Prognostic value of MRI-determined cervical lymph node size in nasopharyngeal carcinoma

Radiotherapy alone versus concurrent chemoradiotherapy in patients with stage II and T3N0 nasopharyngeal carcinoma with adverse features: A propensity score-matched cohort study

BACKGROUND AND PURPOSE

Whether concurrent chemoradiotherapy would provide survival benefits in patients with stage II and T3N0 NPC with adverse factors remains unclear in IMRT era. We aimed to assess the value of concurrent chemotherapy compared to IMRT alone in stage II and T3N0 NPC with adverse features.

MATERIALS AND METHODS

287 patients with stage II and T3N0 NPC with adverse factors were retrospectively analyzed, including 98 patients who received IMRT alone (IMRT alone group) and 189 patients who received cisplatin-based concurrent chemotherapy (CCRT group). The possible prognostic factors were balanced using propensity score matching (PSM). Kaplan-Meier analysis was used to evaluate the survival rates, and log-rank tests were employed to compare differences between groups.

RESULTS

The median follow-up duration was 90.8 months (interquartile range = 75.6-114.7 months). The IMRT alone and the CCRT group were well matched; however, for all survival-related endpoints, there were no significant differences between them (5-year failure-free survival: 84.3% vs. 82.7%, P value = 0.68; 5-year overall survival: 87.3% vs. 90.6%, P value = 0.11; 5-year distant metastasis-free survival: 92.8% vs. 92.5%, P value = 0.97; 5-year locoregional relapse-free survival: 93.4% vs. 89.9%, P value = 0.30). The incidence of acute toxicities in the IMRT alone group was significantly lower than that in the CCRT group.

CONCLUSION

For patients with stage II and T3N0 NPC with adverse features treated using IMRT, no improvement in survival was gained by adding concurrent chemotherapy; however, the occurrence of acute toxicities increased significantly. For those combined with non-single adverse factors, the comprehensive treatment strategy needs further exploration.

Diagnostic Performance of Node Reporting and Data System Magnetic Resonance Imaging Score in Detecting Metastatic Cervical Lymph Nodes of Nasopharyngeal Carcinoma

Background

The Node Reporting and Data System (Node-RADS) is a recently proposed classification system for the categorization of lymph nodes in radiological images. This study was conducted to retrospectively evaluate the diagnostic accuracy of the Node-RADS score for metastatic cervical lymph nodes on magnetic resonance imaging (MRI) of patients with nasopharyngeal carcinoma (NPC).

Methods

We retrospectively analyzed cervical lymph nodes of NPC cases. Two radiologists independently evaluated each lymph node on the MRI scans using Node-RADS. Interobserver agreement between 2 radiologists for Node-RADS score assessment was evaluated by linear weighted kappa statistics. The correlation between metastasis and the Node-RADS score of each lymph node was analyzed using multivariate regression analysis. To investigate the diagnostic performance of the Node-RADS score, we further conducted receiver operating characteristic curve analysis. Correspondently, the sensitivity, specificity, positive predictive value, and negative predictive value of each different cutoff (>1, >2, >3, and >4) were computed.

Results

In all, 119 patients with NPC were assessed, including 203 cervical lymph nodes consisting of 140 (69%) of 203 metastatic and 63 (31%) of 203 benign. The kappa agreement between the 2 readers for the Node-RADS score was 0.863 (95% CI = 0.830-0.897, P < .001). Node-RADS score on MRI scan was shown to be an independent predictive factor of lymph node metastasis after multivariate regression analysis (odds ratio [OR] = 6.745, 95% CI = 3.964-11.474, P < .001). Node-RADS achieved an area under the curve (AUC) of 0.950 (95% CI = 0.921-0.979) in diagnosing metastatic lymph nodes. When Node-RADS >2 was identified as the best cutoff based on balanced values, the sensitivity and positive predictive value were 0.92 and 0.94, respectively.

Conclusions

Our study suggests that the Node-RADS score has high accuracy in predicting NPC cervical lymph node metastasis. Nevertheless, this conclusion requires confirmation in a larger cohort of patients with NPC.

