Correlation of PD-L1 Expression of Tumor Cells with Survival Outcomes after Radical Intensity-Modulated Radiation Therapy for Non-Metastatic Nasopharyngeal Carcinoma

Recent Advances in Assessing the Clinical Implications of Epstein-Barr Virus Infection and Their Application to the Diagnosis and Treatment of Nasopharyngeal Carcinoma

Reports about the oncogenic mechanisms underlying nasopharyngeal carcinoma (NPC) have been accumulating since the discovery of Epstein-Barr virus (EBV) in NPC cells. EBV is the primary causative agent of NPC. EBV-host and tumor-immune system interactions underlie the unique representative pathology of NPC, which is an undifferentiated cancer cell with extensive lymphocyte infiltration. Recent advances in the understanding of immune evasion and checkpoints have changed the treatment of NPC in clinical settings. The main EBV genes involved in NPC are LMP1, which is the primary EBV oncogene, and BZLF1, which induces the lytic phase of EBV. These two multifunctional genes affect host cell behavior, including the tumor-immune microenvironment and EBV behavior. Latent infections, elevated concentrations of the anti-EBV antibody and plasma EBV DNA have been used as biomarkers of EBV-associated NPC. The massive infiltration of lymphocytes in the stroma suggests the immunogenic characteristics of NPC as a virus-infected tumor and, at the same time, also indicates the presence of a sophisticated immunosuppressive system within NPC tumors. In fact, immune checkpoint inhibitors have shown promise in improving the prognosis of NPC patients with recurrent and metastatic disease. However, patients with advanced NPC still require invasive treatments. Therefore, there is a pressing need to develop an effective screening system for early-stage detection of NPC in patients. Various modalities, such as nasopharyngeal cytology, cell-free DNA methylation, and deep learning-assisted nasopharyngeal endoscopy for screening and diagnosis, have been introduced. Each modality has its advantages and disadvantages. A reciprocal combination of these modalities will improve screening and early diagnosis of NPC.

Combinations of radiotherapy with immunotherapy in nasopharyngeal carcinoma

BACKGROUND

The treatment of nasopharyngeal carcinoma (NPC) is currently based on concurrent chemoradiotherapy. The prognosis of early NPC is better, while the prognosis of advanced NPC is poor. Immunotherapy is becoming increasingly commonly employed in clinical practice as a new strategy for treating malignant tumors. It has shown promising results in the treatment of certain malignant tumors, making it a current clinical research hotspot.

METHODS

This review summarizes the current immunotherapy on NPC, highlighting the application of immunotherapy and radiotherapy in the treatment of NPC.

RESULTS

X-rays can either increase or suppress anti-tumor immune responses through various pathways and mechanisms. Immune checkpoint inhibitors can usually enhance X-ray-induced anti-tumor immune responses. Detecting the immune checkpoint markers and tumor mutation markers, and the functional status of effector cells in patients can aid in the development of individualized treatment that improves the treatment efficacy with reducing drug resistance and adverse reactions. The development of a multivalent vaccine for NPC will help improve the efficacy of the vaccine. Combining techniques that increase the tumor antigens release, such as radiotherapy and oncolytic virus vaccines, may enhance the ability of the immune response.

CONCLUSIONS

To shed further light on the application of immunotherapy in NPC, large pooled studies must accumulate sufficient cases with detailed exposure data.

Efficacy and safety of PD-1 inhibitors in recurrent or metastatic nasopharyngeal carcinoma patients after failure of platinum-containing regimens: a systematic review and meta-analysis

OBJECTIVE

There is a lack of standard salvage treatment options for recurrent or metastatic nasopharyngeal carcinoma (RM-NPC) that has failed platinum-containing regimens. Breakthroughs in immunotherapy have opened up new options for these patients. However, the efficacy and safety of immunotherapy have not been clarified. This study aimed to summarize and assess the efficacy and safety of PD-1 inhibitors in patients with RM-NPC who failed platinum-containing chemotherapy.

METHODS

Up to August 25, 2022, clinical trials of PD-1 inhibitors in RM-NPC patients who failed platinum-containing regimens were searched in the PubMed, Embase, Cochrane, and Web of Science databases. Retrieval subject terms included "nasopharyngeal carcinoma", "metastatic", "recurrence", "PD-1", and "PD-L1". The clinical trials eligible for inclusion were systematically reviewed and meta-analyzed.

RESULTS

A total of 9 studies including 842 patients with RM-NPC were included in this meta-analysis. The results showed that PD-1 inhibitors had promising efficacy in patients with RM-NPC who failed platinum-containing regimens: objective response rate (ORR) was 24% (95% confidence interval [CI] 21-26%), disease control rate (DCR) was 52% (95% CI 45-58%), 1-year progression-free survival (PFS) rate was 25% (95% CI 18-32%), and 1-year overall survival (OS) rate was 53% (95% CI 37-68%). In terms of treatment-related adverse events (AEs), the incidence of grade ≥ 3 treatment-related AEs was 19% (95% CI 13-24%). In addition, we found that PD-1 inhibitors were more effective in patients with PD-L1 positive than in patients with PD-L1 negative nasopharyngeal carcinoma who had failed platinum-containing regimens (ORR 31% (95%CI 26-35%) vs. 21% (95% CI 17-25%)).

CONCLUSION

PD-1 inhibitors may provide a survival benefit for patients with RM-NPC who have failed platinum-containing regimens and have the advantage of a good safety profile, making them a promising treatment option.

A case report and literature review on reactive cutaneous capillary endothelial proliferation induced by camrelizumab in a nasopharyngeal carcinoma patient

Camrelizumab, a monoclonal antibody, blocks programmed cell death protein-1 from binding to T cells and programmed cell death ligand 1 on tumor cells, thereby ensuring sustained T cell activation and blocking immune escape of various types of cancer, including nasopharyngeal carcinoma. Reactive cutaneous capillary endothelial hyperplasia (RCCEP) is the most common immune-related adverse event in patients treated with camrelizumab. We report a case nasopharyngeal carcinoma in a patient with camrelizumab-induced RCCEP. A 68-year-old man diagnosed with nasopharyngeal carcinoma developed RCCEP at multiple locations after 3 months of camrelizumab treatment. RCCEP of the right lower eyelid affected closure of the right eye. In this report, we also reviewed previous literature on camrelizumab-induced RCCEP. In summary, the mechanism underlying camrelizumab-induced RCCEP remains unclear. RCCEP typically gradually subsides after discontinuing camrelizumab treatment. Larger nodules can be treated with lasers, ligation, or surgery. Although surgical excision is effective, RCCEP may recur in patients undergoing camrelizumab treatment. RCCEP management may not be required in the absence of adverse effects on the patient's daily life.

Precision medicine in nasopharyngeal carcinoma: comprehensive review of past, present, and future prospect

Nasopharyngeal carcinoma (NPC) is an aggressive malignancy with high propensity for lymphatic spread and distant metastasis. It is prominent as an endemic malignancy in Southern China and Southeast Asia regions. Studies on NPC pathogenesis mechanism in the past decades such as through Epstein Barr Virus (EBV) infection and oncogenic molecular aberrations have explored several potential targets for therapy and diagnosis. The EBV infection introduces oncoviral proteins that consequently hyperactivate many promitotic pathways and block cell-death inducers. EBV infection is so prevalent in NPC patients such that EBV serological tests were used to diagnose and screen NPC patients. On the other hand, as the downstream effectors of oncogenic mechanisms, the promitotic pathways can potentially be exploited therapeutically. With the apparent heterogeneity and distinct molecular aberrations of NPC tumor, the focus has turned into a more personalized treatment in NPC. Herein in this comprehensive review, we depict the current status of screening, diagnosis, treatment, and prevention in NPC. Subsequently, based on the limitations on those aspects, we look at their potential improvements in moving towards the path of precision medicine. The importance of recent advances on the key molecular aberration involved in pathogenesis of NPC for precision medicine progression has also been reported in the present review. Besides, the challenge and future outlook of NPC management will also be highlighted.

The efficacy and safety of VEGF/VEGFR inhibitors in patients with recurrent or metastatic nasopharyngeal carcinoma: A meta-analysis

OBJECTIVES

Molecular targeted therapies against vascular endothelial growth factor (VEGF) receptor (VEGFR) have been explored in the treatment of recurrent or metastatic nasopharyngeal carcinoma (rmNPC). We conducted a meta-analysis to evaluate the efficacy and safety of VEGF/VEGFR inhibitors for treating rmNPC.

