Influence of Cervical Node Necrosis of Different Grades on the Prognosis of Nasopharyngeal Carcinoma Patients Treated with Intensity-Modulated Radiotherapy

Matted Lymph Nodes on MRI in Nasopharyngeal Carcinoma: Prognostic Factor and Potential Indication for Induction Chemotherapy Benefits

BACKGROUND

Lymph node characteristics markedly affect nasopharyngeal carcinoma (NPC) prognosis. Matted node (MN), an important characteristic for lymph node, lacks explored MRI-based prognostic implications.

PURPOSE

Investigate MRI-determined MNs' prognostic value in NPC, including 5-year overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival (LRFS), progression-free survival (PFS), and its role in induction chemotherapy (IC).

STUDY TYPE

Retrospective cohort survival study.

POPULATION

Seven hundred ninety-two patients with non-metastatic NPC (female: 27.3%, >45-year old: 50.1%) confirmed by biopsy.

FIELD STRENGTH/SEQUENCE

5-T/3.0-T, T1-, T2- and post-contrast T1-weighted fast spin echo sequences acquired.

ASSESSMENT

MNs were defined as ≥3 nodes abutting with intervening fat plane replaced by extracapsular nodal spread (ENS). Patients were observed every 3 months for 2 years and every 6 months for 5 years using MRI. Follow-up extended from treatment initiation to death or final follow-up. MNs were evaluated by three radiologists with inter-reader reliability calculated. A 1:1 matched-pair method compared survival differences between MN-positive patients with or without IC. Primary endpoints (OS, DMFS, LRFS, PFS) were calculated from therapy initiation to respective event.

STATISTICAL TESTS

Kappa values assessed inter-reader reliability. Correlation between MN, ENS, and LNN was studied through Spearman's correlation coefficient. Clinical characteristics were calculated via Fisher's exact, Chi-squared, and Student's t-test. Kaplan-Meier curves and log-rank tests analyzed all time-to-event data. Confounding factors were included in Multivariable Cox proportional hazard models to identify independent prognostic factors. P-values <0.05 were considered statistically significant.

RESULTS

MNs incidence was 24.6%. MNs independently associated with decreased 5-year OS, DMFS, and PFS; not LRFS (P = 0.252). MN-positive patients gained significant survival benefit from IC in 5-year OS (88.4% vs. 66.0%) and PFS (76.4% vs. 53.5%), but not DMFS (83.1% vs. 69.9%, P = 0.145) or LRFS (89.9% vs. 77.8%, P = 0.140).

DATA CONCLUSION

MNs may independently stratify NPC risk and offer survival benefit from IC.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Radiologic extranodal extension for nodal staging in nasopharyngeal carcinoma

PURPOSE

Extranodal extension (ENE) has the potential to add value to the current nodal staging system (N8th) for predicting outcome in nasopharyngeal carcinoma (NPC). This study aimed to incorporate ENE, as well as cervical nodal necrosis (CNN) to the current stage N3 and evaluated their impact on outcome prediction. The findings were validated on an external cohort.

METHODS & MATERIALS

Pre-treatment MRI of 750 patients from the internal cohort were retrospectively reviewed. Predictive values of six modified nodal staging systems that incorporated four patterns of ENE and two patterns of CNN to the current stage N3 for disease-free survival (DFS) were compared with that of N8th using multivariate cox-regression and concordance statistics in the internal cohort. Performance of stage N3 for predicting disease recurrence was calculated. An external cohort of 179 patients was used to validate the findings.

RESULTS

Incorporation of advanced ENE, which infiltrates into adjacent muscle/skin/salivary glands outperformed the other five modifications for predicting outcomes (p < 0.01) and achieved a significantly higher c-index for 5-year DFS (0.69 vs 0.72) (p < 0.01) when compared with that of N8th staging system. By adding advanced ENE to the current N3 increased the sensitivity for predicting disease recurrence from 22.4 % to 47.1 %. The finding was validated in the external cohort (5-year DFS 0.65 vs. 0.72, p < 0.01; sensitivity of stage N3 increased from 14.0 % to 41.9 % for disease recurrence).

CONCLUSION

Results from two centre cohorts confirmed that the radiological advanced ENE should be considered as a criterion for stage N3 disease in NPC.

Efficacy of induction chemotherapy in lymph node-positive stage III nasopharyngeal carcinoma and identification of beneficiaries based on clinical features: A propensity score matching analysis

PURPOSE

To investigate the role of induction chemotherapy (IC) in lymph node-positive (LN-positive) stage III nasopharyngeal carcinoma (NPC) receiving concurrent chemoradiotherapy (CCRT).

METHODS

In total, 627 patients with newly diagnosed LN-positive stage III NPC receiving CCRT or IC plus CCRT were included. The primary endpoint was progression-free survival (PFS). Propensity-score matching (PSM) was conducted to balance the intergroup covariates. Kaplan-Meier method with log-rank test was employed to compare survival curves. Subgroup analyses were conducted based on baseline characteristics.