Predictive function of tumor burden-incorporated machine-learning algorithms for overall survival and their value in guiding management decisions in patients with locally advanced nasopharyngeal carcinoma

Objective

Accurate prognostic predictions and personalized decision-making on induction chemotherapy (IC) for individuals with locally advanced nasopharyngeal carcinoma (LA-NPC) remain challenging. This research examined the predictive function of tumor burden-incorporated machine-learning algorithms for overall survival (OS) and their value in guiding treatment in patients with LA-NPC.

Methods

Individuals with LA-NPC were reviewed retrospectively. Tumor burden signature-based OS prediction models were established using a nomogram and two machine-learning methods, the interpretable eXtreme Gradient Boosting (XGBoost) risk prediction model, and DeepHit time-to-event neural network. The models' prediction performances were compared using the concordance index (C-index) and the area under the curve (AUC). The patients were divided into two cohorts based on the risk predictions of the most successful model. The efficacy of IC combined with concurrent chemoradiotherapy was compared to that of chemoradiotherapy alone.

Results

The 1 221 eligible individuals, assigned to the training (n = 813) or validation (n = 408) set, showed significant respective differences in the C-indices of the XGBoost, DeepHit, and nomogram models (0.849 and 0.768, 0.811 and 0.767, 0.730 and 0.705). The training and validation sets had larger AUCs in the XGBoost and DeepHit models than the nomogram model in predicting OS (0.881 and 0.760, 0.845 and 0.776, and 0.764 and 0.729, P < 0.001). IC presented survival benefits in the XGBoost-derived high-risk but not low-risk group.

Conclusion

This research used machine-learning algorithms to create and verify a comprehensive model integrating tumor burden with clinical variables to predict OS and determine which patients will most likely gain from IC. This model could be valuable for delivering patient counseling and conducting clinical evaluations.

Two web-based dynamically interactive nomograms and risk stratification systems for predicting survival outcomes and guiding treatment in non-metastatic nasopharyngeal carcinoma

BACKGROUND

A nomogram is a valuable and easily accessible tool for individualizing cancer prognosis. This study aims to establish and validate two prognostic nomograms for long-term overall survival (OS) and cancer-specific survival (CSS) in non-metastatic nasopharyngeal carcinoma (NPC) patients and to investigate the treatment options for the nomogram-based risk stratification subgroups.

METHODS

A total of 3959 patients with non-metastatic NPC between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The patients were randomly allocated to the training and validation cohorts in a 7:3 ratio. Prognostic nomograms were constructed to estimate OS and CSS by integrating significant variables from multivariate Cox regression employing a backward stepwise method. We examined the correlation indices (C-index) and areas under the curves (AUC) of time-dependent receiver operating characteristic curves to assess the discriminative ability of our survival models. The comprehensive enhancements of predictive performance were evaluated with net reclassification operating improvement (NRI) and integrated discrimination improvement (IDI). Reliability was validated using calibration plots. Decision curve analysis (DCA) was used to estimate clinical efficacy and capability. Finally, the nomogram-based risk stratification system used Kaplan-Meier survival analysis and log-rank tests to examine differences between subgroups.

RESULTS

The following independent parameters were significant predictors for OS: sex, age, race, marital status, histological type, median household income, AJCC stage tumor size, and lymph node size. Except for the race variables mentioned above, the rest were independent prognostic factors for CSS. The C-index, AUC, NRI, and IDI indicated satisfactory discriminating properties. The calibration curves exhibited high concordance with the exact outcomes. Moreover, the DCA demonstrated performed well for net benefits. The prognosis significantly differed between low- and high-risk patients (p < 0.001). In a treatment-based stratified survival analysis in risk-stratified subgroups, chemotherapy benefited patients in the high-risk group compared to radiotherapy alone. Radiotherapy only was recommended in the low-risk group.

CONCLUSIONS

Our nomograms have satisfactory performance and have been validated. It can assist clinicians in prognosis assessment and individualized treatment of non-metastatic NPC patients.