MATERIALS AND METHODS

Electronic databases were searched for eligible literature. Data on the objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), median overall survival (mOS), PFS rate, OS rate, and drug-related adverse events (AEs) were extracted.

RESULTS

A total of 10 studies (published in 9 articles) that involved 357 patients were included. The pooled ORR was 37 % (95 % confidence interval [CI]: 17-60 %), the DCR was 70 % (95 % CI: 51-85 %), the mPFS was 5.69 months (95 % CI: 4.52-6.86), the mOS was 12.61 months (95 % CI: 10.23-14.99), the 1-year PFS rate was 34 % (95 % CI: 25-44 %), and the 1-year OS rate was 62 % (95 % CI: 38-83 %). The pooled incidence of grade 3/4 drug-related AEs was 27 %, while that of grade 5 AEs was 0.22 %. Further subgroup analysis showed that the pooled ORR and DCR for first-line VEGF inhibitors were 80 % (95 % CI: 74-86 %) and 94 % (CI: 82-100 %), respectively.

CONCLUSION

Our meta-analysis is the first report to demonstrate the efficacy and safety of VEGF/VEGFR inhibitors in patients with rmNPC. Targeting VEGF/VEGFR therapy added to first-line chemotherapy achieved an excellent ORR and DCR, while the improvement in response rates did not translate to a prominent OS benefit.

Prognostic value of PD-1, PD-L1 and PD-L2 deserves attention in head and neck cancer

Head and neck cancer has high heterogeneity with poor prognosis, and emerging researches have been focusing on the prognostic markers of head and neck cancer. PD-L1 expression is an important basis for strategies of immunosuppressive treatment, but whether it has prognostic value is still controversial. Although meta-analysis on PD-L1 expression versus head and neck cancer prognosis has been performed, the conclusions are controversial. Since PD-L1 and PD-L2 are two receptors for PD-1, here we summarize and analyze the different prognostic values of PD-1, PD-L1, and PD-L2 in head and neck cancer in the context of different cell types, tissue localization and protein forms. We propose that for head and neck cancer, the risk warning value of PD-1/PD-L1 expression in precancerous lesions is worthy of attention, and the prognostic value of PD-L1 expression at different subcellular levels as well as the judgment convenience of prognostic value of PD-1, PD-L1, PD-L2 should be fully considered. The PD-L1 evaluation systems established based on immune checkpoint inhibitors (ICIs) are not fully suitable for the evaluation of PD-L1 prognosis in head and neck cancer. It is necessary to establish a new PD-L1 evaluation system based on the prognosis for further explorations. The prognostic value of PD-L1, PD-L2 expression in head and neck cancer may be different for early-stage and late-stage samples, and further stratification is required.

Gambogic acid suppresses nasopharyngeal carcinoma via rewiring molecular network of cancer malignancy and immunosurveillance

Nasopharyngeal carcinoma (NPC) is a malignant tumor highly prevalent in Southeast Asia. The distant metastasis and disease recurrence are still unsolved clinical problems. In recent years, traditional Chinese medicine (TCM) monomers have become significantly attractive due to their advantages. Using high throughput drug sensitivity screening, we identified gambogic acid (GA) as a common TCM monomer displaying multiple anti-NPC effects. GA could effectively inhibit the proliferation of low differentiated cells and highly metastatic cells in NPC via inducing apoptosis and G2/M cell cycle arrest. In addition, GA obviously repressed the abilities of cell clone, migration, invasion, angiogenesis and represented satisfied synergistic effects combined with chemotherapy. Importantly, we found the elevated immune checkpoint CD47 stimulated after chemotherapy was dramatically impaired by GA treatment. Mechanically, the network pharmacology analyses unraveled that the oncogenic signaling pathways including STATs were rewired by GA treatment. Taken together, our study reveals a molecular basis and provides a rationale for GA application as the treatment regime in NPC therapy in future.

Optimal management of recurrent and metastatic upper tract urothelial carcinoma: Implications of intensity modulated radiation therapy

BACKGROUND

Upper tract urothelial carcinoma (UTUC) is rare and the treatment for recurrent or metastatic UTUC is unclear. We evaluated the outcomes of salvage and palliative radiotherapy (RT) and prognostic factors in UTUC patients and find implications for salvage and palliative RT.

METHODS

Between August 2006 and February 2021, 174 patients (median age, 68 years; range, 37-90) underwent salvage and palliative RT. Disease status at RT included initially diagnosed advanced disease (n = 8, 4.6%), local recurrence only (n = 56, 32.2%), distant metastasis only (n = 59, 33.9%), and local recurrence and distant metastasis (n = 51, 29.3%). The primary tumor location included the renal pelvis (n = 87, 50%), ureter (n = 77, 44.3%), and both (n = 10, 5.7%). Radical nephroureterectomy, chemotherapy, and immunotherapy were used in 135 (77.6%), 101 (58%), and 19 (10.9%) patients, respectively. Survival outcomes and prognostic factors were analysed using Cox and logistic regression analysis.

RESULTS

Salvage RT and palliative RT was administered in 73 (42%) and 101 (58%) patients, respectively. The median radiation dose was 45 Gy (range, 15-65). Two-dimensional (2D) or three-dimensional (3D) RT and intensity modulated RT (IMRT) were used in 61 (35.1%) and 113 (64.9%) patients, respectively. The median follow-up was 7.8 months. The median duration of overall survival (OS) was 13.4 months, and the 1-year OS was 53.5%. The median progression-free survival (PFS) was 4.7 months, and the 6-month PFS was 41.9%. The 6-month infield PFS was 84%. In multivariate analysis, RT method (2D/3D vs. IMRT, p = 0.007) and RT response (p = 0.008) were independent prognostic factors for OS, and RT response correlated with PFS (p = 0.015). In subgroup analysis in patients with PD-L1 data, positive PD-L1 correlated with better PFS (p = 0.009). RT response-associated factors were concurrent chemotherapy (p = 0.03) and higher radiation dose (p = 0.034). Of 145 patients, 10 (6.9%) developed grade 3 acute or late toxicity.

CONCLUSIONS

Salvage and palliative RT for UTUC are feasible and effective. Patients with RT response using IMRT may have survival benefit from salvage and palliative RT. Positive PD-L1 status might be related to radiosensitivity. High-dose radiation with concurrent chemotherapy may improve RT response.

Prognostic Value of Programmed Death Ligand-1 Expression in Solid Tumors Irrespective of Immunotherapy Exposure: A Systematic Review and Meta-Analysis

BACKGROUND

The programmed cell death-1/programmed cell death ligand-1 (PD-L1) pathway, which plays a crucial role in cancer immune surveillance, is the target of several approved immunotherapeutic agents and is used as a predictive biomarker in some solid tumors. However, its use as a prognostic marker (i.e., regardless of therapy used) is not established clearly with available data demonstrating inconsistent prognostic impact of PD-L1 expression in solid tumors.

METHODS

We conducted a systematic literature search of electronic databases and identified publications exploring the effect of PD-L1 expression on overall survival and/or disease-free survival. Hazard ratios were pooled in a meta-analysis using generic inverse-variance and random-effects modeling. We used the Deeks method to explore subgroup differences based on disease site, stage of disease, and method of PD-L1 quantification.

RESULTS

One hundred and eighty-six studies met the inclusion criteria. Programmed cell death ligand-1 expression was associated with worse overall survival (hazard ratio 1.33, 95% confidence interval 1.26-1.39; p < 0.001). There was significant heterogeneity between disease sites (subgroup p = 0.002) with pancreatic, hepatocellular, and genitourinary cancers associated with the highest magnitude of adverse outcomes. Programmed cell death ligand-1 was also associated with worse overall disease-free survival (hazard ratio 1.19, 95% confidence interval 1.09-1.30; p < 0.001). Stage of disease did not significantly affect the results (subgroup p = 0.52), nor did the method of quantification via immunohistochemistry or messenger RNA (subgroup p = 0.70).

CONCLUSIONS

High expression of PD-L1 is associated with worse survival in solid tumors albeit with significant heterogeneity among tumor types. The effect is consistent in early-stage and metastatic disease and is not sensitive to method of PD-L1 quantification. These data can provide additional information for the counseling of patients with cancer about prognosis.

