Prognostic value of plasma Epstein-Barr virus DNA level during posttreatment follow-up in the patients with nasopharyngeal carcinoma having undergone intensity-modulated radiotherapy

Comparison of Epstein-Barr virus copy number in white blood cells of chronic lymphocytic leukemia patients with laboratory prognostic biomarker

BACKGROUND AND OBJECTIVE

The DNA load of EBV may play a part in CLL pathogenesis and prognosis. The objective of this cross-sectional study was to examine the prognostic value of EBV viral load in CLL patients in comparison with other common laboratory prognostic factors.

MATERIALS AND METHODS

Whole blood and sera from forty untreated CLL patients were collected. Next, DNA was extracted from total white blood cells (WBC), and TaqMan real-time PCR was performed to determine the EBV-DNA load by amplifying a specific fragment in the BNRF1 gene. In addition, parameters such as complete blood counts (CBC) and lactate dehydrogenase (LDH) were determined using an automated clinical laboratory analyzer.

RESULTS

Twenty-one patients (52.5%) were positive for EBV by real-time PCR analysis (ranged 20 to 30000 copies/µL). The difference in LDH mean levels between EBV positive and negative patients was marginally significant (P = 0.05). Furthermore, platelet (PLT) count (P = 0.03) and CD5+/CD19+ count (P = 0.04), between EBV positive and negative subgroups, were substantially different. In addition, individuals with a severe form of illness, as defined by an increase in LDH, a decrease in PLT, and an 11q deletion, had considerably higher EBV-DNA copy numbers (the ranges of viral loads were 9966.66 ± 20033 in the severe form vs. 137.13 ± 245.41 in the mild form).

CONCLUSION

The EBV-DNA load could be used as a prognostic factor in the initial examination of CLL patients to better characterize the disease outcome and prognosis.

A magnetic resonance imaging-based lymph node regression grading scheme for nasopharyngeal carcinoma after radiotherapy

Background

Among patients with nasopharyngeal carcinoma (NPC), there is no established method to distinguish between patients with residual disease that may eventually progress and those who have achieved cured. We thus aimed to assess the prognostic value of magnetic resonance imaging (MRI)-based lymph node regression grade (LRG) in the risk stratification of patients with NPC following radiotherapy (RT).

Methods

This study retrospectively enrolled 387 patients newly diagnosed with NPC between January 2010 and January 2013. A four-category MRI-LRG system based on the areal analysis of RT-induced fibrosis and residual tumor was established. Univariate analysis was performed using the Kaplan-Meier method, and comparisons were conducted via the log-rank test. Multivariate analyses were conducted using Cox regression models to calculate the hazard ratios (HRs) with 95% confidence intervals (CIs) and adjusted P values. Survival curves were calculated using the Kaplan-Meier method and compared using the log-rank test.

Results

The sum of MRI-LRG scores (LRG-sum) was an independent prognostic factor for progression-free survival (PFS) (HR 2.50, 95% CI: 1.28-4.90; P<0.001). LRG-sum ≤9 and >9 showed a poorer 5-year PFS rate than did LRG-sum ≤2 (66.1%, 42.9%, and 77.6%, respectively; P<0.001). A survival clustering analysis-based decision tree model showed more complex interactions among LRG-sum and pretreatment and post-RT Epstein-Barr virus (EBV) DNA, yielding four patient clusters with differentiated disease progression risks (5-year PFS rates of 89.5%, 76.4%, 57.6%, and 27.8%, respectively), which showed better risk stratification than did post-RT EBV DNA alone (P<0.001).

Conclusions

The MRI-LRG system adds prognostic information and is a potentially reliable, noninvasive means to stratify treatment modalities for patients with NPC.

Combining Transoral Nasopharyngeal Brush and Plasma Epstein-Barr Virus DNA in Detecting Locally Recurrent Nasopharyngeal Carcinoma

OBJECTIVE

To evaluate the sensitivities and specificities of Epstein-Barr virus (EBV) DNA in the detection of locally recurrent or persistent nasopharyngeal carcinoma (NPC) through nasopharyngeal (NP) brush biopsy and plasma, respectively, and whether a combination of both would be superior to the individual tests.

STUDY DESIGN

A case-control study was conducted from September 2016 to June 2022.

SETTING

A multicentre study at 3 tertiary referral centers in Hong Kong was conducted by the Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong.

METHODS

Twenty-seven patients with biopsy-confirmed locally recurrent NPC were recruited as study subjects. Magnetic resonance imaging was performed to rule out regional recurrence. The control group consisted of 58 patients with a prior history of NPC who were now disease-free based on endoscopic and imaging findings. Patients underwent both the transoral NP brush (NP Screen®) and blood for plasma Epstein-Barr DNA levels.

RESULTS

The sensitivity and specificity of the combined modalities were 84.62% and 85.19%, respectively. The positive predictive value was 73.33% and the negative predictive value was 92.0%.

CONCLUSION

The combination of NP brush biopsy and plasma EBV DNA is potentially an additional surveillance modality in detecting the local recurrence of NPC. Further study with a larger sample size would be required to validate the cutoff values.

CRISPR Cas12a-mediated amplification-free digital DNA assay improves the diagnosis and surveillance of Nasopharyngeal carcinoma

Sensitive and accurate cell-free plasma Epstein-Barr virus (EBV) DNA measurement is essential in the routine diagnosis, monitoring and treatment of Nasopharyngeal Carcinoma (NPC). This measurement in commercial and in-house assay are commonly based on real-time quantitative PCR (qPCR) method, which requires reference materials for standardization and lack quantitative precision due to amplification bias or cross-contamination. To address these issues, we developed a CRISPR/Cas12a-mediated amplification-free digital DNA assay, which targets the repetitive sequences of EBV DNA and utilizes the cis-cleavage activity of CRISPR-Cas12a prior to droplet generation. By this mean, more activated Cas12a-crRNA duplexes could be produced for subsequent target detection and counting, thus improving the performance in detecting low EBV DNA load. We demonstrated that it was more robust than conventional qPCR for detecting plasma EBV DNA in a case-control study of 208 participants, especially when the target concentrations were around the diagnostic cut-off value for NPC. More importantly, this assay allowed a more accurate diagnosis of early-stage NPC, with an area under the curve (AUC) of 0.9883 (versus 0.7682 for qPCR). Furthermore, its absolute quantification capability enabled dynamic monitoring of EBV load in NPC patients during initial diagnosis, treatment, and recurrence, thereby potentially improving disease management and prognosis. Taken together, our results demonstrate that this amplification-free digital assay has the potential to be a robust tool to improve the diagnosis and surveillance of NPC.

Sodium Butyrate Induces Mitophagy and Apoptosis of Bovine Skeletal Muscle Satellite Cells through the Mammalian Target of Rapamycin Signaling Pathway

Sodium butyrate (NaB) is one of the short-chain fatty acids and is notably produced in large amounts from dietary fiber in the gut. Recent evidence suggests that NaB induces cell proliferation and apoptosis. Skeletal muscle is rich in plenty of mitochondrial. However, it is unclear how NaB acts on host muscle cells and whether it is involved in mitochondria-related functions in myocytes. The present study aimed to investigate the role of NaB treatment on the proliferation, apoptosis, and mitophagy of bovine skeletal muscle satellite cells (BSCs). The results showed that NaB inhibited proliferation, promoted apoptosis of BSCs, and promoted mitophagy in a time- and dose-dependent manner in BSCs. In addition, 1 mM NaB increased the mitochondrial ROS level, decreased the mitochondrial membrane potential (MMP), increased the number of autophagic vesicles in mitochondria, and increased the mitochondrial DNA (mtDNA) and ATP level. The effects of the mTOR pathway on BSCs were investigated. The results showed that 1 mM NaB inhibited the mRNA and protein expression of mTOR and genes AKT1, FOXO1, and EIF4EBP1 in the mTOR signaling pathway. In contrast, the addition of PP242, an inhibitor of the mTOR signaling pathway also inhibited mRNA and protein expression levels of mTOR, AKT1, FOXO1, and EIF4EBP1 and promoted mitophagy and apoptosis, which were consistent with the effect of NaB treatment. NaB might promote mitophagy and apoptosis in BSCs by inhibiting the mTOR signaling pathway. Our results would expand the knowledge of sodium butyrate on bovine skeletal muscle cell state and mitochondrial function.

Early Stage and Locally Advanced Nasopharyngeal Carcinoma Treatment from Present to Future: Where Are We and Where Are We Going?

