Prognostic efficacy of combining tumor volume with Epstein-Barr virus DNA in patients treated with intensity-modulated radiotherapy for nasopharyngeal carcinoma

Ninth Version of the AJCC and UICC Nasopharyngeal Cancer TNM Staging Classification

Importance

Accurate staging is a fundamental step in treating patients with nasopharyngeal carcinoma (NPC) worldwide; this is crucial not only for prognostication, but also for guiding treatment decisions. The American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) tumor-node-metastasis (TNM) system is the global language for clinicians, researchers, and cancer registries. Continual improvement that aligns with contemporary pattern of care is essential.

Objective

To improve the prognostic accuracy and clinical applicability of the eighth edition (TNM-8) for NPC.

Design, Setting, and Participants

This multicenter study analyzed patients with NPC with detailed tumor features during January 2014 and December 2015 and was reviewed by experienced radiologists. The data analysis was completed in December 2023. The findings were further confirmed with internal and external validation. Statistical analyses and clinical considerations were reviewed by the AJCC/UICC multidisciplinary head and neck panels and attained consensus. The recommendations were evaluated by the AJCC Evidence-Based Medicine Committee before final endorsement as the ninth version (TNM-9).

Main Outcomes and Measures

The primary end point was overall survival. Adjusted hazard ratios of different subgroups were then assessed for confirmation of optimal stage grouping.

Results

Of the 4914 patients analyzed, 1264 (25.7%) were female and 3650 (74.3%) were male; the median (SD) age was 48.1 (12.0) years. Advanced radiological extranodal extension (with involvement of adjacent muscles, skin, and/or neurovascular bundles) was identified as an independent adverse factor for all end points: this was added as a criterion for N3. Patients with nonmetastatic disease were regrouped into stages I to III instead of TNM-8 stages I to IVA. Significant hazard discrimination was achieved by grouping T1-2N0-1 as stage I, T3/N2 as stage II, and T4/N3 as stage III. Although the T1-2N0-1 subgroups had comparable 5-year overall survival, subdivisions into IA (T1-T2N0) and IB (T1-T2N1) were recommended due to the distinction in adjusted hazard ratios following adjustment for chemotherapy use. Metastatic disease was exclusively classified as stage IV, and prognostication was further refined by subdivision into IVA (M1a, ≤3 lesions) and IVB (M1b, >3 lesions). TNM-9 demonstrated superiority compared with TNM-8 in major statistical aspects.

Conclusion and Relevance

The results of this diagnostic study suggest that the ninth version of TNM staging for NPC, based on robust analyses and a comprehensive review by the AJCC/UICC staging committees, provides an improved staging system for global application and a framework for future incorporation of nonanatomical factors. This will be launched for global application in January 2025.

The value of integrating tumor volume and plasma Epstein-Barr virus DNA load during sequential chemoradiotherapy for prognostic prediction and therapeutic guidance in high-risk locoregionally advanced nasopharyngeal carcinoma

OBJECTIVES

To investigate the value of integrating primary gross tumor volume (GTVp) and gross tumor volume of nodes (GTVn) after induction chemotherapy (IC) and dynamic changes in plasma cell-free Epstein-Barr virus DNA (cfEBV DNA) during sequential chemoradiotherapy (CRT) in high-risk locoregionally advanced nasopharyngeal carcinoma (LA-NPC).

MATERIALS AND METHODS

We retrospectively reviewed 988 patients with LA-NPC undergoing IC plus concurrent chemoradiotherapy (CCRT) between 2014 and 2018. The entire cohort was divided into four subgroups according to tumor volume and the cfEBV DNA load. Using a supervised statistical clustering approach, we stratified the subgroups into three clusters. Overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS) and locoregional relapse-free survival (LRRFS) were calculated using Kaplan-Meier analysis and inter-group differences were compared using the log-rank test.

RESULTS

We observed that GTVp & GTVn and cfEBV DNApostIC & cfEBV DNApostCRT were powerful prognostic factors for OS (p = 0.004, p < 0.001, p < 0.001, and p < 0.001, respectively). The survival curves of the three clusters were significantly different. The 5-year OS for the low-risk, intermediate-risk and high-risk clusters were 97.0%, 86.2% and 77.1% (all P values < 0.001), respectively. The risk stratification system showed better predictive performance than the current tumor-node-metastasis (TNM) classification for OS (area under curve [AUC]: 0.653 versus 0.560, p < 0.001), DFS (AUC: 0.639 versus 0.540, p < 0.001), DMFS (AUC: 0.628 versus 0.535, p < 0.001) and LRRFS (AUC: 0.616 versus 0.513, p < 0.001).

CONCLUSION

Both tumor volume and the cfEBV DNA level during sequential CRT are effective prognostic indicators for patients with high-risk LA-NPC. The developed risk stratification system incorporating above factors improved survival prediction and demonstrated potential value in decision-making.

Nomograms incorporating primary tumor response at mid-radiotherapy to predict survival in locoregionally advanced nasopharyngeal carcinoma

BACKGROUND

A nomogram that incorporates tumor response at mid-radiotherapy (mid-RT) to predict the prognosis of locoregionally advanced nasopharyngeal carcinoma (LA-NPC) has not been established.

METHODS

This study retrospectively reviewed 583 patients with LA-NPC who underwent magnetic resonance imaging scans at mid-RT (the fourth week of RT) between 2015 and 2019.