Combined Association of Tumoral PD-L1 Expression and Pretreatment Presence of Epstein-Barr Virus DNA With Risk Stratification and Prognosis of Patients With Nasopharyngeal Carcinoma

Background

Little is known about whether the combination of tumor programmed death-ligand 1 (PD-L1) expression and pretreatment EBV DNA status can help stratify nasopharyngeal carcinoma (NPC) patients by risk of metastasis or predict prognosis.

Methods

PD-L1 expression was assessed using immunohistochemical staining of 78 non-keratinizing NPC patients with clinical data. Survival outcomes and independent prognostic factors were identified.

Results

Seventy-eight patients were included, high PD-L1 expression was observed in 25 of 43 patients (58%) with metastasis, while it was observed only in 7 of 35 patients (20%) without metastasis. Multivariate analyses showed that progression-free survival (PFS) was independently predicted by tumoral PD-L1 expression and pretreatment EBV DNA status. When combining, 93.75% patients with high PD-L1 and EBV infection developed distant metastasis, and those patients were associated with worse PFS.

Conclusions

Both PD-L1 expression and pretreatment EBV DNA are closely related to metastasis and prognosis of NPC patients. Their combination can facilitate risk stratification and prognosis prediction, which may improve disease treatment and management.

Nasopharyngeal carcinoma: an evolving paradigm

The past three decades have borne witness to many advances in the understanding of the molecular biology and treatment of nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV)-associated cancer endemic to southern China, southeast Asia and north Africa. In this Review, we provide a comprehensive, interdisciplinary overview of key research findings regarding NPC pathogenesis, treatment, screening and biomarker development. We describe how technological advances have led to the advent of proton therapy and other contemporary radiotherapy approaches, and emphasize the relentless efforts to identify the optimal sequencing of chemotherapy with radiotherapy through decades of clinical trials. Basic research into the pathogenic role of EBV and the genomic, epigenomic and immune landscape of NPC has laid the foundations of translational research. The latter, in turn, has led to the development of new biomarkers and therapeutic targets and of improved approaches for individualizing immunotherapy and targeted therapies for patients with NPC. We provide historical context to illustrate the effect of these advances on treatment outcomes at present. We describe current preclinical and clinical challenges and controversies in the hope of providing insights for future investigation.

Expression of cancer cell-intrinsic PD-1 associates with PD-L1 and p-S6 and predicts a good prognosis in nasopharyngeal carcinoma

Aims: Programmed cell death ligand 1 (PD-L1) is the ligand of programmed death 1 (PD-1), which is a host immunity inhibitory receptor. Expression of PD-L1 in diverse tumor types has been widely discussed, while there is little research about tumor intrinsic-PD-1. Phospho-S6 (p-S6) is an important downstream effector in the PI3K/AKT/mTOR pathway. Our study was focused on investigating expression of cancer cell-intrinsic PD-1, PD-L1 and p-S6 proteins and aimed to illustrate their relationship and clinical significances in nasopharyngeal carcinoma (NPC). Methods: The expression of PD-1, PD-L1 and p-S6 proteins in tissues of NPC, non-cancerous nasopharyngeal epithelia, primary cancer and matching metastatic lesion was detected by immunohistochemistry. Results: Expression of PD-1, PD-L1 and p-S6 proteins and co-expression of PD-1 and PD-L1 were significantly higher in NPC (all P<0.05). The expression of PD-1 and co-expression of PD-1 and PD-L1 in paired metastatic NPC were significantly increased (all P<0.01). NPC patients with positive expression of PD-L1 showed significantly higher overall survival rate (P =0.035). However, NPC patients with positive expression PD-1 and p-S6 showed significantly lower overall survival rate (P =0.031, P=0.044, respectively). Interestingly, NPC patients with co-expression of PD-1 and PD-L1 had lower overall survival rate (P=0.042). Multivariate Cox proportional hazard regression analysis confirmed that positive expression of PD-L1 and p-S6 were independent prognostic factors for NPC patients. Conclusions: Expression of cancer cell-intrinsic PD-1 associates with PD-L1 and p-S6 proteins, PD-L1 might serve as a good prognostic biomarker, while p-S6 could be an independent poor prognostic biomarker for NPC patients.

PD-L1 Expression is Highly Associated with Tumor-Associated Macrophage Infiltration in Nasopharyngeal Carcinoma

Purpose

Tumour-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment and provide a barrier against the cytotoxic effector functions of T cells and natural killer (NK) cells. Recently, TAMs have become increasingly recognised as an attractive target in combination therapy with PD-1/PD-L1 immuno-checkpoint blockades (ICBs). However, the relationship between PD-L1 expression and TAMs remains unknown in nasopharyngeal carcinoma (NPC).

Patients and Methods

A total of 212 NPC patients from Nanfang hospital were collected in this study. We evaluated the expression of PD-L1 in tumor cells, CD68 (pan-macrophages), and CD163 (M2-like macrophage) in NPC tissues using immunohistochemical (IHC) staining.

Results

The positivity of PD-L1 on tumor cells was 61.3% (130/212). The infiltration densities of CD68+ cells and CD163+ cells in PD-L1-positive NPC tissues were significantly higher than those in PD-L1-negative NPC tissues (P=0.0012 for CD68; P<0.0001 for CD163). Logistic regression analysis showed that high densities of CD68+ macrophages and CD163+ TAMs were significantly associated with increased PD-L1 expression. Subgroup analyses demonstrated that a positive PD-L1 expression on tumor cells in combination with lower CD163+ TAMs density was significantly associated with favorable prognosis, whereas negative PD-L1 expression on tumor cells with higher CD163+ TAMs density was associated with worse prognosis.

Conclusion

The PD-L1 expression in tumor cells was positively correlated with TAMs density in tumor microenvironment of NPC, suggesting TAMs as a new target for combination therapy to improve the response rate of ICBs in NPC treatment.

Reprogramming the tumour microenvironment by radiotherapy: implications for radiotherapy and immunotherapy combinations

Radiotherapy (RT) is a highly effective anti-cancer therapy delivered to around 50-60% of patients. It is part of therapy for around 40% of cancer patients who are cured of their disease. Until recently, the focus of this anti-tumour efficacy has been on the direct tumour cytotoxicity and RT-induced DNA damage. Recently, the immunomodulatory effects of RT on the tumour microenvironment have increasingly been recognized. There is now intense interest in potentially using RT to induce an anti-tumour immune response, which has led to rethinking into how the efficacy of RT could be further enhanced. Following the breakthrough of immune check point inhibitors (ICIs), a new era of immuno-oncology (IO) agents has emerged and established immunotherapy as a routine part of cancer treatment. Despite ICI improving outcomes in many cancer types, overall durable responses occur in only a minority of patients. The immunostimulatory effects of RT make combinations with ICI attractive to potentially amplify anti-tumour immunity resulting in increased tumour responses and improved outcomes. In contrast, tumours with profoundly immunosuppressive tumour microenvironments, dominated by myeloid-derived cell populations, remain a greater clinical challenge and RT may potentially further enhance the immunosuppression. To harness the full potential of RT and IO agent combinations, further insights are required to enhance our understanding of the role these immunosuppressive myeloid populations play, how RT influences these populations and how they may be therapeutically manipulated in combination with RT to improve outcomes further. These are exciting times with increasing numbers of IO targets being discovered and IO agents undergoing clinical evaluation. Multidisciplinary research collaborations will be required to establish the optimal parameters for delivering RT (target volume, dose and fractionation) in combination with IO agents, including scheduling to achieve maximal therapeutic efficacy.

