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

Use of survival support vector machine combined with random survival forest to predict the survival of nasopharyngeal carcinoma patients

Background

The Cox regression model is not sufficiently accurate to predict the survival prognosis of nasopharyngeal carcinoma (NPC) patients. It is impossible to calculate and rank the importance of impact factors due to the low predictive accuracy of the Cox regression model. So, we developed a system. Using the SEER (The Surveillance, Epidemiology, and End Results) database data on NPC patients, we proposed the use of random survival forest (RSF) and survival-support vector machine (SVM) from the machine learning methods to develop a survival prediction system specifically for NPC patients. This approach aimed to make up for the insufficiency of the Cox regression model. We also used the Cox regression model to validate the development of the nomogram and compared it with machine learning methods.

Methods

A total of 1,683 NPC patients were extracted from the SEER database from January 2010 to December 2015. We used R language for modeling work, established the nomogram of survival prognosis of NPC patients by Cox regression model, ranked the correlation of influencing factors by RSF model VIMP (variable important) method, developed a survival prognosis system for NPC patients based on survival-SVM, and used C-index for model evaluation and performance comparison.

Results

Although the Cox regression models can be developed to predict the prognosis of NPC patients, their accuracy was lower than that of machine learning methods. When we substituted the data for the Cox model, the C-index for the training set was only 0.740, and the C-index for the test set was 0.721. In contrast, the C index of the survival-SVM model was 0.785. The C-index of the RSF model was 0.729. The importance ranking of each variable could be obtained according to the VIMP method.

Conclusions

The prediction results from the Cox model are not as good as those of the RSF method and survival-SVM based on the machine learning method. For the survival prognosis of NPC patients, the machine learning method can be considered for clinical application.

Multi-task deep learning-based radiomic nomogram for prognostic prediction in locoregionally advanced nasopharyngeal carcinoma

PURPOSE

Prognostic prediction is crucial to guide individual treatment for locoregionally advanced nasopharyngeal carcinoma (LA-NPC) patients. Recently, multi-task deep learning was explored for joint prognostic prediction and tumor segmentation in various cancers, resulting in promising performance. This study aims to evaluate the clinical value of multi-task deep learning for prognostic prediction in LA-NPC patients.

METHODS

A total of 886 LA-NPC patients acquired from two medical centers were enrolled including clinical data, [18F]FDG PET/CT images, and follow-up of progression-free survival (PFS). We adopted a deep multi-task survival model (DeepMTS) to jointly perform prognostic prediction (DeepMTS-Score) and tumor segmentation from FDG-PET/CT images. The DeepMTS-derived segmentation masks were leveraged to extract handcrafted radiomics features, which were also used for prognostic prediction (AutoRadio-Score). Finally, we developed a multi-task deep learning-based radiomic (MTDLR) nomogram by integrating DeepMTS-Score, AutoRadio-Score, and clinical data. Harrell's concordance indices (C-index) and time-independent receiver operating characteristic (ROC) analysis were used to evaluate the discriminative ability of the proposed MTDLR nomogram. For patient stratification, the PFS rates of high- and low-risk patients were calculated using Kaplan-Meier method and compared with the observed PFS probability.

RESULTS

Our MTDLR nomogram achieved C-index of 0.818 (95% confidence interval (CI): 0.785-0.851), 0.752 (95% CI: 0.638-0.865), and 0.717 (95% CI: 0.641-0.793) and area under curve (AUC) of 0.859 (95% CI: 0.822-0.895), 0.769 (95% CI: 0.642-0.896), and 0.730 (95% CI: 0.634-0.826) in the training, internal validation, and external validation cohorts, which showed a statistically significant improvement over conventional radiomic nomograms. Our nomogram also divided patients into significantly different high- and low-risk groups.

CONCLUSION

Our study demonstrated that MTDLR nomogram can perform reliable and accurate prognostic prediction in LA-NPC patients, and also enabled better patient stratification, which could facilitate personalized treatment planning.

An overall survival predictive nomogram to identify high-risk patients among locoregionally advanced nasopharyngeal carcinoma: Developed based on the SEER database and validated institutionally

Objective

Locoregionally advanced nasopharyngeal carcinoma (LA-NPC) patients, even at the same stage, have different prognoses. We aim to construct a prognostic nomogram for predicting the overall survival (OS) to identify the high-risk LA-NPC patients.