RESULTS

Primary tumor (PT) response at mid-RT was found to predict disease-free survival (DFS) and overall survival (OS). Independent factors from multivariable analysis to predict DFS and OS were assembled into nomograms with (nomograms Amid-RT and Bmid-RT ) or without (nomograms Abaseline and Bbaseline ) PT response. Internal validation revealed good performance of these nomograms in discrimination: C-statistics = 0.761 for nomogram Amid-RT and 0.809 for nomogram Bmid-RT , which showed better discrimination performance than (C-statistics: 0.755) nomogram Abaseline and (C-statistics: 0.798) nomogram Bbaseline (Z-statistic = 2.476, p < 0.05; Z-statistic = 1.971, p < 0.05).

CONCLUSION

The nomograms based on PT response at mid-RT showed favorable predictive accuracy for DFS and OS in patients with LA-NPC.

The Dynamic Change in Plasma Epstein-Barr Virus DNA Load over a Long-Term Follow-Up Period Predicts Prognosis in Nasopharyngeal Carcinoma

The current study was designed to investigate the changes in the circulating Epstein−Barr virus DNA load (EBV DNA) at various time points before and after treatment and its clinical significance in nasopharyngeal carcinoma (NPC). A total of 142 patients with NPC were prospectively enrolled in this study. The plasma EBV DNA concentration was measured before and after treatment using qPCR. The prognostic values of the EBV DNA load were analyzed using the Kaplan−Meier and Cox regression tests. Following multivariate analysis, our data showed that high pre-EBV DNA loads were associated with significantly poorer distant metastasis free survival (DMFS) and progression free survival (PFS); detectable end-EBV DNA loads were associated with significantly worse loco-regional recurrence free survival (LRRFS) and PFS, and the detecTable 6 months-post-EBV DNA loads were associated with significantly poorer overall survival (OS), DMFS and PFS (p < 0.05). Additionally, combining the pre-EBV DNA load and the stage of the disease, our results showed that patients at stage III-IVA with a low pre-EBV DNA load had similar survival rates as patients at stage II with a low or high pre-EBV DNA load, but had better survival rates than those at stage III-IVA with a high pre-EBV DNA load. Taken together, we showed that the change of the EBV DNA load measured at several time points was more valuable than at any single time point for predicting patients’ survival for NPC. Furthermore, combining the pre-EBV DNA load and the TNM classification could help to formulate an improved prognostic model for this cancer.

Comparing BamHI-W and CE-marked assays to detect circulating Epstein-Barr Virus (EBV) DNA of nasopharyngeal cancer patients in a non-endemic area

OBJECTIVES

Plasma Epstein-Barr Virus (EBV)-DNA is a well-established prognostic biomarker in nasopharyngeal carcinoma (NPC). Different methods for assessment include single-copy gene targeted, European Conformity (CE)-marked assays, which are mostly employed in non-endemic settings, vs multiple-copy gene targeted, in-house BamHI-W based assays, which currently represent the most widely used method for EBV-DNA quantification. To date, evidence concerning the commutability of these different assays is still limited.

MATERIALS AND METHODS

From August 2016 to March 2018, 124 plasma and 124 whole blood (WB) samples from 93 NPC patients were collected at different time-points for each patient. EBV-DNA viral load was quantified in pre- (n = 12) and post-treatment (n = 9), follow-up (n = 53), and recurrent/metastatic (R/M) (n = 50) phase. For each sample, one in-house BamHI-W vs three different CE-marked plasma assays were compared; the performance of plasma vs WB matrix was also assessed. Quantitative agreement of EBV-DNA values was evaluated by linear correlation and Bland-Altman analysis.

RESULTS

A statistically significant (p = 0.0001) agreement between all CE-marked and the BamHI-W assays was found using plasma matrix, regardless of clinical phase. The results obtained in copies/ml were comparable to those expressed in IU/ml. When using WB matrix, the number of positive detections increased in the post-treatment phase.

CONCLUSIONS

Our retrospective comparison supported an agreement between Plasma BamHI-W and CE-marked assays in measuring EBV-DNA for non-endemic NPC patients. There were no significant interferences from different measurement units (IU/ml vs copies/ml). Further evaluations are needed to better clarify the role of WB.

Prognostic value of systemic inflammation response index in nasopharyngeal carcinoma with negative Epstein-Barr virus DNA

Background

Inflammatory parameters and Epstein–Barr virus (EBV) DNA status have been confirmed to be associated with prognosis in nasopharyngeal carcinoma (NPC) patients. However, there are few in-depth studies on the prognosis of NPC patients with negative EBV DNA. Our study aimed to look for inflammatory biomarkers that can identify disease progression in NPC patients with negative EBV DNA.

Methods

A total of 795 NPC patients were recruited, and ultimately 325 NPC patients with negative EBV DNA were included in this study (170 in training cohort and 155 in validation cohort). Kaplan–Meier method and log-rank test were used to analyze progression-free survival (PFS) and overall survival (OS). The multivariate analysis of Cox proportional hazards regression model was used to determine the independent prognostic factors. Receiver operating characteristic (ROC) curves were used to assess prognostic value. The logistic regression was used to evaluate the relationship between EBV DNA status and inflammatory parameters. The correlation between clinical characteristics was analyzed by the chi-squared test or the Fisher’s exact test.

Results

The optimal cutoff point for the SIRI was 1.12. The EBV DNA-negative NPC patients with high SIRI level had worse PFS and OS (all p < 0.001). In multivariate Cox proportional hazard models analysis, SIRI was an independent prognostic factor for PFS and OS (all p < 0.05), and had higher prognostic value than other indicators. Above results were found in the training cohort and confirmed in the validation cohort. In addition, EBV DNA status was not associated with any inflammatory parameters.

Conclusions

The SIRI can provide more accurate risk stratification and better prognostic prediction for NPC patients with negative EBV DNA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09942-1.