OPINION STATEMENT

Nasopharyngeal carcinoma (NPC) is a rare malignancy, endemic in China, that is commonly diagnosed in locally advanced scenarios. Its pathogenesis is strongly associated with Epstein-Barr virus (EBV), an infection for which measuring EBV plasma DNA levels has helped as a prognostic factor guiding treatment options, including a stronger treatment in those with high titers. Additionally, tobacco and alcohol are often implicated in EBV-negative patients. The local disease is treated with radiotherapy alone, preferentially intensity modulated radiotherapy. For locally advanced disease, the backbone treatment is concurrent chemoradiotherapy with the ongoing research dilemma being adding adjuvant chemotherapy or induction chemotherapy. The ongoing research is focused not only on identifying patients that will benefit from adjuvant or induction chemotherapy, but also on identifying the best chemotherapeutic regimen, regimen alternatives to diminish toxicity, the role that immune checkpoint inhibitors play, and the use of molecularly guided treatment targeting patients with NPC whether driven by EBV or tobacco and alcohol. Knowing the precise oncogenesis of NPC not only offers a better understanding of the role that EBV plays in this tumor but also helps create targeted therapies that could potentially block important pathways such as the NF-κB pathway. Much is yet to be done, but the prognosis and management of NPC patients have changed drastically, offering precise treatment methods and excellent control of the disease, even in locally advanced scenarios.

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.

Thyroid dysfunction in Chinese nasopharyngeal carcinoma after anti-PD-1 therapy and its association with treatment response

BACKGROUND

Programmed cell death protein-1 (PD-1) blockade therapies have demonstrated efficacy in nasopharyngeal carcinoma (NPC). Thyroid dysfunction is among the most common immune-related adverse events. This study aimed to explore the clinical pattern of thyroid dysfunction and its relationship with survival marker in nonmetastatic NPC after immunotherapy.

METHODS

From January 1, 2019, to December 31, 2021, 165 pairs of nonmetastatic NPC patients (165 with and 165 without anti-PD-1 immunotherapy) matched by the propensity score matching method were included in this study. Thyroid function was assessed retrospectively before the first treatment and during each immunotherapy cycle.

RESULTS

The spectrum of thyroid dysfunction was different between the immunotherapy and control groups (P < 0.001). Compared with the control group, patients in the immunotherapy group developed more hypothyroidism (14.545% vs. 7.273%), less hyperthyroidism (10.909% vs. 23.636%), and a distinct pattern, biphasic thyroid dysfunction (3.030% vs. 0%). Immunotherapy also accelerates the onset of hypothyroidism, which was earlier with a median onset time difference of 32 days (P < 0.001). Patients who acquired thyroid dysfunction during immunotherapy had better complete biological response to treatment (OR, 10.980; P = 0.042).

CONCLUSIONS

For nonmetastatic NPC, thyroid dysfunction was associated with better response to treatment in immunotherapy but not in routine treatment. Thyroid function could be used as a predictor for survival and should be under regular and intensive surveillance in clinical practice of anti-PD-1 immunotherapy for nonmetastatic NPC.

Development and validation of a joint model for dynamic prediction of overall survival in nasopharyngeal carcinoma based on longitudinal post-treatment plasma cell-free Epstein-Barr virus DNA load

OBJECTIVES

To develop and validate a joint model for dynamic prediction of overall survival (OS) in nasopharyngeal carcinoma (NPC) based on longitudinal post-treatment plasma cell-free Epstein-Barr virus (cfEBV) DNA load.

PATIENTS AND METHODS

We analyzed 695 patients with non-metastatic NPC and detectable post-treatment cfEBV DNA load who did not receive adjuvant therapy. We fitted the trajectories of post-treatment cfEBV DNA load as a function of time into a linear mixed-effect model and fitted a Cox regression model with covariates including age, T and N stages, and lactate dehydrogenase level. Finally, we combined both via joint modeling to develop and validate our dynamic model.

RESULTS

A strong positive correlation was found between the individual longitudinal post-treatment cfEBV DNA load and the risk of death from any cause (P < 0.001). We developed a joint model capable of providing subject-specific dynamic prediction of conditional OS based on the evolution of the individual plasma cfEBV DNA load trajectory. The joint model showed reliable performance in both training and validation cohorts, with a large area under the curve (interquartile range [IQR]: training cohort, 0.775-0.850; validation cohort, 0.826-0.900) and low prediction errors (IQR: training cohort, 0.017-0.078; validation cohort, 0.034 -0.071). An increasing amount of data on cfEBV DNA load was associated with better model performance.

CONCLUSION

Our model provided reliable subject-specific dynamic prediction of conditional OS, which could help guide individualized post-treatment surveillance, risk stratification, and management of NPC in the future.

A Clinical-Radiomics Nomogram Based on Magnetic Resonance Imaging for Predicting Progression-Free Survival After Induction Chemotherapy in Nasopharyngeal Carcinoma

Purpose

This paper aimed to establish and verify a radiomics model based on magnetic resonance imaging (MRI) for predicting the progression-free survival of nasopharyngeal carcinoma (NPC) after induction chemotherapy (IC).

Materials and Methods

This cohort consists of 288 patients with clinical pathologically confirmed NPC, which was collected from January 2015 to December 2018. All NPC patients were randomly divided into two cohorts: training (n=202) and validation (n=86). Radiomics features from the MRI images of NPC patients were extracted and selected before IC. The patients were classified into high- and low-risk groups according to the median of Radscores. The significant imaging features and clinical variables in the univariate analysis were constructed for progression-free survival (PFS) using the multivariate Cox regression model. A survival analysis was performed using Kaplan–Meier with log-rank test and then each model’s stratification ability was evaluated.

Results

Epstein–Barr virus (EBV) DNA before treatment was an independent predictor for PFS (p &lt; 0.05). Based on the pyradiomic platform, we extracted 1,316 texture parameters in total. Finally, 16 texture features were used to build the model. The clinical radiomics-based model had good prediction capability for PFS, with a C-index of 0.827. The survival curve revealed that the PFS of the high-risk group was poorer than that of the low-risk group.

Conclusion

This research presents a nomogram that merges the radiomics signature and the clinical feature of the plasma EBV DNA load, which may improve the ability of preoperative prediction of progression-free survival and facilitate individualization of treatment in NPC patients before IC.

Circulating Plasma Epstein-Barr Virus DNA Load During the Follow-up Periods Predicts Recurrence and Metastasis in Nasopharyngeal Carcinoma

BACKGROUND

Epstein-Barr virus DNA (EBV DNA) load has been identified as a prognostic factor in nasopharyngeal carcinoma (NPC), whereas the dynamic changes in the long period have not been explored. In this study, we evaluated EBV DNA kinetics and its role in the survival.

METHODS

We conducted a retrospective review of 900 NPC patients. Plasma EBV DNA levels were measured at various time points after treatment. The correlations of EBV kinetics with recurrence and metastasis were analyzed. After stratifying patients according to the EBV results, survival was compared using Kaplan-Meier estimates. Twelve- and 24-month landmark analyses for overall survival (OS) data were performed according to the EBV groups.

RESULTS

Patients with post-EBV of less than 2500 copies/mL achieved better survival than did those with higher ones. Furthermore, patients with continuously elevated EBV DNA expressed significantly poorer OS (hazard ratio [HR], 2.542, 95% confidence interval [CI], 2.077-3.111; P < 0.001), distant metastasis-free survival (HR, 2.970; 95% CI, 2.392-3.687; P < 0.001), locoregional-free survival (HR, 1.699; 95% CI, 1.072-2.692; P = 0.013), and progression-free survival (HR, 2.535; 95% CI, 1.987-3.233; P < 0.001) than did patients with continuously normal EBV or those with elevated levels at any time point. The 5-year OS with elevated EBV was lower than that of the remission group by using the 12- and 24-month landmark analysis.

CONCLUSIONS

Elevated EBV DNA after treatment was a better predictive indicator of survival than the baseline concentrations. Furthermore, continuously elevated EBV DNA after treatment indicated recurrence, metastasis, and unfavorable prognosis for NPC. In addition, there were consistent patterns of EBV DNA kinetics during long-term follow-up, which warrant further study.

Tracking the Molecular Fingerprint of Head and Neck Cancer for Recurrence Detection in Liquid Biopsies

The 5-year relative survival for patients with head and neck cancer, the seventh most common form of cancer worldwide, was reported as 67% in developed countries in the second decade of the new millennium. Although surgery, radiotherapy, chemotherapy, or combined treatment often elicits an initial satisfactory response, relapses are frequently observed within two years. Current surveillance methods, including clinical exams and imaging evaluations, have not unambiguously demonstrated a survival benefit, most probably due to a lack of sensitivity in detecting very early recurrence. Recently, liquid biopsy monitoring of the molecular fingerprint of head and neck squamous cell carcinoma has been proposed and investigated as a strategy for longitudinal patient care. These innovative methods offer rapid, safe, and highly informative genetic analysis that can identify small tumors not yet visible by advanced imaging techniques, thus potentially shortening the time to treatment and improving survival outcomes. In this review, we provide insights into the available evidence that the molecular tumor fingerprint can be used in the surveillance of head and neck squamous cell carcinoma. Challenges to overcome, prior to clinical implementation, are also discussed.

Prognostic Value of Plasma Epstein-Barr Virus DNA Levels Pre- and Post-Neoadjuvant Chemotherapy in Patients With Nasopharyngeal Carcinoma

Background

In this study, we evaluated the prognostic value of the plasma levels of Epstein-Barr virus (EBV) DNA in patients with nasopharyngeal carcinoma (NPC) at different treatment stages.

