types. However, high TIM-3 expression was more common in pancreatic cancer (20/55 tumors, 36.4%; odds ratio, 95% confidence interval (pancreatic vs. other tumors) = 3.176 (1.733-5.818; p < 0.001, multivariate]). High TIM-3 also significantly and independently correlated with high PD-L1 (p = 0.014) and high CTLA-4 (p < 0.001) transcriptomic expression (multivariate).

CONCLUSIONS

These observations indicate that TIM-3 RNA expression is heterogeneous, but more common in pancreatic cancer and in tumors exploiting PD-L1 and CTLA-4 checkpoints. Clinical trials with patient selection for matched immune-targeted combinations may be warranted.

Radiation-sensitive genetic prognostic model identifies individuals at risk for radiation resistance in head and neck squamous cell carcinoma

BACKGROUND

The advantages of radiotherapy for head and neck squamous cell carcinoma (HNSCC) depend on the radiation sensitivity of the patient. Here, we established and verified radiological factor-related gene signature and built a prognostic risk model to predict whether radiotherapy would be beneficial.

METHODS

Data from The Cancer Genome Atlas, Gene Expression Omnibus, and RadAtlas databases were subjected to LASSO regression, univariate COX regression, and multivariate COX regression analyses to integrate genomic and clinical information from patients with HNSCC. HNSCC radiation-related prognostic genes were identified, and patients classified into high- and low-risk groups, based on risk scores. Variations in radiation sensitivity according to immunological microenvironment, functional pathways, and immunotherapy response were investigated. Finally, the expression of HNSCC radiation-related genes was verified by qRT-PCR.

RESULTS

We built a clinical risk prediction model comprising a 15-gene signature and used it to divide patients into two groups based on their susceptibility to radiation: radiation-sensitive and radiation-resistant. Overall survival was significantly greater in the radiation-sensitive than the radiation-resistant group. Further, our model was an independent predictor of radiotherapy response, outperforming other clinical parameters, and could be combined with tumor mutational burden, to identify the target population with good predictive value for prognosis at 1, 2, and 3 years. Additionally, the radiation-resistant group was more vulnerable to low levels of immune infiltration, which are significantly associated with DNA damage repair, hypoxia, and cell cycle regulation. Tumor Immune Dysfunction and Exclusion scores also suggested that the resistant group would respond less favorably to immunotherapy.

CONCLUSIONS

Our prognostic model based on a radiation-related gene signature has potential for application as a tool for risk stratification of radiation therapy for patients with HNSCC, helping to identify candidates for radiation therapy and overcome radiation resistance.

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.

Immunotherapy with PD-1 Inhibitor Nivolumab in Recurrent/Metastatic Platinum Refractory Head and Neck Cancers-Early Experiences from Romania and Literature Review

Prognosis in recurrent/metastatic head and neck squamous-cell carcinoma (HNSCC) refractory to platinum-based chemotherapy is poor, making therapy optimization a priority. Anti-programmed cell death protein 1 (anti-PD-1) monoclonal antibody Nivolumab was approved in such cases. We present the early experience with Nivolumab immunotherapy at three cancer clinics from south and northeast Romania, aiming to describe the main characteristics and outcomes relative to literature reports, and to suggest patient selection criteria. Diagnostic, clinical, biological, therapeutic, and outcomes-related data from January 2020 until March 2023 were analyzed retrospectively. Eighteen patients with platinum refractory HNSCC (85.7% men, median age 58.9) were administered Nivolumab for 1-14 months (median 5.6 months) in addition to other treatments (surgery, radiotherapy, chemotherapy), and monitored for up to 25 months. Median neutrophil-to-lymphocyte ratio (NLR) ranged from 2.72 initially to 6.01 during treatment. Overall survival (OS) was 16 months, and patients who died early had the sharpest NLR increases (13.07/month). There were no severe immune-related adverse events. Lower NLR values and combined intensive chemotherapy, radiotherapy, and immunotherapy were related to better outcomes. To our knowledge, we also report the first two cases of second primary malignancy (SPM) in the head and neck region treated with Nivolumab in Romania (for which the sequential administration of radiotherapy and immunotherapy seems better). The work of other Romanian authors on the role of HPV status in HNC is also discussed. Multi-center trials are needed in order to investigate and confirm these observations.