Nomogram for distant metastasis-free survival in patients with locoregionally advanced nasopharyngeal carcinoma

OBJECTIVE

To develop and validate a nomogram to predict distant metastasis-free survival of patients with locoregionally advanced nasopharyngeal carcinoma.

METHODS

We collected the total clinical data of 820 nasopharyngeal carcinoma (NPC) patients, of whom 482 formed the training cohort from one hospital and 328 made up the validation cohort from another hospital. By analyzing the prognosis of all patients after intensity-modulated radiotherapy by univariate and multivariate Cox regression models, a nomogram related to DMFS was created in the training cohort. The discriminatory and calibration power of the nomogram was successively assessed in the training and validation cohorts by the C‑index and calibration curve. The predictive ability for 3‑year DMFS was compared between the nomogram and TNM stage using ROC curves. Patients were divided into different risk groups based on scores calculated from the nomogram.

RESULTS

Age, lymph node gross tumor volume (GTVnd), and gross tumor volume of the nasopharynx (GTVnx) were the factors included in the nomogram. The C‑index of the nomogram was 0.721 in the training cohort and 0.750 in the validation cohort. The calibration curves were satisfactory. Patients in the high-risk group were more likely to develop metastases.

CONCLUSION

A nomogram incorporating age, GTVnd, and GTVnx showed good performance for predicting DMFS in patients with locoregionally advanced NPC.

Development and prospective validation of a risk score model in guiding individualized concurrent chemoradiotherapy in stage II nasopharyngeal carcinoma in intensity-modulated radiotherapy era

Purpose

We aimed to develop and prospectively validate a risk score model to guide individualized concurrent chemoradiotherapy (CCRT) for patients with stage II nasopharyngeal carcinoma (NPC) in intensity‐modulated radiotherapy (IMRT) era.

Materials and Methods

In total, 1220 patients who received CCRT or IMRT alone were enrolled in this study, including a training cohort (n = 719), a validation cohort (n = 307), and a prospective test cohort (n = 194). Patients were stratified into different risk groups by a risk score model based on independent prognostic factors, which were developed in the training cohort. Survival rates were compared by the log‐rank test. The validation and prospective test cohorts were used for validation.

Results

Total tumor volume, Epstein–Barr virus DNA, and lactate dehydrogenase were independent risk factors for failure‐free survival (FFS, all p < 0.05). A risk score model based on these three risk factors was developed to classify patients into low‐risk group (no risk factor, n = 337) and high‐risk group (one or more factors, n = 382) in the training cohort. In the high‐risk group, CCRT had better survival rates than IMRT alone (5‐year FFS: 82.6% vs. 74.0%, p = 0.028). However, there was no survival difference between CCRT and IMRT alone either in the whole training cohort (p = 0.15) or in the low‐risk group (p = 0.15). The results were verified in the validation and prospective test cohorts.

Conclusion

A risk score model was developed and prospectively validated to precisely select high‐risk stage II NPC patients who can benefit from CCRT, and thus guided individualized treatment in IMRT era.

Prognostic Factors for Overall Survival in Nasopharyngeal Cancer and Implication for TNM Staging by UICC: A Systematic Review of the Literature

This study aims to identify prognostic factors in nasopharyngeal carcinoma (NPC) to improve the current 8th edition TNM classification. A systematic review of the literature reported between 2013 and 2019 in PubMed, Embase, and Scopus was conducted. Studies were included if (1) original clinical studies, (2) ≥50 NPC patients, and (3) analyses on the association between prognostic factors and overall survival. The data elements of eligible studies were abstracted and analyzed. A level of evidence was synthesized for each suggested change to the TNM staging and prognostic factors. Of 5,595 studies screened, 108 studies (44 studies on anatomical criteria and 64 on non-anatomical factors) were selected. Proposed changes/factors with strong evidence included the upstaging paranasal sinus to T4, defining parotid lymph node as N3, upstaging N-category based on presence of lymph node necrosis, as well as the incorporation of non-TNM factors including EBV-DNA level, primary gross tumor volume (GTV), nodal GTV, neutrophil-lymphocyte ratio, lactate dehydrogenase, C-reactive protein/albumin ratio, platelet count, SUVmax of the primary tumor, and total lesion glycolysis. This systematic review provides a useful summary of suggestions and prognostic factors that potentially improve the current staging system. Further validation studies are warranted to confirm their significance.

Serum EA-IgA and D-dimer, but not VCA-IgA, are associated with prognosis in patients with nasopharyngeal carcinoma: a meta-analysis

Background

Patients with nasopharyngeal cancer (NPC) differ in prognosis, even at the same stage; therefore, new biomarkers are urgently required to identify early-stage NPC patients at high risk of poor prognosis. Although Epstein–Barr virus (EBV) DNA has been used for prognosis, the value of many other biomarkers expressed during the infection cycle of EBV remains unclarified. This study aimed to evaluate the prognostic potential of EA-IgA, VCA-IgA and d-dimer in patients with NPC.

Methods

Electronic databases, including PubMed, Embase and Web of Science, were searched up to February 1, 2021. Pooled data were extracted from studies that evaluated the relationship between NPC and overall survival (OS), distant metastasis-free survival (DMFS) or disease-free survival (DFS) and then were subjected to a meta-analysis.

Results

Nine studies with 5729 patients were included in this meta-analysis. In patients with NPC, EA-IgA levels significantly predicted OS (HR = 1.63, 95% CI 1.07–2.48). d-Dimer levels significantly predicted OS (HR = 1.75, 95% CI 1.24–2.47) and DMFS (HR = 1.91, 95% CI 1.31–2.79). However, high levels of VCA-IgA were not associated with OS (HR = 1.24, 95% CI 0.95–1.60), DMFS (HR = 1.41, 95% CI 0.92–2.17) or DFS (HR = 2.39, 95% CI 0.78–7.26).