Materials and methods

Histologically diagnosed WHO type II and type III LA-NPC patients in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled as the training cohort (n= 421), and LA-NPC patients from Shantou University Medical College Cancer Hospital (SUMCCH) served as the external validation cohort (n= 763). Variables were determined in the training cohort through Cox regression to form a prognostic OS nomogram, which was verified in the validation cohort, and compared with traditional clinical staging using the concordance index (C-index), Kaplan–Meier curves, calibration curves and decision curve analysis (DCA). Patients with scores higher than the specific cut-off value determined by the nomogram were defined as high-risk patients. Subgroup analyses and high-risk group determinants were explored.

Results

Our nomogram had a higher C-index than the traditional clinical staging method (0.67 vs. 0.60, p<0.001). Good agreement between the nomogram-predicted and actual survival were shown in the calibration curves and DCA, indicating a clinical benefit of the nomogram. High-risk patients identified by our nomogram had worse prognosis than the other groups, with a 5-year overall survival (OS) of 60.4%. Elderly patients at advanced stage and without chemotherapy had a tendency for high risk than the other patients.

Conclusions

Our OS predictive nomogram for LA-NPC patients is reliable to identify high-risk patients.

Treatment of Recurrent Nasopharyngeal Carcinoma: A Sequential Challenge

Simple Summary

Recurrent nasopharyngeal carcinoma is one of the major causes of death among NPC patients. However, there are no international guidelines for the treatment of patients with recurrent NPC now. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC.

Abstract

Recurrent nasopharyngeal carcinoma (NPC), which occurs in 10–20% of patients with primary NPC after the initial treatment modality of intensity-modulated radiation therapy (IMRT), is one of the major causes of death among NPC patients. Patients with recurrent disease without distant metastases still have a chance to be saved, but re-treatment often carries more serious toxicities or higher risks. For this group of patients, both otolaryngologists and oncologists are committed to developing more appropriate treatment regimens that can prolong patient survival and improve survival therapy. Currently, there are no international guidelines for the treatment of patients with recurrent NPC. In this article, we summarize past publications on clinical research and mechanistic studies related to recurrent NPC, combined with the experience and lessons learned by our institutional multidisciplinary team in the treatment of recurrent NPC. We propose an objective protocol for the treatment of recurrent NPC.

External Validation of a Nomogram and Risk Grouping System for Predicting Individual Prognosis of Patients With Medulloblastoma

Background: Medulloblastoma (MB) is one of the most malignant neuroepithelial tumors in the central nervous system. This study aimed to establish an effective prognostic nomogram and risk grouping system for predicting overall survival (OS) of patients with MB.

Materials and Methods: The nomogram was constructed based on data from the database of Surveillance, Epidemiology, and End Results (SEER). This database consisted of 2,824 patients with medulloblastoma and was used as the training cohort. The data of another additional 161 patients treated at the Sun Yat-sen University Cancer Center (SYSUCC) were used as the external validation cohort. Cox regression analysis was used to select independent prognostic factors. Concordance index (C-index) and calibration curve were used to predict the prognostic effect of the nomogram for overall survival.

Results: In the training cohort, Cox regression analyses showed that the prognostic factors included histopathology, surgery, radiotherapy, chemotherapy, tumor size, dissemination, and age at diagnosis. The internal and external validated C-indexes were 0.681 and 0.644, respectively. Calibration curves showed that the nomogram was able to predict 1-, 3-, and 5-year OS for patients with MB precisely. Using the training cohort, a risk grouping system was built, which could perfectly classify patients into four risk nomogroups with a 5-year survival rate of 83.9%, 76.5%, 64.5%, and 46.8%, respectively.

Conclusion: We built and validated a nomogram and risk grouping system that can provide individual prediction of OS and distinguish MB patients from different risk groups. This nomogram and risk grouping system could help clinicians making better treatment plan and prognostic assessment.