Methods

We retrospectively analyzed the Data of 206 patients with NPC. Pre-neoadjuvant chemotherapy (pre-NACT), post-NACT, post-radiotherapy, and post-treatment plasma EBV DNA levels were used to establish prognostic nomograms. The concordance index (C-index) and calibration curves were used to compare the prognostic accuracy of the nomograms. The results were confirmed in a validation cohort consisting of patients who were tested for EBV DNA levels at all four stages of treatment. The Kaplan-Meier method was used to calculate the progression-free survival (PFS) and overall survival (OS). Survival differences were calculated using the log-rank test.

Results

EBV DNA-positive patients had worse 3-year PFS and 5-year OS than EBV DNA-negative patients; this was true for pre-NACT (PFS: 82.7% vs. 57.3%, P < 0.001; OS: 90.9% vs. 68.7%, P = 0.08) and post-NACT (PFS: 85.0% vs. 50.6%, P < 0.001; OS: 91.7% vs. 65.7%; P = 0.001) EBV DNA levels but not for post-radiotherapy (PFS: 72.2% vs. 60.9%, P = 0.192; OS: 73.1% vs. 77.2%, P = 0.472) or post-treatment (PFS: 77.3% vs. 59.2%, P = 0.063; OS: 77.5% vs. 79.7%, P = 0.644) levels. Nomograms combining pre-NACT and post-NACT EBV DNA levels had a superior prognostic ability than those of post-radiotherapy and post-treatment EBV DNA levels.

Conclusion

Pre-NACT EBV DNA levels combined with post-NACT EBV DNA levels can more reliably predict survival outcomes in patients with NPC.

The Chinese Society of Clinical Oncology (CSCO) clinical guidelines for the diagnosis and treatment of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor originating in the nasopharynx and has a high incidence in Southeast Asia and North Africa. To develop these comprehensive guidelines for the diagnosis and management of NPC, the Chinese Society of Clinical Oncology (CSCO) arranged a multi‐disciplinary team comprising of experts from all sub‐specialties of NPC to write, discuss, and revise the guidelines. Based on the findings of evidence‐based medicine in China and abroad, domestic experts have iteratively developed these guidelines to provide proper management of NPC. Overall, the guidelines describe the screening, clinical and pathological diagnosis, staging and risk assessment, therapies, and follow‐up of NPC, which aim to improve the management of NPC.

Design of InnoPrimers-Duplex Real-Time PCR for Detection and Treatment Response Prediction of EBV-Associated Nasopharyngeal Carcinoma Circulating Genetic Biomarker

Nasopharyngeal carcinoma (NPC) is an epithelial tumor with high prevalence in southern China and Southeast Asia. NPC is well associated with the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) 30 bp deletion by having its vital role in increased tumorigenicity and decreased immune recognition of EBV-related tumors. This study developed an InnoPrimers-duplex qPCR for detection of NPC blood circulating LMP1 30 bp deletion genetic biomarker for early diagnosis and treatment response prediction of NPC patients. The analytical and diagnostic evaluation and treatment response prediction were conducted using NPC patients’ whole blood (WB) and tissue samples and non-NPC cancer patients and healthy individuals’ WB samples. The assay was able to detect as low as 20 ag DNA per reaction (equivalent to 173 copies) with high specificity against broad reference microorganisms and archive NPC biopsy tissue and FNA samples. The diagnostic sensitivity and specificity were 83.3% and 100%, respectively. The 30 bp deletion genetic biomarker was found to be a good prognostic biomarker associated with overall clinical outcome of NPC WHO type III patients. This sensitive and specific assay can help clinicians in early diagnosis and treatment response prediction of NPC patients, which will enhance treatment outcome and lead to better life-saving.

Liquid biopsy posttreatment surveillance in endemic nasopharyngeal carcinoma: a cost-effective strategy to integrate circulating cell-free Epstein-Barr virus DNA

BACKGROUND

The optimal posttreatment surveillance strategy for nasopharyngeal carcinoma (NPC) remains unclear. Circulating cell-free Epstein-Barr virus (cfEBV) DNA has been recognized as a promising biomarker to facilitate early detection of NPC recurrence. Therefore, we aim to determine whether integrating circulating cfEBV DNA into NPC follow-up is cost-effective.

METHODS

For each stage of asymptomatic nonmetastatic NPC patients after complete remission to primary NPC treatment, we developed a Markov model to compare the cost-effectiveness of the following surveillance strategies: routine follow-up strategy, i.e., (1) routine clinical physical examination; routine imaging strategies, including (2) routine magnetic resonance imaging plus computed tomography plus bone scintigraphy (MRI + CT + BS); and (3) routine 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT); cfEBV DNA-guided imaging strategies, including (4) cfEBV DNA-guided MRI + CT + BS and (5) cfEBV DNA-guided PET/CT. Clinical probabilities, utilities, and costs were derived from published studies or databases. Sensitivity analyses were performed.

RESULTS

For all disease stages, cfEBV DNA-guided imaging strategies demonstrated similar survival benefits but were considerably more economical than routine imaging strategies. They only required approximately one quarter of the number of imaging studies compared with routine imaging strategies to detect one recurrence. Specifically, cfEBV DNA-guided MRI + CT + BS was most cost-effective for stage II (incremental cost-effectiveness ratio [ICER] $57,308/quality-adjusted life-year [QALY]) and stage III ($46,860/QALY) patients, while cfEBV DNA-guided PET/CT was most cost-effective for stage IV patients ($62,269/QALY). However, routine follow-up was adequate for stage I patients due to their low recurrence risk.

CONCLUSIONS

The cfEBV DNA-guided imaging strategies are effective and cost-effective follow-up methods in NPC. These liquid biopsy-based strategies offer evidence-based, stage-specific surveillance modalities for clinicians and reduce disease burden for patients.

Establishment and Validation of Nomogram Based on Combination of Pretreatment C-Reactive Protein/Albumin Ratio-EBV DNA Grade in Nasopharyngeal Carcinoma Patients Who Received Concurrent Chemoradiotherapy

Background

A higher ratio of pretreatment C-reactive protein/albumin ratio (CAR) is associated with poor prognosis in nasopharyngeal carcinoma (NPC), and Epstein–Barr virus (EBV) DNA level is known to not only participate in the occurrence of nasopharyngeal carcinoma but also affect the development and prognosis of the disease. Herein, we proposed that a combination of both these markers could improve the predictive prognostic ability.

Methods

In all, 842 NPC patients who received concurrent chemoradiotherapy (CCRT) were entered in this study. We collected all patients’ blood samples and EBV DNA copy numbers within one week before any treatment. Receiver operating characteristic (ROC) curve was used to determine the optimal cut-off. We employed the Kaplan–Meier method for survival analyses and the univariate and multivariate analyses (Cox proportional hazards regression model) for statistical analysis. A nomogram was constructed based on multivariate analyses results of the validation set. The model was internally validated using 1000 bootstrap samples to avoid overfitting. Another validation of 10-fold cross-validation was also applied. Calibration curves and concordance index (C-index) were calculated to determine predictive and discriminatory capacity.

Results

In the whole cohort, we observed that higher CAR, EBV DNA level, and CAR-EBV DNA (C-E) grade were associated with shorter overall survival (OS) and distant metastasis-free survival (DMFS) (all P<0.05). In univariate and multivariate analyses, C-E grade was an independent prognostic factor (all P<0.05). In the training set, we gained the similar results with the whole set. According to multivariate analyses of the training set, we constructed a nomogram. The results of bootstrap samples and 10-fold cross-validation showed favorable predictive efficacy. And calibration curves of the model provided credibility to its predictive capability.

Conclusion

C-E grade was confirmed as an independent prognostic predictor in patients with NPC who received CCRT. Higher level of pretreatment C-E grade could signify a higher risk of metastasis and shorter OS. The prognostic nomogram based on C-E grade was dependable in nasopharyngeal carcinoma patients.

A systematic review and recommendations on the use of plasma EBV DNA for nasopharyngeal carcinoma

INTRODUCTION

Nasopharyngeal carcinoma (NPC) is an endemic malignancy in Southeast Asia, particularly Southern China. The classical non-keratinising cell type is almost unanimously associated with latent Epstein-Barr virus (EBV) infection. Circulating plasma EBV DNA can be a useful biomarker in various clinical aspects, but comprehensive recommendations and international guidelines are still lacking. We conducted a systematic review of all original articles on the clinical application of plasma EBV DNA for NPC; we further evaluated its strengths and limitations for consideration as standard recommendations.

METHODS

The search terms 'nasopharyngeal OR nasopharynx', and 'plasma EBV DNA OR cell-free EBV OR cfEBV' were used to identify full-length articles published up to December 2020 in the English literature. Three authors independently reviewed the article titles, removed duplicates and reviewed the remaining articles for eligibility.