RESULTS

After 1:1 PSM, 414 patients were identified (207 patients per group). Compared with CCRT, IC plus CCRT provided better survival (5-year PFS 88.4% vs. 78.6%, P = 0.01; overall survival [OS] 94.8% vs. 85.3%, P = 0.003; and distant metastasis-free survival [DMFS] 93.1% vs. 85.6%, P = 0.03). The IC beneficial effects on PFS were mainly present in patients with grade 2-3 ENE, elevated serum lactate dehydrogenase (LDH > 170U/L), and N2 disease. Patients with grade 2 CNN had comparable PFS benefits to those with grade 0-1 CNN. For patients with grade 0-1 ENE combined with LDH ≤ 170U/L, survival between the two groups was similar with 5-year PFS 93.6% vs. 90.4% (P = 0.50), OS 94.2% vs. 93.0% (P = 0.72), and DMFS 98.6% vs. 97.7% (P = 0.98).

CONCLUSION

Adding IC before CCRT improved survival in LN-positive stage III NPC patients. Additional IC did not provide better survival for patients with grade 0-1 ENE combined with LDH ≤ 170U/L and could be avoided in this population. CNN may not be a good risk factor for tailoring a personalized treatment plan.

Integrating pretreatment MRI-detected nodal features and Epstein-Barr virus DNA to identify optimal candidates for intensity-modulated radiotherapy alone in patients with stage II nasopharyngeal carcinoma

OBJECTIVES

To develop and validate a prognostic nomogram based on MRI-detected features of retropharyngeal and cervical lymph nodes and Epstein-Barr virus (EBV) DNA in patients with stage II nasopharyngeal carcinoma (NPC) to distinguish low-risk patients for whom intensity-modulated radiotherapy (IMRT) alone is sufficient.

METHODS

This retrospective study enrolled 894 patients with stage II NPC (596 and 298 in the training and validation cohorts, respectively) with pretreatment MRI between August 2010 and May 2019. All patients received IMRT with or without additional chemotherapy. We identified independent risk factors using univariate and multivariate Cox regression analyses. Survival was compared using Kaplan-Meier curves with the log-rank test.

RESULTS

Independent factors derived from the multivariate analysis include cervical nodal necrosis (CNN), the extracapsular spread (ECS) of cervical and retropharyngeal lymph nodes, and gamma-glutamyl transferase (γ-GGT). Nomograms A, B, and C were established based on the clinical [tumor-node-metastasis (TNM) stage + Epstein-Barr virus (EBV) DNA], the clinical-radiological [all independent predictors] and the combined models [the clinical-radiological model + EBV DNA], respectively. Nomogram C (C-index 0.769 [0.718-0.820]) demonstrated better risk discrimination than nomogram B (0.762 [0.715-0.809]), nomogram A (0.619 [0.564-0.674]), and the TNM stage (0.560 [0.509-0.611]). In the low-risk group divided by nomogram C, no significant survival differences were observed between patients treated with radiotherapy (RT) alone and other regimens including additional chemotherapy.

CONCLUSIONS

The nomogram combining MRI-detected retropharyngeal and cervical lymph node features with pretreatment EBV-DNA improved the prognostic risk stratification for stage II NPC.

Prognostic nomograms for nasopharyngeal carcinoma with nodal features and potential indication for N staging system: Validation and comparison of seven N stage schemes

PURPOSE

To identify the prognostic value of the nodal features, propose a nomogram-based N stage system and evaluate the performance of seven N stage schemes of nasopharyngeal carcinoma (NPC) patients.

METHODS

Data from 1638 non-distant metastatic NPC patients were used to develop nomograms predicting 3-year and 5-year overall survival (OS) and distant metastasis-free survival (DMFS). Based on nomogram and multivariate analyses, a new N-stage scheme was proposed. The performance of the nomogram-based N staging system was assessed against five newly proposed N staging systems and the current 8th N staging system using a quantitative model to compare hazard consistency, discrimination, outcome prediction, and sample size balance. The Kaplan-Meier method with log-rank tests was used to compare survival differences.

RESULTS

Nomograms to predict OS and DMFS were constructed using extranodal extension infiltrating the surrounding structures (ENEmax), maximal axial diameter (MAD), large retropharyngeal lymph nodes (RLN, minimal axial diameter > 1.5 cm), multiple central nodal necrosis (CNN), and total lymph node (LN) number and level. Multivariate analysis showed the independent prognostic value of ENEmax and MAD > 3 cm for all selected survival endpoints (p < 0.05). Large RLN and lower neck involvement were independently associated with OS (p < 0.05). We proposed using a large RLN and MAD > 3 cm as N2 factors, and ENEmax and lower neck involvement as N3 factors. Among the seven N-stage schemes, our nomogram-based N scheme and ENEmax to N3 scheme (ENE3) ranked in the top two in the overall comparison with the elevated outcome predicting value (highest c-index). However, between the N0, N1, N1, and N2 subgroups, the ENE3 scheme showed no difference in OS or DMFS (p > 0.05).

CONCLUSION

The predictive model highlighted the independent prognostic value of ENEmax, cervical lymph node, MAD, and large RLN, which can be used as criteria for future N staging.