Clinicopathological and prognostic features of nasopharyngeal carcinoma in children and adolescents: A retrospective study of 196 cases in South China

Nasopharyngeal carcinoma (NPC) occurring in children and adolescence is extremely rare and till present there is a lack of understanding on their clinicopathological and prognostic features of this rare entity. For our study, data of 196 cases children and adolescents with NPC from the past 18 years at a high-volume cancer center from South China were retrospectively analyzed. Half of the evaluated NPC patients (83/166, 50.0%) were staged as Stage IVa disease, whereas 1.2% (2/166), 27.7% (46/166), 16.9% (28/166) and 4.2% (7/166) had Stage II, III, IVb and IVc disease, respectively. Serum EBV EA-IgA ≥1:10 and VCA-IgA ≥1:40 were found in 67.7% (113/167) and 76.6% (128/167) of the evaluated patients, respectively, whereas 56.8% (84/148) of the patients had plasma EBV DNA ≥1000 copies/mL. Histologically, all tumors were classified as nonkeratinizing squamous cell carcinoma (NK-SCC). Immunohistochemistrically, the expression of CK (AE1/AE3), P63, CK5/6 and P40 were observed in 100% (88/88), 93.2% (68/73), 84.1% (58/69) and 63.2% (12/19) of the detected cases, respectively. All cases show similar immunophenotype compared to that occurring in adult patients. All evaluated cases (71/71 100%) harbored EBER. Patients with plasma EBV DNA ≥1000 copies/mL and positive serum EBV antibodies had significantly inferior 3-year OS (88% vs 100%, P = .007) compared to other corresponding groups. The combination of EBV serology and plasma EBV DNA are useful to predict the outcome of patients with NPC in children and adolescents.

Risk stratification for nasopharyngeal carcinoma: a real-world study based on locoregional extension patterns and Epstein-Barr virus DNA load

Aim:

The present study aimed to evaluate the combined value of locoregional extension patterns (LEPs) and circulating cell-free Epstein–Barr virus (cf EBV) DNA for risk stratification of locoregionally advanced nasopharyngeal carcinoma (LA-NPC) to better guide therapeutic strategies.

Methods:

A total of 7227 cases of LA-NPC were reviewed retrospectively and classified into six groups according to their LEP (ascending, descending, or mixed type) and pre-treatment cf EBV-DNA load (⩾ versus <4000 copy/ml). Using a supervised statistical clustering approach, patients in the six groups were clustered into low, intermediate, and high-risk clusters. Progression-free survival (PFS), overall survival (OS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS) were calculated using the Kaplan–Meier method and differences were compared using the log-rank test.

Results:

Survival curves for the low, intermediate, and high-risk clusters were significantly different for all endpoints. The 5-year survival rate for the low, intermediate, and high-risk clusters, respectively, were: PFS (83.5%, 73.2%, 62.6%, p < 0.001), OS (91.0%, 82.7%, 73.2%, p < 0.001), DMFS (92.3%, 83.0%, 73.4%, p < 0.001), and LRRFS (91.0%, 88.0%, 83.3%, p < 0.001). The risk clusters acted as independent prognostic factors for all endpoints. Among the patients in the high-risk cluster, neoadjuvant chemotherapy combined with concurrent chemoradiotherapy (CCRT) significantly improved the patients 5-year PFS (66.4% versus 57.9%, p = 0.014), OS (77.6% versus 68.6%; p < 0.002), and DMFS (76.6% versus 70.6%; p = 0.028) compared with those treated with CCRT.

Conclusion:

Our results could facilitate the development of risk-stratification and risk-adapted therapeutic strategies for patients with LA-NPC.

The role of capecitabine as maintenance therapy in de novo metastatic nasopharyngeal carcinoma: A propensity score matching study

Background

Capecitabine was previously used as a second‐line or salvage therapy for metastatic nasopharyngeal carcinoma (NPC) and has shown satisfactory curative effect as maintenance therapy in other metastatic cancers. This study aimed to explore the role of capecitabine as maintenance therapy in de novo metastatic NPC patients with different plasma Epstein‐Barr virus (EBV) DNA levels before treatment.

Methods

We selected de novo metastatic NPC patients treated with locoregional radiotherapy (LRRT) for this retrospective study. The propensity score matching (PSM) was applied to balance potential confounders between patients who underwent capecitabine maintenance therapy and those who did not with a ratio of 1:3. Overall survival (OS) was the primary endpoint. The association between capecitabine maintenance therapy and survival was assessed using the log‐rank test and a Cox proportional hazard model.