RESULTS

A total of 81 articles met the eligibility criteria. Based on the levels of evidence and grades of recommendation assessed, it is worth considering the inclusion of plasma EBV DNA in screening, pre-treatment work-up for enhancing prognostication and tailoring of treatment strategy, monitoring during radical treatment, post-treatment surveillance for early detection of relapse, and monitoring during salvage treatment for recurrent or metastatic NPC. One major limitation is the methodology of measurement requiring harmonisation for consistent comparability.

CONCLUSIONS

The current comprehensive review supports the inclusion of plasma EBV DNA in international guidelines in the clinical aspects listed, but methodological issues must be resolved before global application.

The evolution of the nasopharyngeal carcinoma staging system over a 10-year period: implications for future revisions

BACKGROUND

The classification criteria and staging groups for nasopharyngeal carcinoma described in the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) staging system have been revised over time. This study assessed the proportion of patients whose staging and treatment strategy have changed due to revisions of the UICC/AJCC staging system over the past 10 years (ie, from the sixth edition to the eighth edition), to provide information for further refinement.

METHODS

We retrospectively reviewed 1901 patients with non-metastatic nasopharyngeal carcinoma treated in our cancer center between November 2009 and June 2012. The Akaike information criterion and Harrell concordance index were applied to evaluate the performance of the staging system.

RESULTS

In total, 25 (1.3%) of the 1901 patients who were staged as T2a according to the sixth edition system were downgraded to T1 in the eighth edition; 430 (22.6%) staged as N0 in the sixth edition were upgraded to N1 in the eighth edition; 106 (5.6%) staged as N1/2 in the sixth edition were upgraded to N3 in the eighth edition. In addition, 51 (2.7%) and 25 (1.3%) of the study population were upstaged from stage I to stage II and stage II to stage IVa, respectively; 10 (0.5%) was downgraded from stage II to stage I. The survival curves of adjacent N categories and staging groups defined by eighth classification system were well-separated. However, there was no significant difference in the locoregional failure-free survival (P = 0.730) and disease-free survival (P = 0.690) rates between the T2 and T3 categories in the eighth edition classification system.

CONCLUSIONS

Modifications to the tumor-node-metastasis staging system over the past 10 years have resulted in N classification changes in numerous cases. Although the eighth edition tumor-node-metastasis staging system better predicts survival outcomes, the T classification could be simplified in future revisions.

Digital CRISPR-based method for the rapid detection and absolute quantification of nucleic acids

Rapid diagnostics of adventitious agents in biopharmaceutical/cell manufacturing release testing and the fight against viral infection have become critical. Quantitative real-time PCR and CRISPR-based methods rapidly detect DNA/RNA in 1 h but suffer from inter-site variability. Absolute quantification of DNA/RNA by methods such as digital PCR reduce this variability but are currently too slow for wider application. Here, we report a RApid DIgital Crispr Approach (RADICA) for absolute quantification of nucleic acids in 40-60 min. Using SARS-CoV-2 as a proof-of-concept target, RADICA allows for absolute quantification with a linear dynamic range of 0.6-2027 copies/μL (R² value > 0.99), high accuracy and low variability, no cross-reactivity to similar targets, and high tolerance to human background DNA. RADICA's versatility is validated against other targets such as Epstein-Barr virus (EBV) from human B cells and patients' serum. RADICA can accurately detect and absolutely quantify EBV DNA with similar dynamic range of 0.5-2100 copies/μL (R² value > 0.98) in 1 h without thermal cycling, providing a 4-fold faster alternative to digital PCR-based detection. RADICA therefore enables rapid and sensitive absolute quantification of nucleic acids which can be widely applied across clinical, research, and biomanufacturing areas.

Prognostic Significance of Radiologic Extranodal Extension in Nasopharyngeal Cancer

OBJECTIVE

The aim of the present study was to evaluate the prognostic value of radiologic extranodal extension (rENE) in patients with nasopharyngeal cancer.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary university hospital.

METHODS

We identified patients with nasopharyngeal cancer and lymph node metastasis who underwent pretreatment neck computed tomography or magnetic resonance imaging and evaluated rENE from the involved lymph node. Univariate Kaplan-Meier and multivariate Cox regression analyses were used to compare rENE+ and rENE- groups for local regional relapse-free survival, distant metastasis-free survival, and overall survival.

RESULTS

Of 61 cases, 24 (39.3%) were rENE+ and 37 (60.7%) were rENE-. The median follow-up was 65.5 months. The 5-year distant metastasis-free survival and overall survival rates were lower in the rENE+ group than the rENE- group (70.8% vs 89.2%, P = .016; 66.7% vs 89.2%, P = .01, respectively). Differences in locoregional control between the groups were not significant (P = .18). The 5-year rates for local regional relapse-free survival were 87.5% for rENE+ and 91.9% for rENE-. In multivariate analysis, the presence of rENE was a significant independent adverse prognostic factor for distant metastasis-free survival and overall survival.

CONCLUSIONS

We showed that rENE is an independent prognostic factor for poor distant control and survival in patients with nasopharyngeal cancer.

Prognostic Value of Programmed Cell Death-Ligand 1 Expression in Tumor-Infiltrating Lymphocytes and Viral Load in Peripheral Blood Mononuclear Cells for Epstein-Barr Virus-Positive Nasopharyngeal Carcinoma

BACKGROUND

Epstein-Barr virus (EBV) infection has a role in the development and progression of nasopharyngeal carcinoma (NPC); however, it is unclear whether EBV load correlates with tumor prognosis or the need for immunotherapy. This study evaluated whether the EBV DNA concentration in peripheral blood mononuclear cells (PBMC) or programmed cell death-ligand1 (PD-L1) expression in tumor-infiltrating lymphocytes (TIL) could predict the clinical outcomes of patients with NPC.

METHODS

Clinicopathological parameters of 198 patients with NPC were analyzed retrospectively from June 2012 to May 2018. Patients' EBV loads were determined by droplet digital PCR. TIL PD-L1 was analyzed by immunohistochemistry.

RESULTS

A log value of 1.98 log IU/mL for PBMC EBV DNA and a percentage of PD-L1 expression of 15% in TILs marked distinguishing cutoffs in NPC prognosis. The 5-year progression-free survival (PFS) rates in patients with high vs low log (PBMC EBV DNA) were 68.2% and 93.1%, respectively (P = 0.002). The 5-year PFS rates in patients with high vs low TIL PD-L1 expression were 66.3% and 33.7%, respectively (P = 0.03). The 5-year PFS rates of the high-risk group (high log [PBMC EBV DNA] and low TIL PD-L1), low-risk group (low log [PBMC EBV DNA] and high TIL PD-L1), and those in between (intermediate group) were 0%, 91.9%, and 71.4%, respectively (P < 0.001).

CONCLUSION

Concentrations of PBMC EBV DNA and TIL PD-L1 expression can be used as prognostic markers in NPC. The combination of both an increased EBV DNA concentration and suppressed TIL PD-L1 expression is associated with metastasis or relapse.

Validation of a Highly Sensitive qPCR Assay for the Detection of Plasma Cell-Free Epstein-Barr Virus DNA in Nasopharyngeal Carcinoma Diagnosis

Quantification of plasma cell-free Epstein Barr virus DNA (cf EBV DNA) has been suggested as a promising liquid biopsy assay for screening and early detection of nasopharyngeal carcinoma (NPC). However, the diagnostic value of this assay is currently not known in the population of Vietnam, one of the countries which contributed the most to the NPC cases. Herein, we have reported a highly sensitive quantitative polymerase chain reaction (qPCR)-based assay targeting cf EBV DNA for the detection of NPC. A standard curve with linear regression, R² = 0.9961 (range: 25-150 000 copies/mL) and a detection limit of 25 copies/mL were obtained using an EBV standard panel provided by the Chinese University of Hong Kong. The clinical performance of this assay was assessed using plasma samples obtained from 261 Vietnamese individuals. The optimized qPCR assay detected cf EBV DNA in plasma with a sensitivity of 97.4% and a specificity of 98.2%. The absolute quantitative results of pretreatment cf EBV DNA and patient overall clinical stages were statistically correlated (P < .05). In summary, the remarkably high sensitivity and specificity of our optimized qPCR assay strongly supports the wide use of cf EBV DNA quantification as a routine noninvasive method in early diagnosis and management of patients with NPC.