Conclusions

The present findings reveal that EA-IgA and d-dimer, but not VCA-IgA, can be used as prognostic biomarkers in NPC.

Predictive Value of ERCC1 mRNA Level from Receiver-Operator Characteristic and Pretreatment EBV-DNA Virus Load in Stage II Nasopharyngeal Carcinoma Patients Receiving Intensity-Modulated Radiotherapy with Concurrent Cisplatin

Background: The molecular mechanisms underlying chemoresistance are still poorly understood in nasopharyngeal cancer; the protein expression of ERCC1 in DNA repair genes has been reported related to resistance platinum and predicting treatment outcomes in various malignant carcinomas, but the benefit for predicting outcomes with optimal cutoff value of ERCC1mRNA is controversial. The level of plasma Epstein-Barr virus (EBV) DNA is positively correlated with clinical stages of nasopharyngeal carcinoma (NPC). The predictive value of ERCC1mRNA from receiver-operator characteristic (ROC) and EBV-DNA level for stratified treatment with stage II NPC is exactly unclear. This study aims to assess the predictive value of combined EBV-DNA and ERCC1 in stage II nasopharyngeal cancer (NPC) patients treated with intensity-modulated radiotherapy (IMRT) with concurrent cisplatin, and provide guidance for future stratified treatment. Methods: A total of 86 stage II NPC patients who received IMRT and concurrent cisplatin-based chemotherapy with or without cisplatin-based adjuvant chemotherapy had measurements of ERCC1 mRNA, and pretreatment EBV-DNA levels were analyzed by real-time PCR (RT-PCR). Associations of ERCC1 mRNA and pretreatment EBV-DNA levels with clinical characteristics and survivals were evaluated. Results: Cutoff value of ERCC1 mRNA obtained from ROC curve was used, and there were significant differences in progression-free survival (PFS) and overall survival (OS) and overall response rate (ORR) between high expression group and low expression group (p = 0.021 and 0.030 and 0.000, respectively). Patients with pretreatment EBV-DNA <2000 copies/mL had significantly better PFS and ORR (p = 0.024 and 0.043, respectively) and a marginally significant impact on OS (p = 0.062) than those with pretreatment EBV-DNA ≥2000 copies/mL. Patients were divided into three groups by combination of ERCC1 mRNA and EBV-DNA level: ERCC1 mRNA low expression/pre-EBV-DNA <2000 copies/mL, ERCC1 mRNA low expression/pre-EBV-DNA ≥2000 copies/mL, and ERCC1 mRNA high expression/pre-EBV-DNA ≥2000 copies/mL. There were significant differences in ORR among the three groups (p = 0.005). The median follow-up was 62 months (range 22-84) with a follow-up rate of 90.70%. In these groups by combination of ERCC1 mRNA and EBV-DNA level, 1, 3, 5-year OS were 100%, 100%, 100%; 100%, 94.1%, 90.9%; and 100%, 85%, 72.9%, respectively (p = 0.038); 1, 3, 5-year PFS were 100%, 100%, 100%; 97.1%, 91.2%, 84.8%; and 95%, 85%, 71.4%, respectively (p = 0.028). Multivariate analysis showed that combination of ERCC1 mRNA and EBV-DNA levels remained independent prognostic factor but not ERCC1 mRNA and EBV-DNA alone. Conclusions: Combined ERCC1 mRNA and pre-EBV-DNA is a better prognostic biomarker in stage II NPC patients treated with concurrent chemoradiation. Patients with ERCC1 mRNA high expression/pre-EBV-DNA ≥2000 copies/mL may benefit from more aggressive treatment.

Prognostic efficacy of the combination of the pretreatment systemic Immune-Inflammation Index and Epstein-Barr virus DNA status in locally advanced Nasopharyngeal Carcinoma Patients

Background: The systemic immune-inflammation index (SII) and Epstein-Barr virus DNA (EBV DNA) levels has been used as a prognostic marker for nasopharyngeal carcinoma (NPC) patients, but there is no in-depth study in locally advanced NPC patients and no research on the predictive value of their combination. Our study aimed to evaluate the prognostic efficacy of the pretreatment SII, EBV DNA levels and their combination in locally advanced NPC patients receiving induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT).

Materials and methods: 319 patients diagnosed with locally advanced NPC receiving IC followed by CCRT were retrospectively reviewed (213 in the training cohort and 106 in the validation cohort). The cut-off value for the SII was determined using receiver operating characteristic (ROC) curve. Correlations between characteristics of patients were assessed using the Pearson correlation coefficient. Survival curves for the SII, EBV DNA levels and their combination were analyzed using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate analyses were performed by the Cox proportional hazards regression model to evaluate the prognostic impact on overall survival (OS) and progression-free survival (PFS). A prognostic nomogram was generated and its prediction ability was measured by the concordance index (C-index).

Results: The optimal cutoff point for the SII was 402.10. A higher SII and EBV DNA positivity were demonstrated to be related to poorer survival outcomes (P < 0.05). Multivariate analyses showed that a higher SII, EBV DNA positivity and their combination were powerful independent risk factors for OS and PFS (P < 0.05). The SII - EBV DNA had the largest area under the curve (AUC) compared to either score alone. The incorporation of the SII - EBV DNA into established nomogram achieved higher C-index in the prediction of OS and PFS, indicating its superior for predicting survival. All results were found in the training cohort and confirmed in the validation cohort.

Conclusions: The pretreatment SII and EBV DNA levels are promising factors for predicting survival in locally advanced NPC patients. The combination of them, which was superior to either score alone, was a complement to the conventional TNM staging system.

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.