Development of A Nomogram for Progression-free Survival in Patients with Stage II/T3N0 Nasopharyngeal Carcinoma to Explore Different Treatment Modalities

Purpose To explore the prognostic value of clinical and serological risk factors for progression-free survival (PFS) in stage II and T3N0 nasopharyngeal carcinoma (NPC) and construct a nomogram based on these factors. Additionally, to investigate the long-term survival and short-term toxic reactions of patients in different risk stratification under different treatment modalities. Methods The patients were randomly divided into training and validation cohorts in a 7:3 ratio. Independent prognostic factors were identified using Cox regression analysis, and a nomogram was constructed by combining these predictive factors with the TNM staging system. The nomogram was then validated in the validation cohort, and patients were classified into different risk groups based on the nomogram. The PFS, overall survival (OS), and acute toxicities were compared among different treatment modalities after balancing baseline characteristics. Results Multivariate Cox regression analysis indicated that pathological type, alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were independent prognostic factors(p<0.05) in this study. The nomogram showed good prognostic accuracy in both the training and validation cohorts (C-index of 0.73 and 0.70, respectively). In the different risk subgroups, there were no statistically significant differences in PFS and OS between radiotherapy and chemoradiotherapy groups(p>0.05). The treatment modality of combined chemotherapy was associated with more acute toxic reactions. Conclusion We established and validated a nomogram for predicting PFS in patients with stage II/T3N0 NPC. Intensity-modulated radiation therapy (IMRT) combined with chemotherapy did not provide additional survival benefits for these patients and was associated with more chemotherapy-related side effects.

Involved site radiation therapy in stage I-III nasopharyngeal carcinoma with limited lymph node burden (ISRT-NPC) or elective region irradiation: a study protocol for a multicenter non-inferiority randomized controlled phase III clinical trial

BACKGROUND

Current radiotherapy guidelines and consensus statements uniformly recommend elective region irradiation (ERI) as the standard strategy for nasopharyngeal carcinoma (NPC). However, given the scarcity of skip-metastasis, the improved assessment accuracy of nodal involvement, and the striking advancements in chemotherapy for NPC, a one-fits-all delineation scheme for clinical target volumes of the nodal region (CTVn) may not be appropriate anymore, and modifications of the CTVn delineation strategy may be warranted. Involved site irradiation (ISI) covering merely the initially involved nodal site and potential extranodal extension has been confirmed to be as effective as ERI with decreased radiation-related toxicities in some malignancies, but has not yet been investigated in NPC. This study aims to compare the regional control, survival outcomes, radiation-related toxicities, and quality of life (QoL) of ISI with conventional ERI in NPC patients with a limited nodal burden.

METHODS

ISRT-NPC is a prospective, multicenter, open-label, noninferiority, phase III randomized controlled trial. A total of 414 patients will be randomly assigned in a 1:1 ratio to receive ISI or ERI. Randomization will be stratified by institution scale and N stage. Generally, in the ISI group, the high-risk CTV1 (dose: 60 Gy) includes a 1-cm expansion of the positive LN as well as the VIIa and the retrostyloid space above the bilateral transverse process of the atlantoaxial spine (C1), regardless of N status. The low-risk CTV2 (dose: 50 Gy) covers the cervical nodal region with a 3-cm caudal expansion below the transverse process of C1 for N0 disease and a 3-cm expansion below the positive LN for positive LNs.

DISCUSSION

The results of this trial are expected to confirm that ISI is a non-inferior strategy to ERI in stage I-III patients with low LN burden, enabling the minimization of treatment-related toxicity and improvement of long-term QoL without compromising regional control.

TRIAL REGISTRATION

ClinicalTrails.gov, NCT05145660. Registered December 6, 2021.

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.