Results

Among all patients eligible for this study, 64 received capecitabine maintenance therapy after LRRT. After PSM, 192 patients were identified in the non‐maintenance group. In the matched cohort, patients treated with capecitabine achieved a higher 3‐year OS rate compared with patients in the non‐maintenance group (68.5% vs. 61.8%, P = 0.037). Multivariate analysis demonstrated that capecitabine maintenance therapy was an independent prognostic factor. In subgroup analysis, 3‐year OS rate was comparable between the maintenance and non‐maintenance groups in patients with high pretreatment EBV DNA levels (˃30,000 copies/mL) (54.8% vs. 45.8%, P = 0.835), whereas patients with low pretreatment EBV DNA levels (≤30,000 copies/mL) could benefit from capecitabine maintenance therapy in OS (90.0% vs. 68.1%, P = 0.003).

Conclusion

Capecitabine maintenance therapy may be superior to non‐maintenance therapy in prolonging OS for de novo metastatic NPC patients with pretreatment EBV DNA ≤ 30,000 copies/mL.

Lymph Node Status and Outcomes for Nasopharyngeal Carcinoma According to Histological Subtypes: A SEER Population-Based Retrospective Analysis

INTRODUCTION

We aimed to investigate the clinical effect of histological subtypes on survival in nasopharyngeal carcinoma (NPC), and assess the effect of nodal stage on outcome according to histological subtypes.

METHODS

Patients with non-metastatic NPC were identified from the Surveillance, Epidemiology and End-Results (SEER) database between 2004 and 2014. Statistical analysis was performed using the chi-squared test, Kaplan-Meier methods, and multivariate Cox regression models.

RESULTS

We identified 2845 patients in this study including 1218 (42.8%), 849 (29.8%), and 778 (27.3%) patients with keratinizing squamous cell carcinoma (KSCC), differentiated non-keratinizing squamous cell carcinoma (DNKSCC), and undifferentiated non-keratinizing squamous cell carcinoma (UNKSCC), respectively. The multivariate analysis indicated that patients with UNKSCC subtype had better NPC-specific survival (NPC-SS) (P < 0.001) compared to KSCC (P < 0.001) and DNKSCC (P < 0.001) patients. The 5-year NPC-SS was 75.2%, 77.9%, and 88.9% in patients with KSCC, DNKSCC, UNKSCC, respectively (P < 0.001). Subgroup analysis showed that advanced nodal stage was related to lower NPC-SS in patients with DNKSCC and UNKSCC but not in patients with KSCC.

CONCLUSIONS

Histology is an independent prognostic factor in patients with NPC. However, advanced nodal stage is not associated with lower survival in KSCC.

Incidence trends and survival prediction of hepatoblastoma in children: a population-based study

Background

Hepatoblastoma is a rare disease that nevertheless accounts for the majority of liver malignancies in children. Due to limited epidemiological data, therapy for hepatoblastoma tends to be individualized. This study aimed to evaluate incidence trends of hepatoblastoma and to develop a nomogram to predict the survival of children with newly diagnosed hepatoblastoma on a population-based level.

Methods

Individuals up to 18 years of age with hepatoblastoma recorded in 18 registries of the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015 were examined. Joinpoint regression analyses were applied to assess incidence trends in annual percentage change (APC). Multivariable Cox regression was used to identify factors associated with overall survival (OS). A nomogram was constructed to predict OS in individual cases based on independent predictors. Concordance index (C-index) and calibration curves were used to evaluate predictive performance.

Results

Between 2004 and 2015, hepatoblastoma incidence increased significantly (APC, 2.2%; 95% confidence interval [CI] 0.5% to 3.8%, P < 0.05). In particular, this increase was observed among 2- to 4-year-old patients, males, and African–Americans. The 5- and 10-year OS rates were 81.5% and 81.0%, respectively. Age of 2 to 4 years, African–American ethnicity, and no surgery were independent predictors for short OS. Distant disease at presentation was found not to be an independent factor of survival. The nomogram had a C-index of 0.79 (95% CI 0.74–0.84) with appropriate calibration curve fitting.