A Clinical-Radiomics Nomogram Based on Computed Tomography for Predicting Risk of Local Recurrence After Radiotherapy in Nasopharyngeal Carcinoma

Purpose: We aimed to establish a nomogram model based on computed tomography (CT) imaging radiomic signature and clinical factors to predict the risk of local recurrence in nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT). Methods: This was a retrospective study consisting of 156 NPC patients treated with IMRT. Radiomics features were extracted from the gross tumor volume for nasopharynx (GTVnx) in pretreatment CT images for patients with or without local recurrence. Discriminative radiomics features were selected after t-test and the least absolute shrinkage and selection operator (LASSO) analysis. The most stable model was obtained to generate radiomics signature (Rad_Score) by using machine learning models including Logistic Regression, K-Nearest neighbor, Naive Bayes, Decision Tree, Stochastic Gradient Descent, Gradient Booting Tree and Linear Support Vector Classification. A nomogram for local recurrence was established based on Rad_Score and clinical factors. The predictive performance of nomogram was evaluated by discrimination ability and calibration ability. Decision Curve Analysis (DCA) was used to evaluate the clinical benefits of the multi-factor nomogram in predicting local recurrence after IMRT. Results: Local recurrence occurred in 42 patients. A total of 1,452 radiomics features were initially extracted and seven stable features finally selected after LASSO analysis were used for machine learning algorithm modeling to generate Rad_Score. The nomogram showed that the greater Rad_Score was associated with the higher risk of local recurrence. The concordance index, specificity and sensitivity in the training cohort were 0.931 (95%CI:0.8765-0.9856), 91.2 and 82.8%, respectively; whereas, in the validation cohort, they were 0.799 (95%CI: 0.6458-0.9515), 79.4, and 69.2%, respectively. Conclusion: The nomogram based on radiomics signature and clinical factors can predict the risk of local recurrence after IMRT in patients with NPC and provide evidence for early clinical intervention.

Dynamic Changes of Post-Radiotherapy Plasma Epstein-Barr Virus DNA in a Randomized Trial of Adjuvant Chemotherapy Versus Observation in Nasopharyngeal Cancer

PURPOSE

To study the dynamic changes in plasma Epstein-Barr virus (pEBV) DNA after radiotherapy in nasopharyngeal cancer (NPC).

EXPERIMENTAL DESIGN

We conducted a randomized controlled trial of adjuvant chemotherapy versus observation in patients with NPC who had detectable pEBV DNA at 6 weeks post-radiotherapy. Randomized patients had a second pEBV DNA checked at 6 months post-randomization. The primary endpoint was progression-free survival (PFS).

RESULTS

We prospectively enrolled 789 patients. Baseline post-radiotherapy pEBV DNA was undetectable in 573 (72.6%) patients, and detectable in 216 (27.4%) patients, of whom 104 (13.2%) patients were eligible for randomization to adjuvant chemotherapy (n = 52) versus observation (n = 52). The first post-radiotherapy pEBV DNA had a sensitivity of 0.48, specificity of 0.81, area under receiver-operator characteristics curve (AUC) of 0.65, false positive (FP) rate of 13.8%, and false negative (FN) rate of 14.4% for disease progression. The second post-radiotherapy pEBV DNA had improved sensitivity of 0.81, specificity of 0.75, AUC of 0.78, FP rate of 14.3%, and FN rate of 8.1%. Patients with complete clearance of post-radiotherapy pEBV DNA (51%) had survival superior to that of patients without post-radiotherapy pEBV DNA clearance (5-year PFS, 85.5% vs. 23.3%; HR, 9.6; P < 0.0001), comparable with patients with initially undetectable post-radiotherapy pEBV DNA (5-year PFS, 77.1%), irrespective of adjuvant chemotherapy or observation.

CONCLUSIONS

Patients with NPC with detectable post-radiotherapy pEBV DNA who experienced subsequent pEBV DNA clearance had superior survival comparable with patients with initially undetectable post-radiotherapy pEBV DNA. Post-radiotherapy pEBV DNA clearance may serve as an early surrogate endpoint for long-term survival in NPC.

Integrating pre- and post-treatment Plasma Epstein-Barr Virus DNA levels for better prognostic prediction of Nasopharyngeal Carcinoma

Background: Pre- and post-treatment plasma Epstein‐Barr virus (EBV) DNA are important biomarkers for the prognosis of nasopharyngeal carcinoma (NPC). This study was performed to determine the prognostic potential of integrating EBV DNA levels in plasma measured pre-treatment (pre-EBV) and 3 months post-treatment (3 m-EBV).

Materials and methods: A total of 543 incident non-metastatic NPC patients treated with intensity-modulated radiotherapy, with or without chemotherapy, were reviewed. Patients were divided into four subgroups based on pre-EBV and 3 m-EBV status. The data for pre-EBV and 3 m-EBV samples were integrated, and the predictability of the survival of patients with NPC was analyzed.

Results: There were significant differences in the 5-year progression-free survival, distant metastasis-free survival, locoregional relapse-free survival, and overall survival among the four patient subgroups (P<0.001). Patients who tested negative for both pre-EBV and 3 m-EBV had the best prognosis, followed by patients who tested positive for pre-EBV and negative for 3 m-EBV, and those who tested negative for pre-EBV and positive for 3 m-EBV; however, patients who tested positive for both pre-EBV and 3 m-EBV had the poorest chances of survival. Multivariate analyses demonstrated that integration of pre-EBV and 3 m-EBV data was an independent predictor of NPC progression in patients. Receiver operating characteristic curve analysis further confirmed that the combination of pre-EBV and 3 m-EBV had a greater prognostic value than pre-EBV or 3 m-EBV alone.

Conclusions: Integrating pre-EBV and 3 m-EBV data could provide more accurate risk stratification and better prognostic prediction in NPC.

Clinical and survival analysis of nasopharyngeal carcinoma with consistently negative Epstein-Barr virus DNA

BACKGROUND

To assess the clinical and survival features of nasopharyngeal carcinoma (NPC) with consistently negative Epstein-Barr virus (EBV) DNA level.

METHODS

Propensity score matching (PSM) method was used to create well-balanced cohorts. Kaplan-Meier method and Cox proportional hazards models were performed to conduct survival analysis.

RESULTS

Four hundred and eighty patients were enrolled. Patients with consistently negative plasma EBV DNA level had a greater chance to present a relatively earlier T and N classification compared with those with positive EBV DNA level (p < .001; p = .015). And patients with consistently negative EBV level were significantly associated with preferable 3-year DFS (95.0% vs. 84.4%, p = .004), DMFS (98.3% vs. 89.4%, p = .009), and OS (100% vs. 97.6%, p = .004).

CONCLUSIONS

NPC patients with consistently negative EBV DNA level performed an earlier clinical stage and negative EBV DNA level was related to preferable survival outcomes.

Long-term monitoring of dynamic changes in plasma EBV DNA for improved prognosis prediction of nasopharyngeal carcinoma

Background

This study was performed to investigate whether long‐term monitoring of dynamic changes in plasma Epstein‐Barr virus (EBV) DNA could improve prognosis prediction of nasopharyngeal carcinoma (NPC).

Materials and methods

About 1077 nonmetastatic NPC patients were recruited to retrospectively analyze the prognostic value of plasma EBV DNA load pretreatment and 3, 12, 24, and 36 months posttreatment. We also examined the prognostic value of dynamic changes in plasma EBV DNA at various time points.

Results

Patients with plasma EBV DNA load above optimal pre‐ and posttreatment cut‐offs had significantly worse five‐year progression‐free survival, distant metastasis‐free survival, locoregional relapse‐free survival, and overall survival (OS) at all‐time points, excluding only OS at 36 months posttreatment due to limited mortalities. Patients with persistently undetectable plasma EBV DNA at the first four time points had the best prognosis, followed by those with positive detection pretreatment and consistently negative detection posttreatment, those with negative detection pretreatment and positive detection at one time point posttreatment, and those with positive detection pretreatment and at one time point posttreatment, whereas patients with positive detection at ≥2 time points posttreatment had the worst prognosis. Cox proportional hazard models identified the dynamic change pattern as an independent prognostic factor, and receiver operating characteristic curve analysis demonstrated that the dynamic change at four time point was more valuable than any single time point for predicting disease progression, distant metastasis, locoregional relapse, and mortality.

Conclusions

Dynamic changes in plasma EBV DNA pre‐ and posttreatment could predict the long‐term survival outcome and provide accurate risk stratification in NPC.

Clinical utility of Epstein-Barr virus DNA and other liquid biopsy markers in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor ubiquitously associated with the Epstein-Barr virus (EBV), which is highly prevalent in South China, Southeast Asia, and North Africa. Despite being a highly radio-sensitive and treatable cancer, a majority of NPC patients are diagnosed in their advanced stage, and locoregional and distant relapses following definitive treatment contribute largely to cancer-specific mortality among these patients. Given that EBV-driven NPC is the predominant variant seen in endemic regions, various EBV detection methods have been developed and are utilized in screening, prognostication, and post-treatment surveillance of NPC patients. While the Immunoglobulin A (IgA) serology assay is the most extensively studied EBV detection method, the detection of plasma EBV DNA released during replication or cellular apoptosis has shown superior outcomes in endemic population screening, prognostication, and detection of distant relapse. Furthermore, there is emerging evidence on the use of circulating tumor cells, microRNAs, DNA hypermethylation, and combination assays in various clinical scenarios. Herein, this paper provides a comprehensive overview of the relevant studies using various EBV detection techniques in the management of NPC. Specifically, the recent advances, clinical evidence, and challenges associated with the clinical application of EBV liquid biopsies in population screening, prognostication, and surveillance of NPC are presented.