Usefulness of Hybrid PET/MRI in Clinical Evaluation of Head and Neck Cancer Patients

(1) Background: The novel hybrid of positron emission tomography/magnetic resonance (PET/MR) examination has been introduced to clinical practice. The aim of our study was to evaluate PET/MR usefulness in preoperative staging of head and neck cancer (HNC) patients (pts); (2) Methods: Thirty eight pts underwent both computed tomography (CT) and PET/MR examination, of whom 21 pts underwent surgical treatment as first-line therapy and were further included in the present study. Postsurgical tissue material was subjected to routine histopathological (HP) examination with additional evaluation of p16, human papillomavirus (HPV), Epstein-Barr virus (EBV) and Ki67 status. Agreement of clinical and pathological T staging, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of CT and PET/MR in metastatic lymph nodes detection were defined. The verification of dependences between standardized uptake value (SUV value), tumor geometrical parameters, number of metastatic lymph nodes in PET/MR and CT, biochemical parameters, Ki67 index, p16, HPV and EBV status was made with statistical analysis of obtained results; (3) Results: PET/MR is characterized by better agreement in T staging, higher specificity, sensitivity, PPV and NPV of lymph nodes evaluation than CT imaging. Significant correlations were observed between SUVmax and maximal tumor diameter from PET/MR, between SUVmean and CT tumor volume, PET/MR tumor volume, maximal tumor diameter assessed in PET/MR. Other correlations were weak and insignificant; (4) Conclusions: Hybrid PET/MR imaging is useful in preoperative staging of HNC. Further studies are needed.

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.

An integrated model of the gross tumor volume of cervical lymph nodes and pretreatment plasma Epstein-Barr virus DNA predicts survival of nasopharyngeal carcinoma in the intensity-modulated radiotherapy era: a big-data intelligence platform-based analysis

Background:

Few studies have evaluated the prognostic value of the integrated model consisting of gross tumor volume of lymph nodes (GTVnd) and pretreatment plasma Epstein–Barr virus DNA (pre-EBV DNA) in nasopharyngeal carcinoma (NPC) patients.

Methods:

A well-established big-data intelligence platform with 10,126 NPC patients was used for a retrospective review. A total of 1500 cases with cervical nodal metastases but without distant metastases were randomly assigned to a training (n = 503) or test condition (n = 997) for analyses. The cut-off point for the GTVnd derived from the receiver operating characteristic (ROC) curve was combined with the published cut-off point for pre-EBV DNA to develop an integrated model by which patients were classified into four groups.

Results:

Both GTVnd and pre-EBV DNA were independent prognostic factors. Regardless of whether patients received induction chemotherapy (IC), the 5-year distant metastasis-free survival (DMFS) (69.5%) and overall survival (OS) (68.4%) were significantly worse in those with both a GTVnd >20 ml and pre-EBV DNA >2000 copies/ml (all p-values < 0.001). In patients with IC, all others had better 5-year DMFS and OS; in patients without IC, those with either a GTVnd >20 ml or pre-EBV DNA >2000 copies/ml had the medium 5-year DMFS and OS, while patients with neither of them had the best.

Conclusions:

The integrated GTVnd and pre-EBV DNA model not only predicted DMFS and OS in NPC patients effectively, but was an indicator of timely adjustment of therapeutic strategies for NPC patients, especially those completing IC.

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.

Long Noncoding RNAs and Messenger RNAs Expression Profiles Potentially Regulated by ZBTB7A in Nasopharyngeal Carcinoma

Our previous studies showed that ZBTB7A played an important role in promoting nasopharyngeal carcinoma (NPC) progression. However, molecular mechanisms of different levels of ZBTB7A are still unclear. It is necessary to search molecular markers which are closely connected with ZBTB7A. We selected NPC sublines CNE2 with stably transfecting empty plasmid (negative control, NC) and short hair RNA (shRNA) plasmid targeting ZBTB7A as research objectives. Microarray was used to screen differentially expressed long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) via shRNA-CNE2 versus NC-CNE2. Quantitative PCR (qPCR) was used to validate lncRNAs and mRNAs from the sublines, chronic rhinitis, and NPC tissues. Bioinformatics was used to analyze regulatory pathways which were connected with ZBTB7A. The 1501 lncRNAs (long noncoding RNAs) and 1275 differentially expressed mRNAs were upregulated or downregulated over 2-fold. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the upregulated or downregulated carbohydrate and lipid metabolisms probably involved in carcinogenicity of shRNA-CNE2 (P-value cut-off was 0.05). In order to find the molecular mechanisms of ZBTB7A, we validated 12 differentially expressed lncRNAs and their nearby mRNAs by qPCR. Most of the differentially expressed mRNAs are closely connected with carbohydrate and lipid metabolisms in multiply cancers. Furthermore, part of them were validated in NPC and rhinitis tissues by qPCR. As a result, NR_047538, ENST00000442852, and fatty acid synthase (FASN) were closely associated with NPC. ZBTB7A had a positive association with NR_047538 and negative associations with ENST00000442852 and FASN. The results probably provide novel candidate biomarkers for NPC progression with different levels of ZBTB7A.

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.

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.

Interplay of Tumor Spread, Volume and Epstein-Barr Virus DNA in Nasopharyngeal Carcinoma: Feasibility of An Integrative Risk Stratification Scheme

Purpose: To investigate the inter-correlation of tumor spread, volume and quantitative plasma Epstein-Barr virus DNA level (pEBV DNA), and to further assess the prognostic efficacy of a novel risk stratification combining anatomic, volumetric and biological features in nasopharyngeal carcinoma (NPC).