Prognostic Value of Lymph Node Necrosis at Different N Stages in Patients with Nasopharyngeal Carcinoma

Background: Lymph node necrosis (LNN), including retropharyngeal nodal necrosis and cervical nodal necrosis, which is related to radiotherapy/ chemotherapy resistance, is a common phenomenon in nasopharyngeal carcinoma (NPC). This study was to assess the prognostic value of LNN at different N stages in NPC patients. Materials and Methods: In total, 1,665 newly diagnosed NPC patients at stage TxN1-3M0 from two centers were enrolled. Univariate and multivariate models were constructed to assess the association between LNN and long-term survival outcomes. The propensity score matching method was performed to balance treatment groups for baseline characteristics. Results: Of the 1,665, 540 patients (540/1665, 32.4%) were diagnosed with LNN, of which 54.1% (292/540) patients were at stage N1, 31.3% (169/540) at stage N2, and 14.6% (79/540) at stage N3. Univariate and multivariate analyses indicated LNN as an independent predictor for progression‑free survival (PFS), overall survival (OS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS) in stage N1-3 patients (all P<0.001). When patients were analyzed according to stage, similar findings were observed for N1 patients (all P<0.001); for N2 patients, LNN independently predicted PFS (P=0.003), OS (P=0.011), and DMFS (P=0.004), and for stage N3, LNN only independently predicted LRRFS (P=0.019). 123 pairs of patients who received induction chemotherapy plus concurrent chemoradiotherapy or only concurrent chemoradiotherapy were matched, adding induction chemotherapy improved 5-year OS, PFS and LRFFS, but the results were not statistically significant. Conclusions: In NPC patients, LNN could independently predict poor prognosis at all N1-3 stages and at each N stage (N1 to N3). The value of adding induction chemotherapy to concurrent chemoradiotherapy in patients with LNN still requires further prospective studies.

Intra- and peritumoral MRI radiomics assisted in predicting radiochemotherapy response in metastatic cervical lymph nodes of nasopharyngeal cancer

BACKGROUND

To establish and validate radiomic models combining intratumoral (Intra) and peritumoral (Peri) features obtained from pretreatment MRI for the prediction of treatment response of lymph node metastasis from nasopharyngeal cancer (NPC).

METHODS

One hundred forty-five NPC patients (102 in the training and 43 in the validation set) were retrospectively enrolled. Radiomic features were extracted from Intra and Peri regions on the metastatic cervical lymph node, and selected with the least absolute shrinkage and selection operator (LASSO). Multivariate logistic regression analysis was applied to build radiomic models. Sensitivity, specificity, accuracy, and the area under the curve (AUC) of receiver operating characteristics were employed to evaluate the predictive power of each model.

RESULTS

The AUCs of the radiomic model of Intra, Peri, Intra + Peri, and Clinical-radiomic were 0.910, 0.887, 0.934, and 0.941, respectively, in the training set and 0.737, 0.794, 0.774, and 0.783, respectively, in the validation set. There were no significant differences in prediction performance among the radiomic models in the training and validation sets (all P > 0.05). The calibration curve of the radiomic model of Peri demonstrated good agreement between prediction and observation in the training and validation sets.

CONCLUSIONS

The pretreatment MRI-based radiomics model may be useful in predicting the treatment response of metastatic lymph nodes of NPC. Besides, the generalization ability of the radiomic model of Peri was better than that of Intra and Intra + Peri.

Prognostic significance of cervical radiologic carotid artery invasion by lymph node on magnetic resonance imaging in nasopharyngeal carcinoma

PURPOSE

Carotid artery invasion (CAI) has been demonstrated to be an important prognosticator in some head and neck cancers. This study aimed to examine the prognostic value of radiologic CAI (rCAI) by cervical lymphadenopathy in nasopharyngeal carcinoma (NPC).

METHODS

NPC patients treated between January 2013 and December 2016 were included. Pre-treatment MRIs were reviewed for cervical rCAI according to the radiologic criteria. Univariate and multivariate models were constructed to assess the association between cervical rCAI and clinical outcomes. A new N classification system was proposed and compared to the 8th AJCC system.

RESULTS

The percentage of patients with MRI-positive lymph nodes was 84.7% (494/583), of whom cervical rCAI cases accounted for 42.3% (209/494). Cervical rCAI was associated with significantly poorer OS, DFS, DFFS and RFFS compared to non-rCAI (P < 0.05). Multivariate analyses confirmed that cervical rCAI was an independent prognosticator for DFS and DFFS, surpassing other nodal features, such as laterality, size, cervical node necrosis (CNN) and radiologic extranodal extension (rENE), while location of positive LNs remained independently associated with OS, DFS and DFFS. We propose a refined N classification: New_N1: upper neck LNs only without cervical rCAI; New_N2: upper neck LNs only with cervical rCAI; New_N3: upper and lower LNs. The proposed classification broadened the differences in OS, DFS and DFFS between N1 and N2 disease, and achieved a higher c-index for DFS and DFFS.

CONCLUSIONS

Cervical rCAI was an independent unfavorable indicator of NPC. Compared to the AJCC system, the proposed N category showed satisfactory stratification between N1 and N2 disease, and better prediction of distant metastasis and disease failure.

