Prognostic value of extracapsular spread of regional lymph nodes in nasopharyngeal carcinoma with 3DCRT based on magnetic resonance imaging

Abstract

Objective To evaluate the prognostic value of the extracapsular spread (ECS) of regional lymph nodes in nasopharyngeal carcinoma (NPC) based on magnetic resonance imaging. Methods A retrospective review was performed for 477 previously untreated patients with NPC who were treated in Yuebei People′s Hospital from January 2009 to December 2013.Univariate and multivariate survival analyses were performed to identify the prognostic value of ECS in NPC. Results There were 216 patients with ECS and 261 patients without ECS, and the median survival of the two groups of patients was 38.5 months and 39.0 months, respectively. The 3-year overall survival (OS), progression-free survival (PFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) rates of the patients with ECS versus those without ECS were 81.9% versus 90.7%, 65.8% versus 85.0%, 87.8% versus 95.8%, and 80.3% versus 92.9%, respectively (all P=0.000). The univariate analysis showed that N stage and ECS were important prognostic factors for OS, PFS, LRFS, and DMFS in NPC patients (P=0.000-0.004), and T stage and TNM stage were associated with OS, PFS, and DMFS (all P=0.000). The multivariate analysis using the Cox regression model showed that T stage was an independent prognostic factor for the survival of NPC patients, and ECS was an important prognostic factor for PFS, LRFS, and DMFS. Conclusion ECS of regional lymph nodes is a risk factor for local recurrence or distant metastasis in patients with NPC. Key words: Nasopharyngeal neoplasms/three-dimensional radiotherapy; Neoplasm metastasis, lymph nodes; Prognosis