Conclusions

We constructed a nomogram that integrates common factors associated with survival for hepatoblastoma patients. It provides accurate prognostic prediction for children with hepatoblastoma.

Comparison of radiomics tools for image analyses and clinical prediction in nasopharyngeal carcinoma

Objective:

Radiomics pipelines have been developed to extract novel information from radiological images, which may help in phenotypic profiling of tumours that would correlate to prognosis. Here, we compared two publicly available pipelines for radiomics analyses on head and neck CT and MRI in nasopharynx cancer (NPC).

Methods and materials:

100 biopsy-proven NPC cases stratified by T- and N-categories were enrolled in this study. Two radiomics pipeline, Moddicom (v. 0.51) and Pyradiomics (v. 2.1.2) were used to extract radiomics features of CT and MRI. Segmentation of primary gross tumour volume was performed using Velocity v. 4.0 by consensus agreement between three radiation oncologists. Intraclass correlation between common features of the two pipelines was analysed by Spearman’s rank correlation. Unsupervised hierarchical clustering was used to determine association between radiomics features and clinical parameters.

Results:

We observed a high proportion of correlated features in the CT data set, but not for MRI; 76.1% (51 of 67 common between Moddicom and Pyradiomics) of CT features and 28.6% (20 of 70 common) of MRI features were significantly correlated. Of these, 100% were shape-related for both CT and MRI, 100 and 23.5% were first-order-related, 61.9 and 19.0% were texture-related, respectively. This interpipeline heterogeneity affected the downstream clustering with known prognostic clinical parameters of cTN-status and GTVp. Nonetheless, shape features were the most reproducible predictors of clinical parameters among the different radiomics modules.

Conclusion:

Here, we highlighted significant heterogeneity between two publicly available radiomics pipelines that could affect the downstream association with prognostic clinical factors in NPC

Advances in knowledge:

The present study emphasized the broader importance of selecting stable radiomics features for disease phenotyping, and it is necessary prior to any investigation of multicentre imaging datasets to validate the stability of CT-related radiomics features for clinical prognostication.

Effects of KIF2A on the prognosis of nasopharyngeal carcinoma and nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma (NPC) is a common tumor in south China. Kinesin family member 2A (KIF2A) belongs to the kinesin-13 family and is associated with the growth and invasion of a number of different types of human cancer, including ovarian, breast and prostate cancer. The aim of the present study was to evaluate the expression of KIF2A in NPC and explore the relationship between KIF2A and the basic characteristics of 5-8F cells. Immunohistochemistry was performed on tissues from 97 patients with NPC to assess KIF2A protein expression. KIF2A was knocked down by a specific short interfering (si)RNA in 5-8F cell lines. Cell proliferation, apoptosis and cycle were analyzed by MTT assay and flow cytometry. The invasive ability and angiogenesis were evaluated by Matrigel assay and reverse transcription-quantitative PCR. The level of KIF2A was associated with the growth and migration of primary tumor, nodal status and tumor stage. The viability of KIF2A-knockdown cells was decreased compared with that of the control cells. The number of apoptotic cells, as well as the percentage of cells in the G0/G1 phase, was higher in the KIF2A siRNA group compared with the control group. The invasive and angiogenetic ability of 5-8F cells in the KIF2A siRNA group was decreased compared with the control group. In conclusion, the expression of KIF2A correlated with the poor clinicopathological features in NPC. Therefore, KIF2A may serve an important role in the progression of NPC and proliferation of 5-8F cells, which might present a potential therapeutic target for patients with NPC.

Design of a microfluidic chip consisting of micropillars and its use for the enrichment of nasopharyngeal cancer cells

The aim of the present study was to discuss the design of a microfluidic chip consisting of columns, and its use for the enrichment of nasopharyngeal cancer (NPC) cells. A microfluidic chip experiment was simulated using FLUENT software. Within the microfluidic chip, aptamers were bound to the reaction chamber (consisting of columns) using a biotin-avidin system. Cell suspension was introduced into the reaction chamber to capture NPC cells. NPC cells were subsequently eluted, and the capture rate of the cells was calculated. The modified aptamer-bound microfluidic chip was able to capture NPC cells with a capture rate of ~90%. The modified aptamer-bound microfluidic chip has a wide range of potential applications for the diagnosis of NPC.