A prognostic nomogram incorporating tumor size and lymph node size for patients with nasopharyngeal carcinoma

PURPOSE

The goal of this study was to establish a nomogram that included pre-treatment tumor size and lymph node (LN) size to assess personalized overall survival (OS) of patients with nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

The Surveillance, Epidemiology, and End Results dataset was used to extract statistics for 1083 individuals with NPC (training cohort). In the validation cohort, 266 patients were included from the Affiliated Cancer Hospital & Institute of Guangzhou Medical University. Age, tumor-node-metastasis (TNM) stage, pre-treatment tumor size, and LN size were chosen in both the training and validation sets to build a nomogram to forecast the 3-year and 5-year OS probability using the multivariate Cox regression model. Using the C-index, calibration plot, and receiver operating characteristic (ROC) curve, the predictive model's predictive value and discriminative capacity were determined.

RESULTS

Pre-treatment tumor size, LN size, age, and TNM stage were all independent prognostic factors in the multivariate analysis. After combining these characteristics, a nomogram with a C-index of 0.7367 in the training cohort and 0.795 in the validation cohort was created, suggesting strong predictive capacity. Analysis of the ROC curve revealed that the constructed nomogram was clinically applicable.

CONCLUSIONS

In patients with NPC, the developed nomogram, which includes pre-treatment tumor size, LN size, age, and TNM stage, is a reliable predictive predictor of OS.

Using ultrasound radiomics analysis to diagnose cervical lymph node metastasis in patients with nasopharyngeal carcinoma

OBJECTIVE

This study aimed to explore the clinical value of ultrasound radiomics analysis in the diagnosis of cervical lymph node metastasis (CLNM) in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 205 cases of NPC CLNM and 284 cases of benign lymphadenopathy with pathologic diagnosis were retrospectively included. Grayscale ultrasound (US) images of the largest section of every lymph node underwent feature extraction. Feature selection was done by maximum relevance minimum redundancy (mRMR) algorithm and multivariate logistic least absolute shrinkage and selection operator (LASSO) regression. Logistic regression models were developed based on clinical features, radiomics features, and the combination of those features. The AUCs of models were analyzed by DeLong's test.

RESULTS

In the clinical model, lymph nodes in the upper neck, larger long axis, and unclear hilus were significant factors for CLNM (p < 0.001). MRMR and LASSO regression selected 7 significant features for the radiomics model from the 386 radiomics features extracted. In the validation dataset, the AUC value was 0.838 (0.776-0.901) in the clinical model, 0.810 (0.739-0.881) in the radiomics model, and 0.880 (0.826-0.933) in the combined model. There was not a significant difference between the AUCs of clinical models and radiomics models in both datasets. DeLong's test revealed a significantly larger AUC in the combined model than in the clinical model in both training (p = 0.049) and validation datasets (p = 0.027).

CONCLUSION

Ultrasound radiomics analysis has potential value in screening meaningful ultrasound features and improving the diagnostic efficiency of ultrasound in CLNM of patients with NPC.

KEY POINTS

• Radiomics analysis of gray-scale ultrasound images can be used to develop an effective radiomics model for the diagnosis of cervical lymph node metastasis in nasopharyngeal carcinoma patients. • Radiomics model combined with general ultrasound features performed better than the clinical model in differentiating cervical lymph node metastases from benign lymphadenopathy.

Caudal distribution pattern of metastatic neck lymph nodes in nasopharyngeal carcinoma and prognostic significance of nodal spread distances

OBJECTIVE

To investigate the caudal distribution pattern of metastatic neck lymph nodes (LNs) in nasopharyngeal carcinoma (NPC) and the prognostic significance of nodal spread distances (SDs).

MATERIALS AND METHODS

NPC patients with neck metastatic LNs were enrolled. The most caudally located LNs were marked. SD was defined as the distance from marked LNs to the lateral process of the atlantoaxial spine (LPC1). Univariate and multivariate analyses were performed to assess association between MRI-identified nodal features and survival. Harrell's concordance index (C-index) and area under the curve (AUC) were used to compare AJCC (8th edition) N staging with the proposed N staging. Survival after induction chemotherapy plus concurrent chemoradiotherapy (IC + CCRT) versus CCRT alone was compared between different SD groups.