Methods and Materials: One hundred and twelve patients with non-metastatic NPC were prospectively enrolled. Correlation of pEBV DNA with tumor invasiveness, lymph node (LN) metastasis, tumor volume and classification was tested by univariate and multivariate analyses. 5-year distant metastasis free survival (DMFS) was evaluated using Kaplan-Meier method and Cox proportional hazards model.

Results: Tumor volume, TNM stage and pEBV DNA were strongly inter-correlated to each other. Nodal volume, skull base invasion and LN metastasis to supraclavicular fossa were determined to be independent predictors for pEBV DNA level. To exclude collinearity, a risk stratification based on combination of EBV DNA, nodal volume and anatomic features was established, offering significant distinguishing ability in 5-year DMFS. Further multivariate Cox regression analysis found the novel stratification to be independent predictor of DMFS.

Conclusions: Both anatomic spread and tumor volume contribute to pEBV DNA level, leading to strong inter-correlation between NPC stage, volume and EBV DNA. The proposed risk stratification combining anatomic, volumetric and biological features showed potential in refining DMFS prediction.

External validity of a prognostic nomogram for locoregionally advanced nasopharyngeal carcinoma based on the 8th edition of the AJCC/UICC staging system: a retrospective cohort study

BACKGROUND

The tumor-node-metastasis (TNM) staging system does not perform well for guiding individualized induction or adjuvant chemotherapy for patients with locoregionally advanced nasopharyngeal carcinoma (NPC). We attempted to externally validate the Pan's nomogram, developed based on the 8th edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) staging system, for patients with locoregionally advanced disease. In addition, we investigated the reliability of Pan's nomogram for selection of participants in future clinical trials.

METHODS

This study included 535 patients with locoregionally advanced NPC who were treated between March 2007 and January 2012. The 5-year overall survival (OS) rates were calculated using the Kaplan-Meier method and compared with predicted outcomes. The calibration was tested using calibration plots and the Hosmer-Lemeshow test. Discrimination ability, which was assessed using the concordance index, as compared with other predictors.

RESULTS

Pan's nomogram was observed to underestimate the 5-year OS of the entire cohort by 8.65% [95% confidence interval (CI) - 9.70 to - 7.60%, P < 0.001] and underestimated the 5-year OS of each risk group. The differences between the predicted and observed 5-year OS rates were smallest among low-risk patients (< 135 points calculated using Pan's nomogram; which predicted minus observed OS, - 6.41%, 95% CI - 6.75 to - 6.07%, P < 0.001) and were largest among high-risk patients (≥ 160 points) (- 13.56%, 95% CI - 15.48 to - 11.63%, P < 0.001). The Hosmer-Lemeshow test suggested that the predicted and observed 5-year OS rates had no ideal relationship (P < 0.001). Pan's nomogram had better discriminatory ability compared with the levels of Epstein-Barr virus DNA acid (EBV DNA) and the 7th or 8th AJCC/UICC staging system, although not better compared with the combination of EBV DNA and the 8th staging system. Additionally, Pan's nomogram was marginally inferior to our predictive model, which included the 8th AJCC/UICC N-classification, age, gross primary tumor volume, lactate dehydrogenase, and body mass index.

CONCLUSIONS

Pan's nomogram underestimated the 5-year OS of patients with locoregionally advanced NPC at our cancer center, and may not be a precise tool for selecting participants for clinical trials.

The plasma Epstein-Barr virus DNA level guides precision treatment for nasopharyngeal carcinoma in the intensity-modulated radiotherapy era: a large population-based cohort study from an endemic area

Background:

In the intensity-modulated radiotherapy (IMRT) era, the survival benefit of concurrent chemotherapy for locoregionally advanced nasopharyngeal carcinoma (LA-NPC) remains undetermined. This study aimed to evaluate the benefits of IMRT with concurrent chemotherapy compared with IMRT alone for LA-NPC patients with different plasma Epstein–Barr virus (EBV) DNA levels.

Methods:

Patients were identified from a prospectively maintained database in an endemic area between November 2002 and December 2013. Cox proportional hazards models, propensity score matching, and inverse probability weighting models were established for survival analysis. Stratification analysis was performed based on interaction effects analysis. Finally, sensitivity analysis was performed considering unmeasured confounders.

Results:

A total of 1357 eligible patients were enrolled (median follow up 62.4 months; range 3.5–155.8 months). No significant survival differences were observed between groups in the entire cohort. Notably, a significant interaction effect was observed between treatment regimens and EBV DNA levels. In patients with high EBV DNA levels (>4000 copies/ml), all three models showed that IMRT with concurrent chemotherapy significantly improved overall survival [hazard ratio (HR) 2.521, 95% confidence interval (CI) 1.218–5.216], disease-free survival (HR 2.168, 95% CI 1.349–3.483), and distant metastasis-free survival (HR 2.331, 95% CI 1.194–4.551) compared with IMRT alone. No differences were found in patients with low EBV DNA levels. Sensitivity analysis confirmed the robustness of the results.

Conclusion:

In the IMRT era, concurrent chemotherapy treatment of LA-NPC patients with high EBV DNA levels is reasonable. However, the optimal regimen for LA-NPC patients with low EBV DNA levels needs further validation in randomized clinical trials.