Prognostic generalization of multi-level CT-dose fusion dosiomics from primary tumor and lymph node in nasopharyngeal carcinoma

PURPOSE

To investigate the prognostic performance of multi-level computed tomography (CT)-dose fusion dosiomics at the image-, matrix-, and feature-levels from the gross tumor volume (GTV) at nasopharynx and the involved lymph node for nasopharyngeal carcinoma (NPC) patients.

METHODS

Two hundred and nineteen NPC patients (175 vs. 44 for training vs. internal validation) were used to train prediction model, and 32 NPC patients were used for external validation. We first extracted CT and dose information from intratumoral nasopharynx (GTV_nx) and lymph node (GTV_nd) regions. Then, the corresponding peritumoral regions (RING_3 mm and RING_5 mm) were also considered. Thus, the individual and combination of intratumoral and peritumoral regions were as follows: GTV_nx, GTV_nd, RING_3 mm_nx, RING_3 mm_nd, RING_5 mm_nx, RING_5 mm_nd, GTV_nxnd, RING_3 mm_nxnd, RING_5 mm_nxnd, GTV + RING_3 mm_nxnd, and GTV + RING_5 mm_nxnd. For each region, 11 models were built by combining five clinical parameters and 127 features from: (1) dose images alone; (2-7) fused dose and CT images via wavelet-based fusion using CT weights of 0.2, 0.4, 0.6, and 0.8, gradient transfer fusion, and guided-filtering-based fusion (GFF); (8) fused matrices (sumMat); (9-10) fused features derived via feature averaging (avgFea) and feature concatenation (conFea); and finally, (11) CT images alone. The concordance index (C-index) and Kaplan-Meier curves with log-rank test were used to assess model performance.

RESULTS

The fusion models' performance was better than single CT/dose model on both internal and external validation. Models that combined the information from both GTV_nx and GTV_nd regions outperformed the single region model. For internal validation, GTV + RING_3 mm_nxnd GFF model achieved the highest C-index both in recurrence-free survival (RFS) and metastasis-free survival (MFS) predictions (RFS: 0.822; MFS: 0.786). The highest C-index in external validation set was achieved by RING_3 mm_nxnd model (RFS: 0.762; MFS: 0.719). The GTV + RING_3 mm_nxnd GFF model is able to significantly separate patients into high-risk and low-risk groups compared to dose-only or CT-only models.

CONCLUSION

Fusion dosiomics model combining the primary tumor, the involved lymph node, and 3 mm peritumoral information outperformed single-modality models for different outcome predictions, which is helpful for clinical decision-making and the development of personalized treatment.

Prognostic value of the cervical lymph node necrosis ratio in nasopharyngeal carcinoma

PURPOSE

Whether cervical lymph node necrosis (CNN) is an independent adverse prognostic factor in nasopharyngeal carcinoma (NPC) has not been determined. In this study, the CNN ratio was graded quantitatively to explore the prognostic value in NPC.

PARTICIPANTS AND METHODS

We retrospectively reviewed a total of 648 pathologically confirmed as NPC. We outlined metastatic lymph nodes and necrotic area of lymph nodes slice by slice on the magneticresonanceimages (MRI) cross section, and calculated the corresponding CNN ratio.

RESULTS

The median CNN ratio (17.37 %) was taken as the cut-off point, 256 (39.51 %) patients were divided into CNN1 group (<17.37 %, n = 128) and CNN2 group (≥17.37 %, n = 128), 392 (60.49 %) patients without lymph nodes necrosis were CNN0. Among the CNN0, CNN1 and CNN2 groups, five-year overall survival (OS) was 82.4 %, 76.6 % and 71.1 %, locoregional recurrence-free survival (LRRFS) was 91.3 %, 91.1 % and 90.5 %, distant metastasis-free survival (DMFS) was 83.7 %, 78.5 % and 68.7 %, progression-free survival (PFS) was 78.3 %, 71.7 % and 61.6 % respectively. By multivariate analysis, CNN was an independent prognostic factor for OS (P = 0.003), DMFS (P = 0.019) and PFS (P = 0.007). More than 3 cycles of chemotherapy significantly increased OS (P = 0.024) and DMFS (P = 0.015) in the CNN1 group.

CONCLUSIONS

This study indicated that CNN is one of the factors with the negative prognosis of NPC. The CNN ratio might be used as one of the reference factors in the formulation of individualized treatment plan.

Prognostic value of quantitative cervical nodal necrosis burden on MRI in nasopharyngeal carcinoma and its role as a stratification marker for induction chemotherapy

OBJECTIVES

This study aimed to assess the prognostic value of quantitative cervical nodal necrosis (CNN) burden in N staging risk stratification in patients with nasopharyngeal carcinoma.

METHODS

Univariate and multivariate Cox regression models evaluated the association between lymph node variables based on MRI images and survival. Revisions for the N classification system were proposed and compared to the 8th edition AJCC staging system using Harrell's concordance index (C-index). The survival outcomes of induction chemotherapy plus concurrent chemoradiotherapy (CCRT) and CCRT alone in patients with multiple CNNs were compared.

