Abstract:
Objective To investigate the prognosis of cervical and posterior to level Ⅴ (PLV) lymph node metastasis and discuss further updates on neck levels and N stages for nasopharyngeal carcinoma (NPC).
Methods A total of 406 pathologically diagnosed NPC cases from December 2011 to June 2016 were retrospectively analyzed. SPSS 20.0 was used to analyze the prognosis of patients with cervical and PLV lymph node metastasis.
Results In the 406 cases, the 5-year overall survival (OS), progression-free survival (PFS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were 75.0%, 63.4%, 87.2%, and 81.8%, respectively. The 3-year OS, PFS, LRFS, and DMFS of patients with node involvement of PLV were 51.5%, 22.7%, 90.0%, and 41.3%, respectively. For the N3 stage, the 3-year OS, PFS, LRFS, and DMFS with or without PLV involvement were 43.9% and 84.7% (P=0.002), 12.9% and 55.4% (P= 0.006), 88.9% and 80.3% (P=0.649), and 33.0% and 85.9% (P < 0.001), respectively. Univariate analysis showed that N stage was a prognostic factor for OS, PFS, and DMFS (P < 0.05). Multivariate analysis demonstrated that PLV was an independent prognostic factor for DMFS (P < 0.05).
Conclusion Patients with NPC with PLV node involvement exhibited poor prognosis and an increased risk of distant metastasis. Thus, PLV should be a new neck node level for head and neck tumors.