Autocrine INSL5 promotes tumor progression and glycolysis via activation of STAT5 signaling

Metabolic reprogramming plays important roles in development and progression of nasopharyngeal carcinoma (NPC), but the underlying mechanism has not been completely defined. In this work, we found INSL5 was elevated in NPC tumor tissue and the plasma of NPC patients. Plasma INSL5 could serve as a novel diagnostic marker for NPC, especially for serum VCA-IgA-negative patients. Moreover, higher plasma INSL5 level was associated with poor disease outcome. Functionally, INSL5 overexpression increased, whereas knockdown of its receptor GPCR142 or inhibition of INSL5 reduced cell proliferation, colony formation, and cell invasion in vitro and tumorigenicity in vivo. Mechanistically, INSL5 enhanced phosphorylation and nuclear translocation of STAT5 and promoted glycolytic gene expression, leading to induced glycolysis in cancer cells. Pharmaceutical inhibition of glycolysis by 2-DG or blockade of INSL5 by a neutralizing antibody reversed INSL5-induced proliferation and invasion, indicating that INSL5 can be a potential therapeutic target in NPC. In conclusion, INSL5 enhances NPC progression by regulating cancer cell metabolic reprogramming and is a potential diagnostic and prognostic marker as well as a therapeutic target for NPC.

Integrating postradiotherapy plasma Epstein-Barr virus DNA and TNM stage for risk stratification of nasopharyngeal carcinoma to adjuvant therapy

BACKGROUND

After curative radiotherapy (RT) or chemoradiation (CRT), there is no validated tool to accurately identify patients for adjuvant therapy in nasopharyngeal carcinoma (NPC). Post-RT circulating plasma Epstein-Barr virus (EBV) DNA can detect minimal residual disease and is associated with recurrence and survival independent of TNM (tumor-lymph node-metastasis) stage. We aimed to develop and validate a risk model for stratification of NPC patients after completion of RT/CRT to observation or adjuvant therapy.

PATIENTS AND METHODS

The prospective multicenter 0502 EBV DNA screening cohort (Hong Kong NPC Study Group 0502 trial) enrolled from 2006 to 2015 (n = 745) was used for model development. For internal validation, we pooled independent patient cohorts from prospective clinical studies enrolled from 1997 to 2006 (n = 340). For external validation, we used retrospective cohort of NPC patients treated at Sun Yat-sen University Cancer Center from 2009 to 2012 (n = 837). Eligible patients had histologically confirmed NPC of Union for International Cancer Control (UICC) 7th Edition stage II-IVB who completed curative RT/CRT with or without neoadjuvant chemotherapy, had post-RT EBV DNA tested within 120 days after RT and received no adjuvant therapy. The primary end point was overall survival (OS). We used recursive-partitioning analysis (RPA) to classify patients into groups of low, intermediate, and high risk of death.

RESULTS

Combining post-RT EBV DNA level (0, 1-49, 50-499, and ≥500 copies/ml) and TNM stage (II, III, IVAB), RPA model classified patients into low-, intermediate-, and high-risk groups with 5-year OS of 89.4%, 78.5% and 37.2%, respectively. The RPA low-risk group had comparable OS to TNM stage II (5-year OS 88.5%) but identified more patients (64.8% versus stage II 28.1%) that could potentially be spared adjuvant therapy toxicity. The RPA model (c-index 0.712) showed better risk discrimination than either the TNM stage (0.604) or post-RT EBV DNA alone (0.675) with improved calibration and consistence. These results were validated in both internal and external cohorts.

CONCLUSION

Combining post-RT EBV DNA and TNM stage improved risk stratification in NPC.

Prognostic value of Epstein-Barr virus DNA level for nasopharyngeal carcinoma: a meta-analysis of 8128 cases

BACKGROUND

Plasma levels of Epstein-Barr virus (EBV) DNA have been employed to predict survival outcomes of patients with nasopharyngeal carcinoma (NPC). However, the prognostic value of subsequent EBV DNA levels (mid or post treatment) for NPC is needed to identify by a large cohort of patients. We performed a meta-analysis of studies including data from 8128 patients to evaluate the prognostic value of EBV DNA in NPC patients.

METHODS

We searched PubMed, Web of Science, and the Cochrane library for prospective and retrospective studies. Hazard ratios (HRs) and confidence intervals (CIs) were extracted from the studies or calculated and pooled to assess the association between EBV DNA levels pre-treatment (pre-DNA), mid-treatment (mid-DNA), and post-treatment (post-DNA) on clinical outcomes.

RESULTS

A total of 22 studies with 8128 patients was included for analysis. Pre-DNA levels predicted overall survival, progression-free survival, distant metastasis-free survival, and local-regional failure survival with HRs (95% CIs) of 2.70 (2.06, 3.54), 2.70 (2.12, 3.44), 3.49 (2.35, 5.17), and 2.00 (1.45, 2.76), respectively, and the corresponding HRs for post-DNA levels were 4.86 (3.30, 7.17), 6.29 (3.41, 11.60), 5.68 (2.71,11.93), respectively. Mid-DNA levels predicted overall survival and progression-free survival with an HR (95% CI) of 3.02 (1.54, 5.29) and 3.15 (2.05, 4.83). Subgroup analysis showed that the HR of post-DNA wasn't influenced by different detection time of post-DNA (P = 0.22, I² = 33.2%).

CONCLUSION

The EBV DNA levels have a significant prognostic impact in patients with NPC. The effect of post-treatment EBV DNA level dominated that of pre-DNA and mid-DNA levels.

Clinical value of a plasma Epstein-Barr virus DNA assay in the diagnosis of recurrent or metastatic nasopharyngeal carcinoma: a meta-analysis

BACKGROUND

To evaluate the diagnostic value of Epstein-Barr virus (EBV) DNA in nasopharyngeal carcinoma (NPC) patients with locoregional or distant recurrence.

METHODS

Articles related to the diagnosis of recurrent or metastatic NPC by the detection of EBV DNA in plasma or serum were retrieved from different databases. Sensitivity, specificity, summary receiver operating characteristic (SROC) curves, and likelihood ratios were pooled to assess the diagnostic value of individual diagnostic tests.

RESULTS

This meta-analysis pooled 25 eligible studies including 2496 patients with NPC. The sensitivity, specificity, positive likelihood ratio (+LR), and negative likelihood ratio (-LR) of EBV DNA in the diagnosis of NPC were 0.858 (95% confidence interval (CI): 0.801-0.901), 0.890 (95% CI: 0.866-0.909), 7.782 (95% CI: 6.423-9.429) and 0.159 (95% CI: 0.112-0.226), respectively. The diagnostic odds ratio (DOR) was 48.865 (95% CI: 31.903-74.845). The SROC for EBV DNA detection was 0.93 (95% CI: 0.90-0.95).

CONCLUSION

The detection of EBV DNA for the diagnosis of recurrent or metastatic NPC has good sensitivity and specificity and might be helpful in monitoring recurrent or metastatic NPC.

Liquid biopsy tracking during sequential chemo-radiotherapy identifies distinct prognostic phenotypes in nasopharyngeal carcinoma

Liquid biopsies have the utility for detecting minimal residual disease in several cancer types. Here, we investigate if liquid biopsy tracking on-treatment informs on tumour phenotypes by longitudinally quantifying circulating Epstein-barr virus (EBV) DNA copy number in 673 nasopharyngeal carcinoma patients undergoing radical induction chemotherapy (IC) and chemo-radiotherapy (CRT). We observe significant inter-patient heterogeneity in viral copy number clearance that is classifiable into eight distinct patterns based on clearance kinetics and bounce occurrence, including a substantial proportion of complete responders (≈30%) to only one IC cycle. Using a supervised statistical clustering of disease relapse risks, we further bin these eight subgroups into four prognostic phenotypes (early responders, intermediate responders, late responders, and treatment resistant) that are correlated with efficacy of chemotherapy intensity. Taken together, we show that real-time monitoring of liquid biopsy response adds prognostic information, and has the potential utility for risk-adapted treatment de-intensification/intensification in nasopharyngeal carcinoma.

Liquid biopsies are emerging as a useful method for diagnosis and prognosis in cancer. Here, the authors show the prognostic value of monitoring the level of circulating Epstein-barr virus DNA throughout induction chemotherapy and chemo-radiotherapy and its potential utility for risk-adapted individualised therapy in nasopharyngeal carcinomapatients.

Radiomics Model to Predict Early Progression of Nonmetastatic Nasopharyngeal Carcinoma after Intensity Modulation Radiation Therapy: A Multicenter Study

Purpose

To examine the prognostic value of a machine learning model trained with pretreatment MRI radiomic features in the assessment of patients with nonmetastatic nasopharyngeal carcinoma (NPC) who are at risk for 3-year disease progression after intensity-modulated radiation therapy and to explain the radiomics features in the model.