Recent Advances in the Development of Biomarkers and Chemoradiotherapeutic Approaches for Nasopharyngeal Carcinoma

Epstein-Barr virus (EBV) associated nasopharyngeal carcinoma (NPC) is endemic in Southern China, and the prognosis of this cancer has improved in part due to advances in radiotherapy (RT) techniques, broadened therapeutic options, and more precise prognostic stratification of patients. RT is the primary curative treatment of NPC, and the incorporation of chemotherapy (induction, concurrent, adjuvant) to RT has contributed to improved survival in patients with locoregionally advanced NPC. Concurrent chemoradiotherapy (CCRT) in combination with adjuvant or induction chemotherapy is now the standard treatment of locoregionally advanced NPC, but the ideal CCRT therapeutic strategy for NPC remains controversial. Plasma EBV DNA is the archetypal tumor-derived DNA in NPC, and three generations of studies have gradually expanded its clinical applications. Recently, the advent of whole exome/genome sequencing of NPC and the promising clinical activity of immune checkpoint inhibitors have also spurred interest in the development of newer biomarkers. This review will focus on two clinical advances in NPC research that have made substantial impact on the contemporary management of NPC: (1) The integration of plasma EBV DNA in an expanding spectrum of clinical indications, and the development of promising immune-related biomarkers; (2) the current development of CCRT with special emphasis on the use of induction and adjuvant chemotherapy, as well as the potential applications of metronomic chemotherapy and immune checkpoint inhibitors in the treatment of locoregionally advanced NPC.

Cheadle E, M. Illidge T. Understanding the Effects of Radiotherapy on the Tumour Immune Microenvironment to Identify Potential Prognostic and Predictive Biomarkers of Radiotherapy Response

Radiotherapy (RT) is a highly effective anti-cancer treatment. Immunotherapy using immune checkpoint blockade (ICI) has emerged as a new and robust pillar in cancer therapy; however, the response rate to single agent ICI is low whilst toxicity remains. Radiotherapy has been shown to have local and systemic immunomodulatory effects. Therefore, combining RT and immunotherapy is a rational approach to enhance anti-tumour immune responses. However, the immunomodulatory effects of RT can be both immunostimulatory or immunosuppressive and may be different across different tumour types and patients. Therefore, there is an urgent medical need to establish biomarkers to guide clinical decision making in predicting responses or in patient selection for RT-based combination treatments. In this review, we summarize the immunological effects of RT on the tumour microenvironment and emerging biomarkers to help better understand the implications of these immunological changes, and we provide new insights into the potential for combination therapies with RT and immunotherapy.

Predictive Value of CD8 Expression and FoxP3 Methylation in Nasopharyngeal Carcinoma Patients Treated with Chemoradiotherapy in a Non-endemic Area

Undifferentiated Nasopharyngeal Carcinoma (UNPC) is associated with Epstein-Barr Virus (EBV) and characterized by an abundant immune infiltrate potentially influencing the prognosis. Thus, we retrospectively assessed the significance of immunosuppression in the UNPC microenvironment as prognostic biomarker of treatment failure in a non-endemic area, and monitored the variation of systemic EBV-specific immunity before and after chemoradiotherapy (CRT). DNA and RNA were extracted from diagnostic biopsies obtained by tumor and adjacent mucosa from 63 consecutive EBV+ UNPC patients who underwent radical CRT. Among these patients 11 relapsed within 2 years. The expression of the EBV-derived UNPC-specific BARF1 gene and several immune-related genes was monitored through quantitative RT-PCR and methylation-specific PCR analyses. Peripheral T cell responses against EBV and BARF1 were measured in 14 patients (7 relapses) through IFN-γ ELISPOT assay. We found significantly higher expression levels of BARF1, CD8, IFN-γ, IDO, PD-L1, and PD-1 in UNPC samples compared to healthy tissues. CD8 expression was significantly reduced in both tumor and healthy tissues in UNPC patients who relapsed within two years. We observed a hypomethylated FOXP3 intron 1 exclusively in relapsed UNPC patients. Finally, we noticed a significant decrease in EBV- and BARF1-specific T-cells after CRT only in relapsing patients. Our data suggest that a high level of immunosuppression (low CD8, hypomethylated FoxP3) in UNPC microenvironment may predict treatment failure and may allow an early identification of patients who could benefit from the addition of immune modulating strategies to improve first line CRT.

Long-term outcomes and safety after reirradiation in locally recurrent nasopharyngeal carcinoma in a non-endemic area

PURPOSE

To determine outcomes and toxicities after reirradiation for locally recurrent nasopharyngeal carcinoma (rNPC) and to apply a prognostic index in a non-endemic region.

METHODS

We retrospectively reported progression-free survival (PFS), overall survival (OS), and treatment-related toxicities in patients treated with curative intent for locally rNPC. We applied the prognostic model for OS and grade 5 radiotherapy (RT)-related toxicities published by Li et al. and evaluated its prognostic accuracy by receiver operating characteristic (ROC) curve analysis.

RESULTS

Between 2005 and 2018, 33 patients were treated for rNPC in our institution. Median follow-up was 60 months. The mean time to local recurrence was 75 months. Six (18%) patients had a persistent grade 3 toxicity from a previous RT course. The median re-RT dose was 66 Gy. After re-RT, 13 patients had local failure and 3 patients had metastatic recurrence. Median PFS was 18 months with a 5-year PFS rate of 29%. Median OS was 35 months with a 5-year OS rate of 37%. Grade 3 or higher toxicities rate was 74%. There were 21% grade 5 toxicities. The median time to a grade 5 toxicity was less than 6 months following re-RT. The prognostic nomogram was not predictive for OS or grade 5 toxicities.

CONCLUSION

Reirradiation of rNPC is an effective treatment but is associated with a high rate of life-threatening toxicity. Stratification of patients based on their risk of developing severe toxicity is needed to select patients who will most likely benefit from re-RT.

Immune checkpoint pathways in immunotherapy for head and neck squamous cell carcinoma

With the understanding of the complex interaction between the tumour microenvironment and immunotherapy, there is increasing interest in the role of immune regulators in the treatment of head and neck squamous cell carcinoma (HNSCC). Activation of T cells and immune checkpoint molecules is important for the immune response to cancers. Immune checkpoint molecules include cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed death 1 (PD-1), T-cell immunoglobulin mucin protein 3 (TIM-3), lymphocyte activation gene 3 (LAG-3), T cell immunoglobin and immunoreceptor tyrosine-based inhibitory motif (TIGIT), glucocorticoid-induced tumour necrosis factor receptor (GITR) and V-domain Ig suppressor of T cell activation (VISTA). Many clinical trials using checkpoint inhibitors, as both monotherapies and combination therapies, have been initiated targeting these immune checkpoint molecules. This review summarizes the functional mechanism and use of various immune checkpoint molecules in HNSCC, including monotherapies and combination therapies, and provides better treatment options for patients with HNSCC.

CD3+T-lymphocyte infiltration is an independent prognostic factor for advanced nasopharyngeal carcinoma

Background

Locally advanced nasopharyngeal carcinoma (LA-NPC) is a relatively rare disease in the west but more common in East Asia and areas of the Middle East like Saudi Arabia. Despite the advances in radiation therapy techniques, some patients relapse after treatment. In the coming era of cancer immunotherapy, prognostic factors for LA-NPC need to be further defined using immune-relevant markers. Several markers are available; however, the most robust and accessible/affordable marker is not well-defined.

Methods

Retrospectively, tumor-infiltrating lymphocytes (TIL), their subsets as well as tumoral PD-L1 expression were analyzed in tumor tissues from 63 LA-NPC patients treated with platinum-based concurrent chemo-radiotherapy (CCRT) in addition to 20 cases with metastatic (MET) disease. Immunostaining was done using a validated and fully automated system. Scoring was done by two independent pathologists and results were compared.

Results

There was no statistical difference between LA-NPC and MET disease in terms of CD3+, CD8+ TIL infiltration, or tumoral PD-L1 expression.

In LA-NPC, low CD3+ TIL infiltration highly correlated with shorter disease-free survival (DFS, HR = 8.5, p = < 0.001) and overall survival (OS, HR = 13, p = 0.015) with substantial agreement between scoring pathologists. A similar correlation was found between low CD8+ TIL and survival. Correlation of total TIL was significant with DFS (HR = 4.0, p = 0.008), borderline with OS and the correlation was dependent on the scoring pathologist. Having histological WHO type I&II correlated significantly with shorter DFS (HR 4.03, p = 0.008) and low CD3+ TIL (p = 0.009). Subgroup analysis of LA-NPC that included undifferentiated type (WHO type III) cases only (n = 58), showed a strong correlation between low CD3+ TIL and shorter DFS (HR = 7.2, p = < 0.001) and OS (HR = 17.3, p = 0.008). PD-L1 was expressed in 72% of type III LA-NPC cases while lacking PD-L1 expression correlated with shorter OS (HR = 6.1, p = 0.031). Patients with a combination of low CD3+ TIL and lack of PD-L1 expression had the worst OS (p < 0.001).