RESULTS

In 1319 patients enrolled, CNN was not an independent prognostic factor for the main survival outcomes, but multiple CNNs (three or more necrotic nodes) were independent prognostic factors for distant metastasis-free survival (DMFS) (adjusted hazard ratio [HR], 2.05; p = 0.020) and progression-free survival (PFS) (HR, 1.78; p = 0.004), surpassing other nodal variables. On upgrading patients with multiple CNNs to revised N3 disease, the proposed N staging widened the differences in DMFS and PFS between N2 and N3 disease. The overall survival of patients with multiple CNNs who received CCRT plus induction chemotherapy was improved compared to that of those who received CCRT alone (76.1% vs. 55.7%; adjusted p = 0.030).

CONCLUSIONS

Upgrading patients with multiple CNNs to stage N3 may improve prognostication of the current AJCC staging system. Multiple CNNs might be a potential marker for stratifying patients who would benefit from induction chemotherapy.

KEY POINTS

• Quantitatively assessed the prognostic value of CNN burden in patients with NPC. • Upgrading patients with multiple CNNs to stage N3 may improve prognostication. • Multiple CNNs may be used as a stratification marker for induction chemotherapy.

Prognostic value of cervical nodal necrosis on staging imaging of nasopharyngeal carcinoma in era of intensity-modulated radiotherapy: a systematic review and meta-analysis

Purposes

To systematically review and perform meta-analysis to evaluate the prognostic value of cervical nodal necrosis (CNN) on the staging computed tomography/magnetic resonance imaging (MRI) of nasopharyngeal carcinoma (NPC) in era of intensity-modulated radiotherapy.

Methods

Literature search through PubMed, EMBASE, and Cochrane Library was conducted. The hazard ratios (HRs) with 95% confidence intervals (CIs) of CNN for distant metastasis-free survival (DMFS), disease free survival (DFS) and overall survival (OS) were extracted from the eligible studies and meta-analysis was performed to evaluate the pooled HRs with 95%CI.

Results

Nine studies, which investigated the prognostic values of 6 CNN patterns on MRI were included. Six/9 studies were eligible for meta-analysis, which investigated the CNN presence/absence in any nodal group among 4359 patients. The pooled unadjusted HRs showed that the CNN presence predicted poor DMFS (HR =1.89, 95%CI =1.72-2.08), DFS (HR =1.57, 95%CI =1.08-2.26), and OS (HR =1.87, 95%CI =1.69-2.06). The pooled adjusted HRs also showed the consistent results for DMFS (HR =1.34, 95%CI =1.17-1.54), DFS (HR =1.30, 95%CI =1.08-1.56), and OS (HR =1.61, 95%CI =1.27-2.04). Results shown in the other studies analysing different CNN patterns indicated the high grade of CNN predicted poor outcome, but meta-analysis was unable to perform because of the heterogeneity of the analysed CNN patterns.

Conclusion

The CNN observed on the staging MRI is a negative factor for NPC outcome, suggesting that the inclusion of CNN is important in the future survival analysis. However, whether and how should CNN be included in the staging system warrant further evaluation.

Cancer treatment evolution from traditional methods to stem cells and gene therapy

BACKGROUND

Cancer, a malignant tumor, is caused by the failure of the mechanism that controls cell growth and proliferation. Late clinical symptoms often manifest as lumps, pain, ulcers, and bleeding. Systemic symptoms include weight loss, fatigue, and loss of appetite. It is a major disease that threatens human life and health. How to treat cancer is a long-standing problem that needs to be overcome in the history of medicine.

METHOD

Traditional tumor treatment methods are poorly targeted, and the side effects of treatment seriously damage the physical and mental health of patients. In recent years, with the advancement of medical science and technology, the research on gene combined with mesenchymal stem cells to treat tumors has been intensified. Mesenchymal stem cells carry genes to target cancer cells, which can achieve better therapeutic effects.

DISCUSSION

In the text, we systematically review the cancer treatment evolution from traditional methods to novel approaches that include immunotherapy, nanotherapy, stem cell theapy, and gene therapy. We provide the latest review of the application status, clinical trials and development prospects of mesenchymal stem cells and gene therapy for cancer, as well as their integration in cancer treatment. Mesenchymal stem cells are effective carriers carrying genes and provide new clinical ideas for tumor treatment.

CONCLUSION

This review focuses on the current status, application prospects and challenges of mesenchymal stem cell combined gene therapy for cancer, and provides new ideas for clinical research.

The prognostic value of radiologic extranodal extension in nasopharyngeal carcinoma: Systematic review and meta-analysis

OBJECTIVES

The prognostic value of radiologic extranodal extension (rENE) in nasopharyngeal carcinoma remains controversial. In this study, a meta-analysis was performed to assess the prognostic value of ungraded rENE and unambiguous advanced rENE.

METHODS

A literature search through PubMed, Cochrane Library, EMBASE and manual searches was conducted until May 2021. The adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of overall survival and distant metastasis-free survival were extracted and pooled.