Integrated Diagnostic Model That Incorporates Epstein-Barr Virus DNA, Imaging, and Nasal Endoscopy to Stratify Primary Tumor and Lymph Nodes in a Patient with N1 Nasopharyngeal Carcinoma: Multidisciplinary Management

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy, with a high metastatic potential. Epstein-Barr virus (EBV) infection plays a fundamental role, even if it is not well understood. The diagnosis of the disease in its early stage is infrequent. Imaging studies, positron emission tomography scans in addition to clinical examination, endoscopic examination, and biopsy provide information on the extent of the disease. The application of neoadjuvant chemotherapy followed by concomitant chemoradiation can improve the control of NPC. In March 2016, a 54-year-old male with NPC cT1 cN2 cM0, stage III (8th edition of American Joint Committee on Cancer (AJCC) staging system) underwent to a two-step treatment: induction chemotherapy by TPF regimen (docetaxel, cisplatin, 5-fluorouracil), followed by concomitant chemoradiotherapy (weekly cisplatin). The quantity of free plasma EBV-DNA can be related to the disease stage, and the detection of EBV-DNA during follow-up can be predictive of distant metastases. Especially, either plasma or serum EBV-DNA titer is estimated to reflect tumor volume. Biologically, such EBV-DNA reflects reproduced or released DNA from dead or dying tumor cells. On the other hand, EBV-specific DNA released as exosome may reflect the biological feature of the alive NPC tumor cell. The follow-up is ongoing after 21 months from a complete response.

Circulating pre-treatment Epstein-Barr virus DNA as prognostic factor in locally-advanced nasopharyngeal cancer in a non-endemic area

The prognostic value of pre-treatment Epstein-Barr Virus (EBV) DNA viral load for non-endemic, locally-advanced, EBV-related nasopharyngeal cancer (NPC) patients is yet to be defined. All patients with EBV encoded RNA (EBER)-positive NPC treated at our Institution from 2005 to 2014 with chemotherapy (CT) concurrent with radiation (RT) +/- induction chemotherapy (ICT) were retrospectively reviewed. Pre-treatment baseline plasma EBV DNA (b-EBV DNA) viral load was detected and quantified by PCR. Median b-EBV DNA value was correlated to potential influencing factors by univariate analysis. Significant variables were then extrapolated and included in a multivariate linear regression model. The same variables, including b-EBV DNA, were correlated with Disease Free Survival (DFS) and Overall Survival (OS) by univariate and multivariate analysis.

A total of 130 locally-advanced EBER positive NPC patients were evaluated. Overall, b-EBV DNA was detected in 103 patients (79.2%). Median viral load was 554 copies/mL (range 50–151075), and was positively correlated with T stage (p=0.002), N3a-b vs N0-1-2 stage (p=0.048), type of treatment (ICT followed by CTRT, p=0.006) and locoregional and/or distant disease recurrence (p=0.034). In the overall population, DFS and OS were significantly longer in patients with pre-treatment negative EBV DNA than in positive subjects at the multivariate analysis.

Negative b-EBV DNA can be considered as prognostic biomarker of longer DFS and OS in NPC in non-endemic areas. This finding needs confirmation in larger prospective series, with standardized and inter-laboratory harmonized method of plasma EBV DNA quantification.

Dynamic changes in plasma Epstein-Barr virus DNA load during treatment have prognostic value in nasopharyngeal carcinoma: a retrospective study

Circulating plasma Epstein-Barr virus DNA (EBV DNA) is related to tumor recurrence and metastasis and has potential as a dynamic, sensitive, and specific marker in nasopharyngeal carcinoma (NPC). We investigated the clinical significance of assessing plasma EBV DNA load at various time points during treatment. Patients with NPC (n = 949) for whom plasma EBV DNA load was measured by real-time quantitative polymerase chain reaction (RT-qPCR) before treatment (pre-EBV) and at midtreatment (mid-EBV), end of treatment (end-EBV), and 3 months after completing treatment (3 m-EBV) were retrospectively assessed. Receiver operating characteristic (ROC) curve analysis was used to identify the optimal EBV DNA cutoff point for each time point. Overall survival (OS), distant metastasis-free survival (DMFS), and progression-free survival (PFS) were compared using Kaplan-Meier estimates. High pre-EBV, high mid-EBV, high end-EBV, and high 3 m-EBV were all associated with significantly poorer OS, DMFS, and PFS in the entire cohort. Detectable end-EBV and 3 m-EBV was associated with significantly poorer OS, DMFS, and PFS. Among patients with detectable end-EBV, adjuvant therapy significantly improved OS (HR 2.419; 95% CI 1.297-4.51, P = 0.03) and DMFS (HR 2.45; 95% CI 1.243-4.828, P = 0.04), but not PFS (P = 0.17). EBV DNA represents a dynamic biomarker for monitoring treatment and predicting survival in NPC. Assessing plasma EBV DNA before, during, and after chemoradiotherapy could be clinically valuable and enable selection of patients most likely to benefit from additional therapy and improve assessment of treatment response and disease surveillance. Further multicenter prospective investigations are warranted.

Cisplatin suppresses proliferation, migration and invasion of nasopharyngeal carcinoma cells in vitro by repressing the Wnt/β-catenin/Endothelin-1 axis via activating B cell translocation gene 1

PURPOSE

Nasopharyngeal carcinoma (NPC) is one of the most commonly diagnosed cancers worldwide with significantly high prevalence in Southern China. Chemoprevention of cancer with alkylating agent compounds could potentially reverse, suppress, or prevent cancer progression. Cisplatin (CIS) is an antineoplastic or cytotoxic platinum-based drug used for chemotherapy of different types of human cancers such as NPC. Nevertheless, the effects of CIS on the migration and invasion of human NPC cells and the underlying molecular mechanisms have not yet been fully scrutinized.

METHODS

In this work, we tested the effect of CIS on the proliferation, migration and invasion of NPC cells. The results exhibited that this drug exerts remarkable inhibitory effects on the proliferation, migration and invasion of NPC cells in a dose-dependent manner. Western blotting and real time RT-PCR were used for expression analyses.