Conclusions

CD3+ TIL is promising as a robust and independent prognostic marker for DFS and OS of LA-NPC patients treated with platinum-based CCRT. We would suggest the use of CD3 + TIL as a stratifying factor for LA-NPC, which warrants further validation in prospective trials.

Tumor microenvironment predicts local tumor extensiveness in PD-L1 positive nasopharyngeal cancer

Tumor microenvironment have been implicated in many kind of cancers to hold an important role in determining treatment success especially with immunotherapy. In nasopharyngeal cancer, the prognostic role of this immune cells within tumor microenvironment is still doubtful. We conducted a study that included 25 nasopharyngeal cancer biopsy specimens to seek a more direct relationship between tumor infiltrating immune cells and tumor progression. Apart from that, we also checked the PD-L1 protein through immunohistochemistry. The PD-L1 was positively expressed in all our 25 samples with nasopharyngeal cancer WHO type 3 histology. Majority samples have >50% PD-L1 expression in tumor cells. We also found that denser local tumor infiltrating immune cells population have relatively much smaller local tumor volume. The inverse applied, with the mean local tumor volumes were 181.92 cm3 ± 81.45 cm3, 117.13 cm3 ± 88.72 cm3, and 55.13 cm3 ± 25.06 cm3 for mild, moderate, and heavy immune cells infiltration respectively (p = 0.013). Therefore, we concluded that tumor infiltrating immune cells play an important role in tumor progression, hence evaluating this simple and predictive factor may provide us with some valuable prognostic information.

The Prognostic Role of Programmed Death-Ligand 1 in Nasopharyngeal Carcinoma

OBJECTIVES

Programmed death-ligand 1 (PD-L1) is an immune checkpoint protein that may be a useful prognostic biomarker in nasopharyngeal cancer (NPC). The purpose of this systematic review and meta-analysis was to investigate the relationship between PD-L1 expression and survival in NPC.

METHODS

PubMed, Cochrane, Embase, Scopus, and Web of Science were searched from inception to present. A predefined inclusion and exclusion criteria were used to select articles. Hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled for overall survival (OS), disease-free survival (DFS), and disease metastasis-free survival (DMFS).

RESULTS

Eleven studies published from 2014 to 2018 were included, with 1,356 total participants. PD-L1 expression was not associated with OS (HR = 1.10, 95% CI: 0.79-1.55), DFS (HR = 1.66, 95% CI: 0.68-4.03), or DMFS (HR = 1.18, 95% CI: 0.44-3.20).

CONCLUSIONS

The prognostic role of PD-L1 in NPC remains unsubstantiated. Future research is needed. Laryngoscope, 130:2598-2606, 2020.

Current management of stage IV nasopharyngeal carcinoma without distant metastasis

Up to one in four patients with nasopharyngeal carcinoma present with non-metastatic stage IV disease (i.e. T4 or N3). Distinct failure patterns exist, despite the routine adoption of contemporary treatment modalities such as intensity modulated radiotherapy and systemic chemotherapy. Concurrent chemoradiotherapy (CCRT) followed by adjuvant chemotherapy or induction chemotherapy followed by CCRT are commonly employed in this setting, with the latter emerging as the preferred option. Additionally, emerging radiation technologies like proton therapy has become available offering new opportunities for prevention of radiation-induced side effects. This article reviews not only the current treatment strategies, but also discusses novel ways to tackle this challenging disease with respect to the patterns of failure.

PD-L1 Expression on Tumor Cells Is Associated With a Poor Outcome in a Cohort of Caucasian Nasopharyngeal Carcinoma Patients

Background: Nasopharyngeal carcinoma (NPC) is endemic in East Asia but rare in the western world. Programmed death ligand 1 (PD-L1) expression on NPC correlates with clinical outcomes. However, data for Caucasian NPC patients are missing. Thus, we performed this retrospective analysis for investigating the potential association of immune checkpoint protein expression with outcome parameters in Caucasian NPC patients.

Methods: Fifty-five patients with NPC treated between 1993 and 2018 at the Medical University of Vienna were identified. After the exclusion of Asian patients, data on baseline demographic, tumor stage, overall survival (OS), and disease-free survival (DFS) of 30 patients were analyzed. Their tumor samples were stained and scored (low vs. high) for PD-L1, programmed death receptor 1 (PD-1), lymphocyte activating gene 3 (LAG3), and cluster of differentiation 8 (CD8) antibodies. Statistical analysis was performed with Kaplan-Meier plots and log-rank test. Estimated hazard ratios of dichotomized analysis were calculated, together with 95% confidence intervals and p-values of Wald tests.

Results: PD-L1 expression was ≥50% in 6 (20%) patients, whereas 19 (63%) had ≥1% expression and 5 (17%) tumor samples were PD-L1-negative. While sex and age had no impact on DFS or OS, <50% PD-L1 expression on tumor cells (TC) was associated with a significantly longer OS (log rank test p = 0.037; HR 0.275; 95% CI 0.073–1.03). There was no influence on DFS (log rank test p = 0.34; HR 0.599; 95% CI 0.208–1.728). However, <10% PD-L1 expression on tumor infiltrating lymphocytes (TILs) was correlated with a worse DFS (log rank test p = 0.0057; HR 4.06; 95% CI 1.389–11.868). LAG3 expression or the number of TILs did not play any prognostic role in our population.

Conclusion: The PD-L1 expression rate on Caucasians was comparable to that in Asian patients. Although these results have to be interpreted with caution due to the limited number of Caucasian patients available, our data suggest that ≥50% PD-L1 expression on TC is associated with a poor outcome, while ≥10% PD-L1 expression on TILs is correlated with improved DFS. A prospective biomarker analysis of a predefined Caucasian NPC subpopulation would be desirable in future trials.

Expression and clinical significance of PD-L1 and BRAF expression in nasopharyngeal carcinoma

Background

The prognostic value of programmed death-ligand 1 (PD-L1) and BRAF expression in nasopharyngeal carcinoma (NPC) is not well-defined. In this study we investigated alterations in PD-L1, BRAF and EGFR by using immunohistochemistry analysis in a cohort of consecutively enrolled NPC patients.

Methods

A retrospective review of 154 NPC patients form our previous study (BMC Cancer. 2013; 13:226) were conducted. Survival and prognostic impacts were analyzed based on PD-L1, BRAF and EGFR expression levels.

Results

One hundred fifty four patients were included in this study. PD-L1 expression was detected in 87.7% of patients; 14.3% had 1–5% PD-L1 expression, 47.4% had 5–49% expression while 26% had ≥50% expression Higher PD-L1 expression was significantly associated with shorter PFS and OS. The median PFS was 25 months (95% CI 15.7–34.3 months) and OS was 35 months (95% CI 22.60–47.4 months) for patients with PD-L1 expression ≥50%; both median PFS and OS were not yet reached for patients with PD-L1 expression < 50%. PFS was significantly higher in BRAF mutation positive patients (5-year PFS: 55.1% vs. 30.8%, P = 0.044).

Conclusion

Tumor PD-L1 expression and BRAF mutation are associated with poor outcomes in patients with NPC. This study was retrospectively registered in ClinicalTrials.gov (NCT03989297) on 2019-6-18.

Prognostic Value of Programmed Cell Death Ligand-1 Expression in Nasopharyngeal Carcinoma: A Meta-Analysis of 1,315 Patients

Background: The prognostic value of programmed cell death ligand-1 (PD-L1) in patients with nasopharyngeal carcinoma (NPC) remains controversial. Therefore, we conducted this meta-analysis to understand the role of PD-L1 in NPC.

Method: We searched PubMed, Embase, Web of Science, and Cochrane Library up to April 2019. We determined the pooled hazard ratio (HR) and 95% confidence intervals (CIs) to assess the relationship between PD-L1 and various survival outcomes. Begg's funnel plot was used to assess any publication bias.