RESULTS

Nine eligible studies were published between 2012 and 2021. The pooled patient number was 7532 (range 61-1887). Seven studies were eligible for the analysis of ungraded rENE, while 3 studies were eligible for unambiguous advanced rENE. The results showed that ungraded rENE was associated with worse overall survival (HR 1.85, 95% CI 1.04-3.27) and significantly associated with worse distant metastasis-free survival (HR 2.07, 95% CI 1.36-3.13). On the other hand, unambiguous advanced rENE was significantly associated with worse overall survival (HR 2.62, 95% CI 2.12-3.25) and worse distant metastasis-free survival (HR 3.14, 95% CI 1.85-5.33).

CONCLUSIONS

In nasopharyngeal carcinoma, both ungraded and unambiguous advanced rENE are significant prognosticators of overall survival and distant metastasis-free survival. More prospective studies are required to determine its role in risk stratification or clinical staging.

The Value of Cervical Node Features in Predicting Long-Term Survival of Nasopharyngeal Carcinoma in the Intensity-Modulated Radiotherapy Era

Objective

To investigate the prognostic value of cervical node features in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) and build a prognostic nomogram to predict the long-term survival.

Methods

In this study, 1752 patients after IMRT from 2008 to 2011 were recruited. The clinical and laboratory characteristics and the nodal features including the nodal number, maximum dimension diameter, extranodal extension (ENE), and cervical node necrosis (CNN) were retrospective analyzed. Univariate Cox and multivariate proportional hazard regression models were used to test the prognostic value of nodal features. Prognostic nomograms were established to predict survival.

Results

The 10-year distant metastases-free survival (DMFS) and disease-specific survival (DSS) rates were 86.5% and 80.8%, respectively. Multivariate analysis showed that age, sex, lactate dehydrogenase (LDH), CNN, ENE, T stage, and N stage were independent factors for DSS. Two nomograms-nomogram A (without nodal features) and nomogram B (with nodal features)-were built. The calibration curve for the probability of DSS showed good agreement between prediction by nomogram and the actual observation. The C-index of nomogram B was higher than that for nomogram A in predicting DSS (0.708 vs 0.676, P<0.01).

Conclusion

The nodal features including ENE and CNN were negative prognostic factors for NPC, and the prognostic nomogram incorporating the nodal features was more accurate in predicting survival than the nomogram without nodal features.

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.

MRI-based radiomics as response predictor to radiochemotherapy for metastatic cervical lymph node in nasopharyngeal carcinoma

OBJECTIVE

To establish and substantiate MRI-based radiomic models to predict the treatment response of metastatic cervical lymph node to radiochemotherapy in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 145 consecutive patients with NPC were enrolled including 102 in primary cohort and 43 in validation cohort. Metastatic lymph nodes were diagnosed according to radiologic criteria and treatment response was evaluated according to the Response Evaluation Criteria in Solid Tumors. A total of 2704 radiomic features were extracted from contrast-enhanced T₁ weighted imaging (CE- T₁WI) and T₂ weighted imaging (T₂WI) for each patient, and were selected to construct radiomic signatures for CE-T₁WI, T₂WI, and combined CE-T₁WI and T₂WI, respectively. The area under curve (AUC) of receiver operating characteristic, sensitivity, specificity, and accuracy were used to estimate the performance of these radiomic models in predicting treatment response of metastatic lymph node.

RESULTS

No significant difference of AUC was found among radiomic signatures of CE-T₁WI, T₂WI, and combined CE-T₁WI and T₂WI in the primary and validation cohorts (all p > 0.05). For combined CE-T₁WI and T₂WI data set, 12 features were selected to develop the radiomic signature. The AUC, sensitivity, specificity, and accuracy were 0.927 (0.878-0.975), 0.911 (0.804-0.970), 0.826 (0.686-0.922), and 0.872 (0.792-0.930) in primary cohort, and were 0.772 (0.624-0.920), 0.792 (0.578-0.929), 0.790 (0.544-0.939), and 0.791 (0.640-0.900) in validation cohort.

CONCLUSION

MRI-based radiomic models were developed to predict the treatment response of metastatic cervical lymph nodes to radiochemotherapy in patients with NPC, which might facilitate individualized therapy for metastatic lymph nodes before treatment.

ADVANCES IN KNOWLEDGE

Predicting the response in patients with NPC before treatment may allow more individualizing therapeutic strategy and avoid unnecessary side-effects and costs. Radiomic features extracted from metastatic cervical lymph nodes showed promising application for predicting the treatment response in NPC.

Contemporary management of the neck in nasopharyngeal carcinoma

Up to 85% of the patients with nasopharyngeal carcinoma present with regional nodal metastasis. Although excellent nodal control is achieved with radiotherapy, a thorough understanding of the current TNM staging criteria and pattern of nodal spread is essential to optimize target delineation and minimize unnecessary irradiation to adjacent normal tissue. Selective nodal irradiation with sparing of the lower neck and submandibular region according to individual nodal risk is now emerging as the preferred treatment option. There has also been continual refinement in staging classification by incorporating relevant adverse nodal features. As for the uncommon occurrence of recurrent nodal metastasis after radiotherapy, surgery remains the standard of care.