RESULTS

A total of 1907 LNs (1164 patients) were contoured. SD > 7 cm was an independent predictor of overall survival (OS), distant metastasis-free survival (DMFS), and progression-free survival (PFS), with hazard ratios of 1.725, 1.553 and 1.414, respectively. When patients with SD > 7 cm were upgraded one N stage higher, the proposed N classification showed better stratification in OS, DMFS, and PFS between N1 and N2 stages. C-indices and AUCs of the proposed N staging were superior to AJCC N staging. IC + CCRT showed negative effect in N1-2 patients with SD ≤ 7 cm but improved OS in those with SD > 7 cm.

CONCLUSION

SD of metastatic LNs can predict survival in NPC. Integration of SD into AJCC N staging could improve its prognostic value and help identify patients requiring IC.

MRI-identified multidimensional nodal features predict survival and concurrent chemotherapy benefit for stage II nasopharyngeal carcinoma

BACKGROUND

Reliable predictors are urgently needed to identify stage II nasopharyngeal carcinoma (NPC) patients who could benefit from concurrent chemoradiotherapy (CCRT). We aimed to develop a nomogram integrating MRI-identified multidimensional features of lymph nodes to predict survival and assist the decision-making of CCRT for stage II NPC.

PATIENTS AND METHODS

This retrospective study enrolled 242 stage II NPC patients treated from January 2007 to December 2017. Overall survival (OS) was the primary endpoint. Performance of nomogram was evaluated using calibration curves, Harrell Concordance Index (C-index), area under the curve (AUC) and decision curves analysis (DCA) and was compared with TNM staging. According to the individualized nomogram score, patients were classified into two risk cohorts and therapeutic efficacy of CCRT were evaluated in each cohort.

RESULTS

Three independent prognostic factors for OS: age, number and location of positive lymph nodes were included into the final nomogram. T stage was also incorporated due to its importance in clinical decision-making. Calibration plots demonstrated a good match between the predicted and our observed OS rates. C-index for nomogram was 0.726 compared with 0.537 for TNM staging (p < 0.001). DCAs confirmed the superior clinical utility of nomograms compared with TNM staging. CCRT compared to intensity-modulated radiotherapy (IMRT) delivered OS benefit to patients in the high-risk group (5-year: 89.9% vs. 72.1%; 10-year: 72.5% vs. 34.2%, p = 0.011), but not in the low-risk group.

CONCLUSIONS

This lymph node features-based nomogram demonstrated excellent discrimination and predictive accuracy for stage II patients and could identify patients who can benefit from CCRT.

Prognostic value of MRI-determined cervical lymph node size in nasopharyngeal carcinoma

Objectives

To investigate the prognostic value of magnetic resonance imaging (MRI)‐determined cervical lymph node (CLN) size in nasopharyngeal carcinoma (NPC).

Methods

We retrospectively reviewed 2066 patients with NPC treated with intensity‐modulated radiotherapy, and randomly divided them into two groups, in a 1:1 ratio. One group was used for training (the training group), and the other one was for internal validation (the validation group). All patients had undergone MRI examination and the maximal axial diameters (MAD) of the axial plane of all positive nodes had been measured and recorded.

Results

Of 683 patients with CLN metastases in the training group (n = 1033), MAD = 4 cm was associated with worse OS (64.7% vs 84.6%, P < .001), DFS (55.9% vs 76.3%, P = .001), and DMFS (67.6% vs 86.1%, P = .001). Multivariate analysis showed that MAD = 4 cm was a significant negative prognostic factor for OS (HR = 2.058; P = .025), DFS (HR = 1.727; P = .049), and DMFS (HR = 2.034; P = .036). When MRI‐determined MAD = 4 cm was classified as N3 in the N classification, the OS, DFS, DMFS, and RRFS survival curves were well separated. The OS, DFS, DMFS, and RRFS concordance indexes were not statistically different between the proposed N staging system and the UICC/AJCC staging system in the training group, or between the training group and the validation group (all P = .05).

Conclusion

MAD = 4 cm on axial MRI slices can be recommended as a prognostic factor in future versions of the UICC/AJCC NPC staging system.