Results: Eleven studies involving 1,315 patients were included in this meta-analysis. For overall survival (OS), the HR was 1.48 and 95% CI was 1.00–2.18 (p = 0.049). For disease-free survival (DFS), the HR was 1.51 and 95% CI was 0.85–2.69 (p = 0.162). For distant metastasis-free survival (DMFS), the HR was 1.75 and 95% CI was 0.64–4.79 (p = 0.277). For local recurrence-free survival (LRFS), the HR was 0.67 and 95% CI was 0.06–8.16 (p = 0.756). The results of prognosis of PD-L1 and OS were more significant after sensitivity analysis. The pooled odds ratio indicated that PD-L1 expression was not associated with T stage, N stage, M stage, overall stage, sex, age, smoking, or alcohol intake. No publication bias was found.

Conclusion: Our meta-analysis showed that PD-L1 overexpression in NPC was associated with a poor OS and may be useful as a novel prognostic factor for NPC.

PD-1 high expression predicts lower local disease control in stage IV M0 nasopharyngeal carcinoma

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) play a critical role in tumor immune surveillance and immune suppression. Understanding tumor infiltrating T cell subset density, location and PD-1/PD-L1 expression might provide insight for the prediction of tumor therapeutic response and clinical outcome. The purpose of this study was to evaluate the expression and localization of CD8, FoxP3, PD-1, and PD-L1 in primary tumor tissues and their effects on prognosis of stage IV M0 locally advanced nasopharyngeal carcinoma (NPC) patients.

METHODS

Sixty NPC patients with stage IV M0 locally advanced disease were treated with definitive chemoradiation. Tumor biopsies from primary lesion were analyzed for the expression and localization of CD8, FoxP3, PD-1, and PD-L1 by immunohistochemistry. Their associations with local disease control and survival of NPC were analyzed.

RESULTS

The average follow-up time was 43 months (range from 14 to 61 months). High expression of CD8^+, FoxP3⁺, PD-1⁺ and PD-L1⁺ was observed in 60, 86.7, 56.7, and 91.7% of patients, respectively. There was no correlation between clinicopathological features and the expression of these immune markers. High PD-1 expression was found to be associated with lower local disease control (5-year LRFS 23.2% vs 96.8%, p < 0.001) and unfavorable clinical outcome (5-year OS 47.4% vs 73.3%, p = 0.014). In multivariate analysis, PD-1 expression was also an adverse prognostic factor for 5-year OS (HR: 3.68, P = 0.023) and LRFS (HR: 16.89, 1.27-11.84, P = 0.007). Those with PD-1 distribution in both stroma and tumor region had the poorest prognosis. However, PD-1 expression has no significant correlation with 5-year RRFS (p = 0.980) and DMFS (p = 0.865). Patients with both PD-1 and PD-L1 high expression had significant poor local disease control (5-year LRFS 96.0% vs 43.0%, p < 0.001) and overall survival (5-year OS 80.8% vs 45.1%, p < 0.001) compared with the others. Other immune markers were not found having corrections with disease control and survival.

CONCLUSIONS

PD-1 high expression, especially with PD-L1 co-expression, is associated with high local recurrence and unfavorable clinical outcome for stage IV M0 NPC patients, and might be a potential target for immunotherapy.

The prognostic significance of PD-L1 and PD-1 expression in patients with nasopharyngeal carcinoma: a systematic review and meta-analysis

Background

Whether PD-L1/PD-1 expression plays a significant role in the prognosis of NPC is still controversial. The present study mainly aimed to investigate the prognostic significance of PD-L1/PD-1 expression in patients with NPC.

Methods

A systematical research was performed in the PubMed, Web of Science, EMBASE, and the Cochrane Library databases up to January 06, 2019. Eighteen studies met eligible criteria were included in the meta-analysis. Quality assessment of included articles was evaluated by Newcastle–Ottawa quality assessment scale (NOS). Pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were used to elucidated the primary endpoint, overall survival (OS), and the secondary endpoints. Furthermore, the relationship between clinicopathological features of NPC and PD-L1/PD-1 expression was estimated by relative ratios (RRs) and 95% CIs.

Results

A total of 1836 patients from 15 included studies concerning PD-L1 and 678 patients from six studies regarding PD-1 were included in the meta-analysis. Pooled results revealed that PD-L1 expression in NPC did not correlate with OS (HR 1.34 95% CI 0.93–1.93, p = 0.11), DFS (HR 1.82, 95% CI 0.86–3.85, p = 0.12), PFS (HR 1.19, 95% CI 0.46–3.08, p = 0.72), and DMFS (HR 2.26, 95% CI 0.60–8.56, p = 0.23). Meanwhile, no statistically significant differences existed between the expression level of PD-1 in tumor infiltrating lymphocytes (TILs) and the OS in NPC, with the pooled HR 1.29 (95% CI 0.68–2.42, p = 0.44). In subgroup analysis, higher expression of PD-L1 in immune cells correlated with better OS in patients with NPC, with a pooled HR 0.68 (95% CI 0.47–0.99, p = 0.04). Among the clinicopathological features included in our study, we found that the positive expression of PD-L1 in NPC associated with the higher expression of PD-1 (RR 1.25, 95% CI 1.02–1.52, p = 0.03).

Conclusions

Our meta-analysis indicated that higher/positive expression of PD-L1/PD-1 may not serve as suitable biomarkers for the prognosis of NPC, which was not in consistent with some previous studies about the prognostic value of PD-L1/PD-1 in other types of tumors. Despite the positive results in subgroup analysis and study about clinicopathological features, it may still need corroboration of prospective and large-scale studies.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0863-5) contains supplementary material, which is available to authorized users.

Clinical relevance and significance of programmed death-ligand 1 expression, tumor-infiltrating lymphocytes, and p16 status in sinonasal squamous cell carcinoma

Purpose: Immunotherapy may be a potential alternative for patients with sinonasal squamous cell carcinoma (SNSCC). Data regarding potential immunotherapy targets, such as programmed death-ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs), in SNSCC are limited. In this study, we assessed the prevalence and prognostic value of PD-L1 expression and TILs in p16-negative and p16-positive SNSCC. Patients and methods: Tissues from 96 patients with SNSCC were stained using immunohistochemistry against PD-L1, CD8, and Foxp3 to assess the immune environment. The correlations between PD-L1 expression, TILs, and p16 status were analyzed. Additionally, PD-L1, CD8, and Foxp3 expressions, as well as p16 status, were analyzed in relation to patient clinicopathological variables and prognosis. Results: Twenty-nine (30.2%) patients with SNSCC showed PD-L1 expression in >5% of tumor cells. PD-L1 expression was significantly correlated with poor differentiation and a high level of TILs. PD-L1 expression and the CD8+ and Foxp3+ T-cell infiltrates in p16-negative patients (n=78, 81.2%) and p16-positive patients (n=18, 18.8%) were not significantly different. PD-L1 expression and p16 status were not associated with overall survival (OS) and disease-free survival (DFS). Patients with high CD8+ or Foxp3+ cell infiltration had better clinical outcomes. A multivariate analysis confirmed that CD8 TILs were a significant independent and favorable prognostic factor for OS (p=0.023) and DFS (p=0.008). Conclusion: TILs can play a prognostic role in SNSCC. We did not find differences in immune marker expression between p16-positive and p16-negative SNSCC tissues. The high correlation between PD-L1 expression and TILs indicates that the PD-1/PD-L1 pathway is a promising immunotherapeutic target for SNSCC.

Mismatch repair status and high expression of PD-L1 in nasopharyngeal carcinoma

Purpose

To analyze the mismatch repair (MMR) status and PD-L1 expression in nasopharyngeal carcinoma (NPC), and investigate whether PD-L1 and MMR status could be used as a biomarker for predicting response of immune checkpoint blockades (ICBs) treatment.

Patients and methods

A total of 108 patients were initially histopathologically diagnosed with NPC between December 2017 and September 2018. All tissue specimens were collected before any treatment. Tumor tissue MMR status was determined by both immunohistochemistry and PCR. The expression of PD-L1 in NPC tissue was analyzed immunohistochemically. High PD-L1 expression in tumor cells (TC) or tumor-infiltrating immune cells (TIIC) was defined as ≥50% of corresponding cells with membranous staining.