Materials and Methods

A total of 277 patients with nonmetastatic NPC admitted between March 2008 and December 2014 at two imaging centers were retrospectively reviewed. Patients were allocated to a discovery or validation cohort based on where they underwent MRI (discovery cohort, n = 217; validation cohort, n = 60). A total of 525 radiomics features extracted from contrast material-enhanced T1- or T2-weighted MRI studies and five clinical features were subjected to radiomic machine learning modeling to predict 3-year disease progression. Feature selection was performed by analyzing robustness to resampling, reproducibility between observers, and redundancy. Features for the final model were selected with Kaplan-Meier analysis and the log-rank test. A support vector machine was used as the classifier for the model. To interpret the pattern learned from the model, Shapley additive explanations (SHAP) was applied.

Results

The final model yielded an area under the receiver operating characteristic curve of 0.80 in both the discovery (95% bootstrap confidence interval: 0.80, 0.81) and independent validation (95% bootstrap confidence interval: 0.73, 0.89) cohorts. Analysis with SHAP revealed that tumor shape sphericity, first-order mean absolute deviation, T stage, and overall stage were important factors in 3-year disease progression.

Conclusion

These results add to the growing evidence of the role of radiomics in the assessment of NPC. By using explanatory techniques, such as SHAP, the complex interaction of features learned by the model may be understood.© RSNA, 2019Supplemental material is available for this article.

Clinical characteristics and prognostic value of pre-retreatment plasma epstein-barr virus DNA in locoregional recurrent nasopharyngeal carcinoma

PURPOSE

To define the clinical characteristics and prognostic value of pre-retreatment plasma Epstein-Barr virus (EBV) DNA, we investigated EBV status in locoregional recurrent nasopharyngeal carcinoma (lrNPC) patients.

METHODS

Between April 2008 and August 2016, the data of patients with nonmetastatic lrNPC were retrospectively reviewed. The survival indexes of patients between different pre-retreatment EBV status groups were compared.

RESULTS

A total of 401 patients with nonmetastatic lrNPC were enrolled, and 197 (49.1%) patients had detectable pre-retreatment plasma EBV DNA. Treatment included radiotherapy alone (n = 37 patients), surgery alone (n = 105), radiotherapy (n = 208), surgery combined with radiotherapy (n = 20), chemotherapy and targeted therapy (n = 31). Median follow-up was 32 months. The 3-year locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), and overall survival (OS) rates for the entire cohort were 64.8%, 89.4%, and 58.8%, respectively. The estimated 3-year LRRFS, DMFS, and OS rates for the pre EBV-positive group vs the pre EBV-negative group were 54.2% vs 75.0% (P < 0.001), 86.6% vs 91.9% (P = 0.05), 51.6% vs 65.9% (P = 0.01), respectively. Among patients in the clinical stage rI/II, there were 17 patients in the radiotherapy alone group and 49 patients in the surgery alone group. And there was no significant difference in overall survival between radiotherapy and surgery, even among the different pre-EBV statuses (P > 0.05). In terms of long-term toxic and side effects, the incidence of radioactive temporal lobe injury in the radiotherapy group was higher than that in the surgery group (35.3% vs 8.2%, P < 0.001), and no statistically significant difference was found in other long-term toxic and side effects.

CONCLUSIONS

The positive rate of pre-retreatment plasma EBV DNA in lrNPC is lower than primary NPC. The prognosis of EBV DNA negative group is better than positive group. For locally early-stage lrNPC, regardless of EBV DNA status, radiotherapy and surgery are available options and both can achieve better long-term survival.

The next decade of clinical trials in locoregionally advanced nasopharyngeal carcinoma

Clinical trials are powerful weapons in the battle against nasopharyngeal carcinoma (NPC). Based on clinical trials conducted in the past two decades, concurrent chemoradiotherapy combined with adjuvant chemotherapy or induction chemotherapy has been recommended as the standard treatment for locoregionally advanced NPC in various guidelines. However, there remain shortcomings concerning current treatment modalities that should be refined in future research. In this article, we review the achievements of published clinical trials for locoregionally advanced NPC and propose future directions for subsequent clinical trials. We believe that refinement of current regimens of chemotherapy, de-intensification of treatment for specific groups of patients, developing personalized treatment based on predictors ( e.g. applying plasma Epstein-Barr virus DNA) and investigating novel therapies, such as targeted therapy and immunotherapy, should be applied with the highest priority when designing clinical trials for locoregionally advanced NPC in the next decade.

Clinical features and survival outcomes between ascending and descending types of nasopharyngeal carcinoma in the intensity-modulated radiotherapy era: A big-data intelligence platform-based analysis

PURPOSE

To compare clinical features and survival outcomes in patients with ascending type (type A) and descending type (type D) nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era.

MATERIALS AND METHODS

A total of 5194 patients with type A and type D NPC treated at Sun Yat-sen University Cancer Center were randomly selected. Tumors that were mainly advanced local disease (T3-4 stage) with early stage cervical lymph node involvement (N0-1 stage) were determined as type A, while tumors with advanced lymph node disease (N2-3 stage) but early stage local invasion (T1-2 stage) were classified as type D NPC. Kaplan-Meier's analysis was used to evaluate survival rates, and log-rank test survival curves were used for comparison. In the multivariate analysis Cox proportional hazard models were developed.

RESULTS

There was a larger proportion of type A tumors (82%) than type D tumors (18%). Compared to patients with type A tumors, those with type D tumors had increased likelihood of distant metastasis, regional recurrence, disease recurrence, and death (P < 0.001 for all), however, not for local recurrence (P < 0.001). The HR (hazard ratio) for death following recurrence of disease for type D tumors were 1.6 compared to type A tumors. Multivariate analysis revealed that elevated EBV DNA, elevated lactate dehydrogenase, alcohol consumption, and no family history of cancer attributed to the development of type D tumors. Annual hazard rate in type A patients increased, peaking at 12-18 months after initial treatment and downward thereafter. Similar trend also occurred in type D during the first 5 years following treatment. Notably, a minor peak was also observed 7-8 years post treatment.

CONCLUSIONS

In the IMRT era, recurrence patterns differed across tumor types. Type D NPC had a more aggressive clinical course and worse outcomes compared with type A NPC.

Sodium butyrate induces autophagic apoptosis of nasopharyngeal carcinoma cells by inhibiting AKT/mTOR signaling

Previously, we confirmed the anti-tumor effects of sodium butyrate (NaBu) in nasopharyngeal carcinoma (NPC). However, its molecular mechanisms have not be fully elucidated. In this study, we studied the effects of NaBu on autophagy and explored the relation between NaBu associated autophagy and apoptosis in NPC cells. EGFP-LC3 plasmids were introduced into NPC cells to observed the effects of NaBu on autophagy flux with or without chloroquine (CQ) addition. Autophagy markers were also detected by Western blot. Under NaBu treatment, autophagy and apoptosis markers were detected simultaneously at different time. Then, to explore the roles of autophagy in NaBu induced apoptosis, the effects of autophagy inhibition, via specific inhibitor treatment or key gene knockdown, were analyzed. At last, the upstream signaling and its roles in NaBu induced autophagy and apoptosis were also analyzed. Increased LC3 dots and LC3-II accumulation indicated that NaBu can promote autophagy flux in NPC cells. LC3-II accumulation was earlier than cleaved PARP increment suggesting autophagy activation is prior to apoptosis activation, which was validated by flow cytometry mediated apoptosis analysis. Moreover, autophagy inhibition, achieved by 3-MA treatment or BECN1 knockdown, can antagonize NaBu induced apoptosis reflecting by re-deregulated cPARP and apoptotic rates. Furthermore, NaBu treatment inhibited the AKT/mTOR axis indicated by deregulated p-AKT(S473) and p-mTOR(S2448) and ectopic AKT expression both suppressed NaBu induced autophagy and apoptosis. At last, Western blot showed that HDAC6 dependent EGFR deregulation may account for the NaBu associated AKT/mTOR inhibition. NaBu can induce autophagic apoptosis via suppressing AKT/mTOR axis in NPC cells. Our results suggest that combination of autophagy inhibitors and deacetylase inhibitors may not be recommended in NPC clinical treatment.

The diagnostic and prognostic values of plasma Epstein-Barr virus DNA for residual cervical lymphadenopathy in nasopharyngeal carcinoma patients: a retrospective study

Background

Currently, the diagnosis and treatment of nasopharyngeal carcinoma (NPC) patients with residual cervical lymphadenopathy following radical radiotherapy with or without chemotherapy are challenging. We investigated the prognosis of NPC patients with residual cervical lymphadenopathy and assessed the diagnostic and prognostic values of Epstein-Barr virus (EBV) DNA in these patients.

Methods

This study included 82 NPC patients who were diagnosed with suspected residual cervical lymphadenopathy following completion of antitumor therapy. Their plasma EBV DNA levels were measured using quantitative polymerase chain reaction (qPCR) before the initiation of treatment and before neck dissection. Fine needle aspiration cytology (FNAC) was performed in 21 patients. All patients had undergone neck dissection and postoperative pathological examination to identify the nature of residual cervical lymphadenopathy. The overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS) were calculated using the Kaplan–Meier method and compared using the log-rank test. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Multivariable analysis was used to estimate the effect of potential prognostic factors on survival.