Influence of tumor necrosis on treatment sensitivity and long-term survival in nasopharyngeal carcinoma

PURPOSE

To assess the impact of tumor necrosis on treatment sensitivity and long-term survival in patients with nasopharyngeal carcinoma (NPC) treated using intensity-modulated radiation therapy (IMRT).

PARTICIPANTS AND METHODS

In total, 757 patients with non-metastatic, histologically confirmed NPC were retrospectively examined. All patients were treated using IMRT; 93.7% patients with stage T3-T4/N1-N3 disease also received cisplatin-based chemotherapy.

RESULTS

The incidence rates of tumor necrosis in primary tumor, retropharyngeal lymph nodes, neck lymph nodes, and total tumor were 2%, 17.7%, 21.5%, and 31.4%. Overall, 40.8% patients with necrosis of the total tumor achieved complete response (CR) and 54.7% patients without tumor necrosis achieved CR at the end of treatment (χ² = 12.728, P < 0.001). The estimated 7-year overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS), and loco-regional relapse-free survival (LRRFS) for patients with tumor necrosis and without tumor necrosis of the total tumor were 68.5% vs. 88.4%, 70.5% vs. 88.1%, 77.6% vs. 90.6%, and 85.9% vs. 91.3%, respectively (all P < 0.001). Multivariate analyses indicated that necrosis of the total tumor was an independent predictor of OS, FFS, DMFS, and LRRFS. The impact of lymph node necrosis on long-term survival was similar to that of necrosis of the total tumor. ROC curves verified that inclusion of lymph node necrosis improved the predictive value of the current N classification criteria (P = 0.006).

CONCLUSIONS

Tumor necrosis served as a predictor of treatment sensitivity and poor prognosis for patients with NPC. Lymph node necrosis significantly improved the prognostic value of the current N classification criteria for NPC.

Pretreatment Photopenia on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Scans Predicts Poor Prognosis in Nasopharyngeal Cancer Patients Undergoing Concurrent Chemoradiotherapy

OBJECTIVES

To investigate the influence of pretreatment primary tumor or nodal photopenia (PP) on 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT), an indicator of tumor ischemia, on survival results of nasopharyngeal cancers (NPCs) treated with concurrent chemoradiotherapy (C-CRT).

METHODS

The pre-C-CRT FDG PET-CT scans of 104 patients with NPC (cT1-4 N0-3 M0) were retrospectively examined to determine the presence of PP (PP+). Our primary endpoint was the influence of PP+ on overall survival (OS), while the progression-free survival (PFS) and locoregional PFS (LRPFS) constituted the secondary endpoints.

RESULTS

The PP+ was detected in 29 (27.9%): nine (8.7%), seven (6.7%), and 13 (12.5%) in the primary tumor alone, primary tumor plus neck nodes, and neck nodes alone, respectively. Because the PP+ cases were small by count per location, all comparative analyses were performed according to overall PP+/ PP- status instead of per detected site. At a median follow-up of 67.8 months (range, 9 to 130 months), the median survival times were not reached (NR) for the entire population, while 5-year OS, LRPFS, and PFS rates were 73.3%, 68.2%, and 63.4%, respectively. Comparatively the PP+ patients exhibited significantly poorer median OS (49.8 months vs. NR, P<0.001), LRPFS (40.7 months vs. NR, P=0.001), and PFS (31.8 months vs. NR, P=0.002) durations than their PP- counterparts. Furthermore, the PP+ retained its independent prognostic significance in multivariate analysis (P<0.001).

CONCLUSION

Present results uncovered the pre-C-CRT PP as an independent predictor of poor prognosis for NPC patients, which underscore the requirement for the fortification of the local and systemic treatments in hypoxic NPCs.

Prognostic value and the potential role of treatment options for cervical lymph node necrosis in nasopharyngeal carcinoma

OBJECTIVE

There were few studies focused on the cervical lymph necrosis (CNN) of nasopharyngeal carcinoma (NPC) patients to develop a nomogram and guide the treatment decision at the era of intensity modulated radiation therapy (IMRT).

MATERIAL AND METHODS

The prognostic accuracy of CNN in the training cohort (n = 1940) was validated in Guangzhou internal validation cohort (n = 832) and two external validation cohorts (Dongguan, n = 232; Foshan, n = 134).

RESULTS

The primary end point was progression-free survival (PFS), calculated using the Kaplan-Meier method. After a median 60.0 months' follow-up, patients with CNN in the training cohort had worse 5-year PFS (70.8% vs. 89.1%, P < 0.001) than patients without CNN, which was validated in the validation cohorts. The nomogram based on CNN predicted an individual PFS risk (training: C-index 0.733; Guangzhou validation: C-index 0.736; Foshan: C-index 0.722; Dongguan: C-index 0.756). Stage N2 patients in the CNN group and stage IV patients no matter the status of CNN, PFS was better with induction chemotherapy (ICT) and CCRT than CCRT (P < 0.05).

CONCLUSION

Taken together, CNN reliably predicts survival risk in NPC patients. N2 patients in the CNN group and stage IV patients may receive survival benefit from ICT.