Results

Tissue samples were obtained from 102 patients after written informed consent was obtained. Seventy-one (69.6%) patients were treated in our hospital after diagnosis. Disease in stages I-III accounted for 35 (49.3%) cases, while stage IVa-IVb was identified in 36 (50.7%) cases. Only two of 102 patients were identified as MMR-deficient (dMMR) by IHC and PCR. High PD-L1 expression in TC was confirmed in 77 of the 102 (75.5%) NPC cases, while only 13 of the 102 (12.7%) NPC cases were considered to exhibit high PD-L1 expression in TIIC. PD-L1 expression in TC was positively correlated with T stage (P=0.033), while PD-L1 expression in TIIC was negatively associated with plasma Epstein-Barr virus DNA load (P=0.021), N stage (P=0.009), M stage (P=0.014), and clinical stage (P=0.001).

Conclusion

dMMR is a rare event in NPC and may not be a prospective biomarker to predict the effectiveness of treatment with ICBs in clinical practice. It was also determined that high PD-L1 expression in NPC is quite common and the importance of distinguishing PD-L1 expression in TC and TIIC was highlighted.

Prognostic value of immune checkpoint molecules in head and neck cancer: a meta-analysis

Immune checkpoint molecules are important targets in cancer immunotherapy, but their association with prognosis in patients with head and neck cancer is controversial. In this meta-analysis, we searched for 12 immune checkpoint molecules in the PubMed, Embase and Cochrane Library databases and retrieved 52 studies with 7127 participants. Among the molecules included in the search, indoleamine 2, 3-dioxygenase (IDO), programmed death ligand 1 (PD-L1), and programmed death 1 (PD-1) met the inclusion criteria for further analysis. Higher expression of IDO was associated with poorer overall survival in head and neck cancer patients (P = 0.011), but higher expression of PD-L1 correlated with better overall survival specifically in nasopharyngeal carcinoma patients (P = 0.01). In a sensitivity analysis, higher PD-L1 expression correlated with better progression-free survival (P = 0.043), and was associated with better overall survival in Caucasian subjects (P = 0.02), nasopharyngeal carcinoma patients (P = 0.015), and studies with small sample sizes (P = 0.001). PD-1 had no prognostic significance. There was no publication bias affecting the results. Thus, among the immune checkpoint molecules, IDO and PD-L1 are potential prognostic predictors in head and neck cancer.

PD-1 and PD-L1 in locoregionally advanced nasopharyngeal carcinoma: Substudy of a randomized phase III trial

BACKGROUND

To evaluate the expression of programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) by using immunohistochemistry analysis in locoregionally advanced nasopharyngeal carcinoma (NPC) patients receiving cisplatin, fluorouracil, and docetaxel followed by concurrent chemoradiotherapy.

METHODS

As part of a previously reported trial, 108 patients were enrolled in this study.

RESULTS

We observed that Epstein-Barr Virus (EBV) antibody levels were associated with PD-1 positive staining in NPC and PD-1 positive staining was identified as an independent prognostic factor for progression-free survival (hazard ratio 0.363, 95% confidence interval 0.134-0.987, P = .047). By contrast, the correlation between the PD-L1 level and hemoglobin, lactate dehydrogenase and high-sensitivity C-reactive protein was not identified. Moreover, high levels of PD-L1 staining were not significantly associated with clinical outcomes.

CONCLUSION

NPC patients with negative PD-1 staining had a significantly reduced survival outcome. Furthermore, patients with positive PD-1 staining had significantly higher EBV antibody levels.

Low PD-L1 Expression Strongly Correlates with Local Recurrence in Epstein-Barr Virus-Positive Nasopharyngeal Carcinoma after Radiation-Based Therapy

The prognostic value of programmed death-ligand 1 (PD-L1) expression in nasopharyngeal carcinoma (NPC) is controversial, with previous studies showing conflicting results. Most NPCs in endemic areas are Epstein-Barr virus (EBV)-positive. Our aim was to evaluate the clinical significance of PD-L1 expression in EBV-positive NPC. We retrospectively analyzed PD-L1 expression on tumor cells (TCs) and immune cells (ICs) by immunohistochemistry in 208 EBV-positive NPC patients who underwent radiotherapy (203 with concurrent chemotherapy). The percentages of TCs and ICs expressing PD-L1 were evaluated respectively. There was a strong correlation between local recurrence and low PD-L1 expression on ICs (p = 0.0012), TCs (p = 0.013) or both (p = 0.000044), whereas all clinical parameters had no influence on local recurrence. Using multivariate analysis, low PD-L1 expression on ICs was an independent adverse prognostic factor (p = 0.0080; HR = 1.88; 95% CI = 1.18⁻3.00) for disease-free survival. High PD-L1 expression on both ICs and TCs was an independent favorable prognostic factor (p = 0.022; HR = 0.46; 95% CI = 0.24⁻0.89) for overall survival. We show for the first time that low PD-L1 expression on ICs and TCs strongly correlates with local recurrence in EBV-positive NPC patients after radiation-based therapy. A simple immunohistochemical study for PD-L1 can identify patients prone to local recurrence, and such patients might benefit from more aggressive treatment in future clinical trials.

Immunotherapy in head and neck cancers: A new challenge for immunologists, pathologists and clinicians

Cancer occurrence can be understood as the result of dysfunctions in immune tumoral microenvironment. Here we review the recent understandings of those microenvironment changes, regarding their causes and prognostic significance in head and neck (HN) carcinoma. We will focus on HN squamous cell cancer (SCC) and nasopharyngeal carcinomas (NPC). Their overall poor prognosis may be improved with immunotherapy in a subset of patients, as supported by current clinical trials. However, finding reliable markers of therapeutic response is crucial for patient selection, due to potential severe adverse reactions and high costs. Half of HNSCC exhibit PD-L1 expression, this expression being higher in HPV-positive tumors. In recent clinical trials, a better therapeutic response to anti-PD-1 was obtained in patients with higher PD-L1 expression. The Food and Drug Administration (FDA) approved the use of these therapeutics without stating a need for patient selection regarding PD-L1 status. Activation status, density and localization of TIL as well as PD-L2, γ-interferon, inflammatory cytokines, epithelial-mesenchymal transition phenotype and mutational burden may all be potential therapeutic response markers. In Epstein-Barr Virus (EBV)-induced nasopharyngeal non-keratinizing cancer, PD-L1 is over-expressed compared to EBV-negative tumors. A 22% response rate has been observed under anti-PD-1 treatment among PD-L1-positive NPC patients. A better understanding of immune checkpoint regulation processes may allow patients to benefit from these promising immunotherapies.

Programmed death ligand 1 expression in esophageal cancer following definitive chemoradiotherapy: Prognostic significance and association with inflammatory biomarkers

Immunotherapy with anti-programmed cell death protein 1 or programmed death ligand 1 (PD-L1) agents has demonstrated promising efficacy for the treatment of various types of malignancies. However, the role of PD-L1 as a tumor prognostic marker remains poorly understood. In the present study, the prognostic value of PD-L1 expression in esophageal carcinoma (EC) following definitive chemoradiotherapy (CRT) was investigated, and its associations with three systemic inflammation biomarkers, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) were further explored. A total of 104 patients with non-metastatic EC, who underwent definitive CRT between January 2009 and December 2012, were retrospectively analyzed. The expression of PD-L1 was examined by immunohistochemistry and the impact of PD-L1 expression level on overall survival (OS) was assessed. Furthermore, pretreatment neutrophil, lymphocyte, platelet and monocyte counts were obtained from routine blood tests to calculate the NLR, PLR and LMR. PD-L1 was overexpressed in EC compared with normal esophageal epithelium, with a positive expression rate of 37.5%. Additionally, patients with positive PD-L1 expression had a lower NLR than those with negative PD-L1 expression (P=0.001). On multivariate analysis, the positive staining of PD-L1 was significantly associated with improved OS (HR, 0.6; 95% CI, 0.372–0.965; P=0.035). Kaplan-Meier survival analysis showed a similar result (P=0.009). Additionally, sex (HR, 0.449; 95% CI, 0.229–0.880; P=0.020), clinical stage III (HR, 2.471; 95% CI, 1.171–5.212; P=0.018), and receipt of concurrent chemoradiation (HR, 0.590; 95% CI, 0.368–0.945; P=0.028) were all independent prognostic factors in EC treated with definitive CRT. The correlation of NLR with PD-L1 expression validated the relevance of immunity and inflammation. In summary, the present study demonstrated that positive PD-L1 expression is associated with improved survival in patients with EC treated with radical CRT, indicating that PD-L1 is a promising prognostic marker.