Results

Following a median follow-up of 52.6 months, compared with patients with negative postoperative pathological findings for residual cervical lymphadenopathy, the patients with positive findings had a significantly lower 3-year PFS rate (49.9% vs. 83.3%, P = 0.008). Among NPC patients with residual cervical lymphadenopathy, the patients with preoperative plasma EBV DNA > 0 copy/mL had a lower 3-year PFS rate than did those with no detectable EBV DNA (43.7% vs. 61.1%, P = 0.031). In addition, combining FNAC with preoperative EBV DNA detection improved the diagnostic sensitivity. Multivariable analysis demonstrated that residual cervical lymphadenopathy with positive postoperative pathological result was an independent prognostic factor for PFS and that detectable preoperative plasma EBV DNA was an independent prognostic factor for OS.

Conclusions

Using FNAC combined with preoperative EBV DNA detection improves the sensitivity in diagnosing NPC with residual cervical lymphadenopathy. Compared with patients with undetectable EBV DNA, patients with detectable preoperative plasma EBV DNA have worse prognosis and may require a more aggressive treatment strategy.

Depicting distant metastatic risk by refined subgroups derived from the 8th edition nasopharyngeal carcinoma TNM

BACKGROUND

Tumor-nodal-metastasis (TNM) is the most important survival predictor in nasopharyngeal carcinoma (NPC). Distant metastasis (DM) is the predominant failure pattern of NPC in the intensity-modulated radiotherapy (IMRT) era. The DM risk appears to be different for T-N subsets within the same clinical stage. Appropriately depicting DM risk has emerged as an important issue in tailoring individualized treatment and underpins the reason for this study.

METHODS

A total of 1616 non-metastatic (M0) NPC patients treated with IMRT were included. All were re-staged according to the 8th edition AJCC/UICC TNM (TNM-8). DM-free survival (DMFS) was calculated and compared among T-N subsets within each stage and DM risk groups were derived by Recursive-partitioning analysis (RPA) based on ordinal T and N categories.

RESULTS

Significant heterogeneity in DM risk was evident among T-N subsets within cTNM-8 stages II-IV. The RPA algorithm classified patients into four DM risk groups: RPA-I (T1N0-1 and T2-3N0), RPA-II (T2-3N1), RPA-III (T4N0-1 and T1-3N2) and RPA-IV (T4N2 and T1-4N3), with 5-year DMFS of 93.4% (95% CI: 91.3-96.1), 84.3% (80.8-87.8), 78.9% (75.4-82.4) and 63.6% (56.3-70.9), respectively (p < 0.001). Compared to cTNM-8 stage grouping, RPA grouping had a lower Akaike information criterion (AIC) and higher Harrell's concordance index (c-index) for DMFS.

CONCLUSIONS

Significant heterogeneity in DM risk exists among T-N subsets within cTNM-8 stages. The RPA groups demonstrated improved intra-group hazard consistency compared to cTNM-8 stage groups. While further validation is warranted, these RPA prognostic groupings provide a strong anatomic foundation to augment DM prediction for optimal targeting in future clinical trials.

Plasma Epstein-Barr virus DNA as an archetypal circulating tumour DNA marker

Analysis of circulating tumour DNA (ctDNA), as one type of ‘liquid biopsy’, has recently attracted great attention. Researchers are exploring many potential applications of liquid biopsy in many different types of cancer. In particular, it is of biological interest and clinical relevance to study the molecular characteristics of ctDNA. For such purposes, plasma Epstein–Barr virus (EBV) DNA from patients with nasopharyngeal carcinoma (NPC) would provide a good model to understand the biological properties and clinical applications of ctDNA in general. The strong association between EBV and NPC in endemic regions has made plasma EBV DNA a robust biomarker for this cancer. There are many clinical utilities of plasma EBV DNA analysis in NPC diagnostics. Its role in prognostication and surveillance of recurrence is well established. Plasma EBV DNA has also been validated for screening NPC in a recent large‐scale prospective study. Indeed, plasma EBV DNA could be regarded as an archetypal ctDNA marker. In this review, we discuss the biological properties of plasma EBV DNA from NPC samples and also the clinical applications of plasma EBV DNA analysis in the management of NPC. Of note, the recently reported size analysis of plasma EBV DNA in patients with NPC has highlighted size as an important analytical parameter of ctDNA and demonstrated clinical value in improving the diagnostic performance of an EBV DNA‐based NPC screening test. Such insights into ctDNA analysis (including size profiling) may help its full potential in cancer diagnostics for other types of cancer to be realised. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Relationship between pretreatment concentration of plasma Epstein-Barr virus DNA and tumor burden in nasopharyngeal carcinoma: An updated interpretation

Background

Pretreatment plasma Epstein‐Barr virus (EBV) DNA is an important tumor marker and prognostic factor in nasopharyngeal carcinoma (NPC). This study aimed to clarify the relationship between plasma EBV DNA level and tumor burden.

Materials and Methods

Pretreatment tumor burden was measured by radiologically delineated volumes, including nasopharynx tumor volume (GTVnx) and malignant nodes volume (GTVnd); pretreatment level of plasma EBV DNA was quantified by quantitative polymerase chain reaction. The relationship between natural logarithm of EBV DNA (ln‐DNA) and square root of tumor volume (sq‐GTV) was analyzed by Pearson correlation coefficient and partial correlation coefficient. Correlations in subgroups of tumor and nodal stages were also analyzed. A linear regression model was constructed to evaluate the contribution of tumor volumes to plasma EBV DNA. The prognostic effects of EBV DNA independent of tumor burden were evaluated.

Results

Two thousand two hundred and forty nine nonmetastatic NPC patients with detectable plasma EBV DNA were included in correlation analyses. Ln‐DNA showed significant correlation with sq‐GTVnx (r = 0.171) and sq‐GTVnd (r = 0.339) separately. Together, sq‐GTVnx and sq‐GTVnd could only explain 12.9% of the ln‐DNA. Tumor and nodal stages of disease could clearly influence the strength of relationship in subgroup analysis. After excluding confounding volume information, EBV DNA still can predict death and distant metastasis, but not locoregional relapse.

Conclusion

This study suggests that plasma EBV DNA is not only an index of tumor burden, but may also reflect other tumor features, such as accessibility to circulation, angiogenesis, tumor cell kinetics, metabolic activity, and metastatic potential, among others.

A novel scoring model to predict benefit of additional induction chemotherapy to concurrent chemoradiotherapy in stage II-IVa nasopharyngeal carcinoma

OBJECTIVES

Induction chemotherapy (IC) is gaining recognition for the treatment of nasopharyngeal carcinoma (NPC). We aimed to develop a model to predict benefit from additional IC to concurrent chemoradiotherapy (CCRT).

MATERIALS AND METHODS

From an NPC-specific database, 7413 patients with stage II-IVa disease who received CCRT with or without IC were included. Distant metastasis-free survival (DMFS) was the primary outcome and benefit from IC was evaluated by adjusted hazard ratio. Interaction terms between IC and other prognostic factors were identified in multivariate Cox model, and IC benefit score (ICBS) was calculated based on β coefficients from the Cox model.

RESULTS

Nodal category, overall stage, and pre-treatment plasma Epstein-Barr virus DNA (log transformed as continuous variable) interacted with IC and determined ICBS. ICBS could discriminate patients who benefited differently from IC in terms of DMFS well, especially for patients with high and low ICBS. As for patients with medium ICBS, predictive performance of ICBS seemed reduced.

CONCLUSIONS

Based on the ICBS model, we proposed a decision-making process to help in clinical practice. Multi-institutional and prospective studies are warranted to further validate our findings.

The EBV-Encoded Oncoprotein, LMP1, Induces an Epithelial-to-Mesenchymal Transition (EMT) via Its CTAR1 Domain through Integrin-Mediated ERK-MAPK Signalling

The Epstein–Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) oncogene can induce profound effects on epithelial growth and differentiation including many of the features of the epithelial-to-mesenchymal transition (EMT). To better characterise these effects, we used the well-defined Madin Darby Canine Kidney (MDCK) epithelial cell model and found that LMP1 expression in these cells induces EMT as defined by characteristic morphological changes accompanied by loss of E-cadherin, desmosomal cadherin and tight junction protein expression. The induction of the EMT phenotype required a functional CTAR1 domain of LMP1 and studies using pharmacological inhibitors revealed contributions from signalling pathways commonly induced by integrin–ligand interactions: extracellular signal-regulated kinases/mitogen-activated protein kinases (ERK-MAPK), PI3-Kinase and tyrosine kinases, but not transforming growth factor beta (TGFβ). More detailed analysis implicated the CTAR1-mediated induction of Slug and Twist in LMP1-induced EMT. A key role for β1 integrin signalling in LMP1-mediated ERK-MAPK and focal adhesion kianse (FAK) phosphorylation was observed, and β1 integrin activation was found to enhance LMP1-induced cell viability and survival. These findings support an important role for LMP1 in disease pathogenesis through transcriptional reprogramming that enhances tumour cell survival and leads to a more invasive, metastatic phenotype.