Development and External Validation of Nomograms for Predicting Survival in Nasopharyngeal Carcinoma Patients after Definitive Radiotherapy

Abstract

The distant metastasis free survival (DMFS) and overall survival (OS) differ significantly among individuals even within the same clinical stages. The purpose of this retrospective study was to build nomograms incorporating plasma EBV DNA for predicting DMFS and OS of nasopharyngeal carcinoma (NPC) patients after definitive radiotherapy. A total of 1168 non-metastatic NPC patients from two institutions were included to develop the nomograms. Seven and six independent prognostic factors were identified to build the nomograms for OS and DMFS, respectively. The models were externally validated by a separate cohort of 756 NPC patients from the third institutions. For predicting OS, the c-index of the nomogram was significantly better than that of the TNM staging system (Training cohort, P = 0.005; validation cohort, P = 0.03). The c-index of nomogram for DMFS in the training and validation set were both higher than that of TNM classification with marginal significance (P = 0.048 and P = 0.057, respectively). The probability of 1-, 3-, and 5-year OS and DMFS showed optimal agreement between nomogram prediction and actual observation. The proposed stratification of risk groups based on the nomograms allowed significant distinction between Kaplan-Meier curves for survival outcomes. The prognostic nomograms could better stratify patients into different risk groups.

Prognostic nomogram for refining the prognostication of the proposed 8th edition of the AJCC/UICC staging system for nasopharyngeal cancer in the era of intensity‐modulated radiotherapy

“…[25][26][27][28][29][30] These findings underline the inadequacy of the current staging system and the Six studies of the development of nomograms for NPC have been reported in recent years. 5,[31][32][33][34][35] They have demonstrated the feasibility of using a nomogram to predict survival for patients with NPC and have consistently shown superiority over the conventional TNM staging system. However, despite the stronger predictive power of these nomograms, they suffer from important limitations, including obsolete RT techniques [33][34][35] and a lack of external validation, 31,33 that hamper their generalizability and validity in the modern era.…”

“…5,[31][32][33][34][35] They have demonstrated the feasibility of using a nomogram to predict survival for patients with NPC and have consistently shown superiority over the conventional TNM staging system. However, despite the stronger predictive power of these nomograms, they suffer from important limitations, including obsolete RT techniques [33][34][35] and a lack of external validation, 31,33 that hamper their generalizability and validity in the modern era. Furthermore, all are based on the 6th and 7th editions of the AJCC/UICC staging system.…”

“…Furthermore, all are based on the 6th and 7th editions of the AJCC/UICC staging system. 5,[31][32][33][34][35] With the imminent introduction of the 8th edition, the applicability of these nomograms will become outdated.…”

Revalidation of a prognostic score model based on complete blood count for nasopharyngeal carcinoma through a prospective study

“…Besides our model, there were also many approaches made to building prognostic systems based on functional indexes for NPC to improve prediction efficiency and guide individualized treatment, such as Wang's predicting system based on 8 immunomarkers (15), Yang's system based on deoxyribonucleic acid of Epstein-Barr virus (EBV-DNA) and C-reactive protein (16), and Du's system for defining patients fit for neoadjuvant chemotherapy (17). However, those prognostic models, including the one we developed in our previous work, were based on retrospective data, which might bring biases and limited clinical popularization.…”

Gemcitabine improves survival in patients with recurrent or metastatic nasopharyngeal carcinoma

“…Radiotherapy or chemoradiotherapy has become the primary treatment of early or locoregionally advanced NPC [3, 4]. However, about one-third of these patients have treatment failure due to distant metastasis [5]. The median overall survival (OS) of recurrent or metastatic NPC patients is only approximately 20 months [6].…”