The current understanding of the immune landscape relative to radiotherapy across tumor types

Radiotherapy is part of the standard of care treatment for a great majority of cancer patients. As a result of radiation, both tumor cells and the environment around them are affected directly by radiation, which mainly primes but also might limit the immune response. Multiple immune factors play a role in cancer progression and response to radiotherapy, including the immune tumor microenvironment and systemic immunity referred to as the immune landscape. A heterogeneous tumor microenvironment and the varying patient characteristics complicate the dynamic relationship between radiotherapy and this immune landscape. In this review, we will present the current overview of the immunological landscape in relation to radiotherapy in order to provide insight and encourage research to further improve cancer treatment. An investigation into the impact of radiation therapy on the immune landscape showed in several cancers a common pattern of immunological responses after radiation. Radiation leads to an upsurge in infiltrating T lymphocytes and the expression of programmed death ligand 1 (PD-L1) which can hint at a benefit for the patient when combined with immunotherapy. In spite of this, lymphopenia in the tumor microenvironment of 'cold' tumors or caused by radiation is considered to be an important obstacle to the patient's survival. In several cancers, a rise in the immunosuppressive populations is seen after radiation, mainly pro-tumoral M2 macrophages and myeloid-derived suppressor cells (MDSCs). As a final point, we will highlight how the radiation parameters themselves can influence the immune system and, therefore, be exploited to the advantage of the patient.

Cytoplasmic poly(A)-binding protein 1 (PABPC1) is a prognostic biomarker to predict survival in nasopharyngeal carcinoma regardless of chemoradiotherapy

BACKGROUND

Nasopharyngeal carcinoma (NPC), especially the nonkeratinizing type, is a malignant tumor primarily occurring in southern China and Southeast Asia. Chemotherapy (CT) and combined radiotherapy (RT) is used to treat NPC. However, the mortality rate is high in recurrent and metastatic NPC. We developed a molecular marker, analyzed its correlation with clinical characteristics, and assessed the prognostic value among NPC patients with or without chemoradiotherapy.

METHODS

A total of 157 NPC patients were included in this study, with 120 undergoing treatment and 37 without treatment. EBER1/2 expression was investigated using in situ hybridization (ISH). Expression of PABPC1, Ki-67, and p53 was detected with immunohistochemistry. The correlations of EBER1/2 and the expression of the three proteins having clinical features and prognosis were evaluated.

RESULTS

The expression of PABPC1 was associated with age, recurrence, and treatment but not with gender, TNM classification, or the expression of Ki-67, p53, or EBER. High expression of PABPC1 was associated with poor overall survival (OS) and disease-free survival (DFS) and was an independent predictor depending on multivariate analysis. Comparatively, no significant correlation was observed between the expression of p53, Ki-67, and EBER and survival. In this study, 120 patients received treatments and revealed significantly better OS and DFS than the untreated 37 patients. PABPC1 high expression was an independent predictor of shorter OS in the treated (HR = 4.012 (1.238-13.522), 95% CI, p = 0.021) and the untreated groups (HR = 5.473 (1.051-28.508), 95% CI, p = 0.044). However, it was not an independent predictor of shorter DFS in either the treated or the untreated groups. No significant survival difference was observed between patients with docetaxel-based induction chemotherapy (IC) + concurrent chemoradiotherapy (CCRT) and those with paclitaxel-based IC + CCRT. However, when combined with treatment and PABPC1 expression, patients with paclitaxel-added chemoradiotherapy plus PABPC1 low expression had significantly better OS than those who underwent chemoradiotherapy (p = 0.036).

CONCLUSIONS

High expression of PABPC1 is associated with poorer OS and DFS among NPC patients. Patients with PABPC1 having low expression revealed good survival irrespective of the treatment received, indicating that PABPC1 could be a potential biomarker for triaging NPC patients.