Cytomembranic PD-L1 expression in locoregionally advanced nasopharyngeal carcinoma

Background and objective

The aim of this study was to evaluate the expression of cytomembranic programmed death-ligand 1 (PD-L1) and its clinical significance in locoregionally advanced nasopharyngeal carcinoma (NPC).

Patients and methods

Formalin-fixed, paraffin-embedded tissue biopsies from 85 patients with histological diagnosis of locoregionally advanced NPC treated with radical intensity-modulated radiotherapy and concurrent cisplatin-based chemotherapy were studied. By using immunohistochemistry staining, expressions of cytomembranic PD-L1 on tumor cells were detected.

Results

After a median follow-up duration of 65.8 months, 7 (8.2%), 5 (5.9%), and 5 (5.9%) patients suffered from local failure, regional failure, and distant metastases, respectively. The 5-year local failure-free survival, regional failure-free survival, distant failure-free survival, and overall survival (OS) rates were 90.9%, 94.8%, 94.0%, and 92.2%, respectively. Our results revealed that a high expression of cytomembranic PD-L1 was correlated with shorter OS (5y-OS: 82.5% vs 97.6%, P=0.022). In the multivariate analysis, only the cytomembranic PD-L1 was an independent prognostic factor for OS (hazard ratio: 6.176, 95% confidence interval, 1.166–32.710, P=0.032).

Conclusion

Cytomembranic PD-L1 expression levels correlated with OS in locoregionally advanced NPC. Agreement between different methods is needed for further application of PD-L1 biomarker assays in NPC.

Prognostic value of programmed cell death ligand 1 expression in patients with head and neck cancer: A systematic review and meta-analysis

Background

Programmed cell death ligand 1 (PD-L1) expression was reported to be correlated with poor prognosis in various cancers. However, the relationship between PD-L1 expression and the survival of patients with head and neck cancer (HNC) remains inconclusive. In the present study, we aimed to clarify the prognostic value of PD-L1 in HNC patients using meta-analysis techniques.

Methods

A comprehensive database searching was conducted in the PubMed, EMBASE, Web of Science and Cochrane Library from inception to August 2016. Studies meeting the inclusion criteria were included. The methodological quality of included studies was assessed by the Newcastle-Ottawa quality assessment scale. Hazard ratios (HRs) with their corresponding 95% confidence intervals (CIs) were pooled by STATA 11.0 for the outcome of overall survival (OS) and disease-free survival (DFS).

Results

A total of 17 studies with 2,869 HNC patients were included in the meta-analysis. The results of meta-analysis showed that there was no significant correlation between PD-L1 expression and OS (HR, 1.23; 95% CI, 0.99–1.53; P = 0.065) or DFS (HR, 1.42; 95% CI, 1.00–2.03; P = 0.052) of HNC patients. However, the subgroup analysis suggested that positive expression of PD-L1 was associated with poor OS (HR, 1.38; 95% CI, 1.12, 1.70; P = 0.003) and DFS (HR, 1.99; 95% CI, 1.59, 2.48; P = 0.001) in HNC patients from Asian countries/regions. The subgroup analysis also showed that the correlations between PD-L1 and prognosis are variant among different subtypes of HNC. When performing sensitive analyses, we found that the results of meta-analyses were not robust.

Conclusion

The meta-analysis indicated that positive expression of PD-L1 could serve as a good predictor for poor prognosis of Asian patients with HNC. However, the findings still need to be confirmed by large-scale, prospective studies.

PD-1 and PD-L1 expression in 132 recurrent nasopharyngeal carcinoma: the correlation with anemia and outcomes

The expression of Programmed death-1 (PD-1) / programmed death-ligand 1 (PD-L1) has been reported to be reliable prognostic factors in various malignances including primary nasopharyngeal carcinoma (NPC). However, the exact role of PD-1/PD-L1 in recurrent NPC remains unclear. In this study, we aimed to investigate the relationship between the expression of PD-1 / PD-L1 and the clinical-pathology as well the outcomes of recurrent NPC patients (n = 132). The expression of PD-1 and PD-L1 was measured by immunohistochemistry staining. The relationship between PD-1 / PD-L1 and factors involved in clinic-pathology and outcomes of patients with NPC was assessed by correlation analysis. To further explore the association between PD-L1 and anemia, immunofluorescence analysis was performed to investigate the correlation of PD-L1 with hypoxia inducible factor-1α (HIF-1α). We observed that advanced rT classification and anemia status before salvage treatment was associated with high level of PD-L1 in recurrent NPC patients, and PD-L1 and was co-located with HIF-1α in recurrent tumors by immunofluorescence analysis. Moreover, our result suggested that PD-L1 might be a negative indicator for recurrent NPC patients as well as age, rT classification, anemia and tumor necrosis at diagnose of recurrence. Taken together, our results revealed that PD-L1 might be a potential prognostic biomarker for recurrent NPC patients, and advanced re-stage, anemia might represent as candidate biomarkers for evaluating patients’ response to anti-PD-1 / PD-L1-treatment. However, further studies are needed to clarify the underlying mechanism of hypoxia in immunosuppression process induced by PD-1 / PD-L1 axis.

PD-L1 predicts poor prognosis for nasopharyngeal carcinoma irrespective of PD-1 and EBV-DNA load

Programmed death-1 (PD-1) is an immunosuppressive receptor functionally bound with programmed death-ligand 1 (PD-L1), which has been reported in various malignancies. However, only a few studies are available for the clinical significance of PD-1/PD-L1 in nasopharyngeal carcinoma (NPC). In this study, we aim to investigate alterations in PD-1/PD-L1 by using immunohistochemistry analysis in a cohort of consecutively enrolled NPC patients (n = 99). To further analyse the correlation between PD-1/PD-L1 and factors involved in clinico-pathology, haematologic biomarkers, EBV-DNA load and outcomes, we collected clinical data for statistical analysis. We observed that lower haemoglobin (HB) and Body Mass Index (BMI) levels were associated with high levels of PD-L1 staining in NPC patients. Importantly, our results suggested that PD-L1 might be a negative indicator for NPC patients. In contrast, a correlation between the PD-1/PD-L1 level and EBV load was not identified. Moreover, PD-1 positivity was suggested to not be significantly correlated with clinical outcomes. Taken together, our results revealed that PD-L1 might be a potential prognostic biomarker for NPC patients. However, further studies are needed to clarify the underlying mechanism of EBV status in the immunosuppression process induced by the PD-1/PD-L1 axis.

Programmed Death-Ligand 1 Expression, Microsatellite Instability, Epstein-Barr Virus, and Human Papillomavirus in Nasopharyngeal Carcinomas of Patients from the Philippines

Most nasopharyngeal carcinomas (NPCs) in a high-incidence population are driven by Epstein-Barr virus (EBV) infection. EBV-associated malignancies have increased expression of the programmed death-ligand 1 (PD-L1). Immunotherapy agents targeting the PD-1/PD-L1 pathway have achieved durable treatment effects in patients with various cancer types including EBV-associated malignancies. In this study, we sought to investigate PD-L1 expression in a cohort of patients with NPCs from the Philippines. Fifty-six NPCs were studied for PD-L1, p16, and DNA mismatch repair (MMR) deficiency by immunohistochemistry. One case with MMR deficiency was also assessed for microsatellite instability (MSI) by polymerase chain reaction. EBV and human papillomavirus (HPV) status were tested by in situ hybridization. All NPCs were p16 negative. Three of the 56 NPCs (5%) were EBV negative (EBV-) and HPV negative, while one NPC (1/56, 2%) was EBV positive and showed MSI (EBV+/MSI). Positive PD-L1 expression (PD-L1+), defined as membranous staining in ≥1% tumor cells, was seen in 64% (36/56) of NPCs. All three EBV- NPCs were PD-L1+ as was the EBV+/MSI NPC. PD-L1+ was seen significantly more often in NPCs from non-smokers than those from smokers (23/28, 82% vs 9/18, 50%; P = 0.047). PD-L1+ was not associated with pT, pN, distant metastasis, or clinical stage (P > 0.05). PD-L1+ was not associated with overall survival (P = 0.473). In summary, our results show frequent PD-L1 expression in NPCs regardless of EBV status and a preferential PD-L1 expression in non-smokers. MSI and HPV positivity are exceedingly rare in NPCs.