RESULTS

We found that CIS treatment led to a dose-dependent inhibition of Endothelin-1 (ET1) expression, at protein as well as mRNA levels in NPC cells. CIS was also found to activate the expression of BTG1 in NPC cells. Moreover, mechanistic analyses revealed that CIS increased the expression of B cell translocation gene 1 (BTG1) to suppress the expression of ET1. Furthermore, we show that ET1 could not be induced in CIS-resistant cells with suppressed BTG1 expression, and subsequently demote the proliferation, migration and invasion of NPC cells.

CONCLUSIONS

These findings provided compelling evidence of the role of CIS in suppressing NPC metastasis and its underlying molecular mechanisms.

Prognostic values of the integrated model incorporating the volume of metastatic regional cervical lymph node and pretreatment serum Epstein-Barr virus DNA copy number in predicting distant metastasis in patients with N1 nasopharyngeal carcinoma

Background

According to the 7th edition of the American Joint Committee on Cancer (AJCC) staging system, over 50% of patients with nasopharyngeal carcinoma (NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node (GTVnd) and pretreatment serum copy number of Epstein–Barr virus (EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients.

Methods

The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic (ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan–Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model.

Results

The 5-year distant metastasis-free survival (DMFS) rates for patients with GTVnd > 18.9 vs. ≤ 18.9 mL were 82.2% vs. 93.2% (P < 0.001), and for patients with EBV DNA copy number > 4000 vs. ≤ 4000 copies/mL were 83.5% vs. 93.9% (P < 0.001). After adjusting for GTVnd, EBV DNA copy number, and T category in the Cox regression model, both GTVnd > 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis (both P < 0.05). According to combination of GTVnd and EBV DNA copy number, all patients were divided into low-, moderate-, and high-risk groups, with the 5-year DMFS rates of 96.1, 87.4, and 73.8%, respectively (P < 0.001). Multivariate analysis confirmed the prognostic value of this model for distant metastatic risk stratification (hazard ratio [HR], 4.17; 95% confidence interval [CI] 2.34–7.59; P < 0.001).

Conclusions

GTVnd and serum EBV DNA copy number are independent prognostic factors for predicting distant metastasis in NPC patients with N1 disease. The prognostic model incorporating GTVnd and EBV DNA copy number may improve metastatic risk stratification for this group of patients.

Validation and comparison of the 7th and 8th edition of AJCC staging systems for non-metastatic nasopharyngeal carcinoma, and proposed staging systems from Hong Kong, Guangzhou, and Guangxi

OBJECTIVES

We aimed to validate and compare the 7th and 8th edition of AJCC staging systems for non-metastatic nasopharyngeal carcinoma, and proposed staging systems from Hong Kong, Guangzhou, and Guangxi.

MATERIALS AND METHODS

We retrospectively included 899 patients treated between November 5, 2002 and May 27, 2010. Separation and discrimination of each staging system in overall survival were primarily compared.

RESULTS

Compared with the 7th AJCC, the 8th AJCC and all proposed staging systems well separated across T-classification. T-classification from Guangzhou seemed to perform best in discrimination (C-index 0.6454), followed by the 8th AJCC (0.6451), the 7th AJCC (0.6386), Hong Kong (0.6376) and Guangxi (0.5889). For N-classification, no staging systems improved the weakness of the 7th AJCC in separating N2 and N1, except that suggestion from Guangzhou showed higher potential (P=0.096). Besides, N-classification from Guangzhou had a C-index of 0.6444, larger than that of the 8th AJCC (0.6235), the 7th AJCC (0.6179), Hong Kong (0.6175) and Guangxi (0.6175). Accordingly, stage group of staging system from Guangzhou showed higher discrimination (C-index 0.6839), compared with the 8th AJCC (0.6791), the 7th AJCC (0.6766), Hong Kong (0.6765) and Guangxi (0.6688), despite that stage I and II remained inseparable (P=0.322).

CONCLUSIONS

The 8th AJCC staging system appeared to be better than the 7th AJCC. But the proposed staging system from Guangzhou was more likely to improve the separation and discrimination abilities.

Dosimetric comparison and observation of three-dimensional conformal radiotherapy for recurrent nasopharyngeal carcinoma

The aim of the study was to investigate the effect of three-dimensional conformal radiation therapy (3D-CRT) on nasopharyngeal carcinoma (NPC) and the incidence of complications. Between May 2010 and June 2012, 141 patients diagnosed with local recurrence of NPC due to cranial base lesions or cranial nerve symptoms, confirmed by pathology biopsy and/or by CT/MRI, were included in the present study. In accordance with the principle of randomized control, the patients were divided into three groups and treated with three different doses of 3D-CRT. The planned radiotherapy doses of 3D-CRT were 58/1.8–2 Gy, 62/1.8–2 Gy and 68/1.8–2 Gy, respectively. The survival rate, disease-free survival (DFS) rate and local control rate of the three groups of patients were compared as well as the adverse reactions observed after radiotherapy. The prognoses of NPC patients were analyzed by univariate and multivariate analyses. The follow-up rate of the study was 100%. The 5-year overall survival, DFS, and locoregional recurrence-free survival rates were: 43.2 vs. 64.53 vs. 75%, 29.13 vs. 42.82 vs. 39.7% and 30.76 vs. 44.19 vs. 45.4%, respectively. In addition, 62/1.8–2 Gy was similar in treatment effects to 68/1.8–2 Gy, but 68/1.8–2 Gy showed more adverse reactions than 62/1.8–2 Gy. Thus, 62/1.8–2 Gy can be used as a safe and effective dose for 3D-CRT treatment of NPC. Univariate and multivariate analyses showed that age may be the main prognostic factor of patients with NPC. In conclusion, 3D-CRT with a dose of 62/1.8–2 Gy is a safe, effective and tolerable treatment for NPC patients with good clinical value.