Nodal grouping in nasopharyngeal carcinoma: prognostic significance, N classification, and a marker for the identification of candidates for induction chemotherapy

OBJECTIVES

This study aimed to evaluate the value of nodal grouping (NG), defined as the presence of at least three contiguous lymph nodes (LNs) within one LN region, in staging and management of patients with non-metastatic nasopharyngeal carcinoma (NPC).

METHODS

MR images were reviewed to evaluate LN variables, including NG. The Kaplan-Meier method and multivariate Cox regression models evaluated the association between the variables and survival. Harrell's concordance index (C-index) was used to measure the performance of prognostic models. The outcome of induction chemotherapy (IC) in patients with and without NG was compared using matched-pair analysis.

RESULTS

In 1224 patients enrolled, NG was found to be an independent prognostic factor for overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and regional recurrence-free survival. The hazard ratio and 95% confidence interval (CI) of NG for OS (3.86, 2.09-7.12) were higher than those of stage N2 (3.54, 1.89-6.70). On upgrading patients with NG from stages N1 to N2, the revised N staging yielded a higher C-index compared to the American Joint Committee on Cancer system in predicting PFS (0.664 vs. 0.658, p = 0.022) and DMFS (0.699 vs. 0.690, p = 0.005). Results of the matched-pair analysis revealed that for patients with NG in stages N1 and N2, IC was correlated with improved OS (p = 0.022), PFS (p = 0.007), and DMFS (p = 0.021).

CONCLUSIONS

NG is a significant prognostic factor for patients with NPC. Patients with NG may be upgraded from stages N1 to N2. NG was also a marker for identifying patients who would benefit from IC.

KEY POINTS

• Nodal grouping, defined as the presence of at least three contiguous LNs within one LN region on MRI, was identified as a significant prognostic factor. • In patients with nasopharyngeal carcinoma, nodal grouping may influence lymph node staging. • Nodal grouping was a marker for identifying patients who may benefit from induction chemotherapy.

Prognostic Value and Staging Classification of Lymph Nodal Necrosis in Nasopharyngeal Carcinoma after Intensity-Modulated Radiotherapy

Purpose

The aim of the present study was to evaluate the prognostic value of magnetic resonance imaging (MRI)‒determined lymph nodal necrosis (LNN) in nasopharyngeal carcinoma (NPC) and explore the feasibility of an N-classification system based on the 8th edition of the American Joint Committee on Cancer (AJCC) system.

Materials and Methods

The MRI scans of 616 patients with newly diagnosed stage T1-4N1-3M0 NPC who were treated with definitive intensity-modulated radiotherapy (IMRT) were reviewed.

Results

Multivariate analysis showed that LNN was an independent negative prognostic predictor of distant metastasis free survival (hazard ratio, 1.634; 95% confidence interval, 1.023 to 2.609; p=0.040) and overall survival (hazard ratio, 2.154; 95% confidence interval, 1.282 to 3.620; p=0.004). Patients of classification N1 disease with LNN were reclassified as classification N2, and classification N2 disease with LNN as classification N3 in the proposed N-classification system. Correlation with death and distant failure was significant, and the total difference between N1 and N3 was wider with the proposed system.

Conclusion

MRI-determined LNN is an independent negative prognostic factor for NPC. The proposed N classification system is powerfully predictive.

Combined prognostic value of pretreatment anemia and cervical node necrosis in patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: A large-scale retrospective study

This study investigated the combined prognostic value of pretreatment anemia and cervical node necrosis (CNN) in patients with nasopharyngeal carcinoma (NPC). Retrospective review of 1302 patients with newly diagnosed nonmetastatic NPC treated with intensity-modulated radiotherapy (IMRT) ± chemotherapy. Patients were classified into four groups according to anemia and CNN status. Survival was compared using the log-rank test. Independent prognostic factors were identified using the Cox proportional hazards model. The primary end-point was overall survival (OS); secondary end-points were disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS). Pretreatment anemia was an independent, adverse prognostic factor for DMFS; pretreatment CNN was an independent adverse prognostic factor for all end-points. Five-year survival for non-anemia and non-CNN, anemia, CNN, and anemia and CNN groups were: OS (93.1%, 87.2%, 82.9%, 76.3%, P < 0.001), DFS (87.0%, 84.0%, 73.9%, 64.6%, P < 0.001), DMFS (94.1%, 92.1%, 82.4%, 72.5%, P < 0.001), and LRRFS (92.8%, 92.4%, 88.7%, 84.0%, P = 0.012). The non-anemia and non-CNN group had best survival outcomes; anemia and CNN group, the poorest. Multivariate analysis demonstrated combined anemia and CNN was an independent prognostic factor for OS, DFS, DMFS, and LRRFS (P < 0.05). The combination of anemia and CNN is an independent adverse prognostic factor in patients with NPC treated using IMRT ± chemotherapy. Assessment of pretreatment anemia and CNN improved risk stratification, especially for patients with anemia and CNN who have poorest prognosis. This study may aid the design of individualized treatment plans to improve treatment outcomes.