Prognostic Value of Cervical Nodal Necrosis in Nasopharyngeal Carcinoma: Analysis of 1800 Patients with Positive Cervical Nodal Metastasis at MR Imaging

Abstract

Purpose:To evaluate the prognostic value of cervical nodal necrosis (CNN) in patients with nasopharyngeal carcinoma (NPC) with magnetic resonance (MR) imaging. Materials and Methods:This was an institutional review board-approved retrospective study of 1800 patients with newly diagnosed stage T1, 4N1, 3M0 NPC who were treated with definitive radiation therapy, with or without chemotherapy, between January 2007 and December 2009; the requirement to obtain informed consent was waived. MR images were reviewed to assess lymph node status, and patients were divided into CNN and non-CNN groups. The overall survival, disease-free survival, regional relapse-free survival (RRFS), and distant metastasis-free survival (DMFS) were calculated with the Kaplan-Meier method, and differences were compared by using the log-rank test. Results:The incidence of CNN was 44.0% (792 of 1800). After the median follow-up period of 53 months, the 5-year overall survival, disease-free survival, RRFS, and DMFS rates of the CNN and non-CNN groups were 78.8% and 91.8%, 78.2% and 91.2%, 78.6% and 91.8%, and 78.4% and 91.6%, respectively (for all rates, P , .001). The distant metastasis rate was 18.7% (148 of 792) for the CNN group versus 4.6% (46 of 1008) for the non-CNN group (P , .01). Subgroup analysis revealed similar survival outcomes between stage N1 disease with CNN and stage N2 disease without CNN, stage N2 disease with CNN, and stage N3 disease regardless of CNN. CNN, T stage, N stage, age older than 44 years, and male sex were significant independent negative prognostic factors for overall survival, disease-free survival, RRFS, and DMFS. Conclusion:CNN is an independent negative prognostic factor in patients with NPC, and it may be appropriate to investigate whether N stage should be upgraded by one level in patients with CNN.q RSNA, 2015

Sentinel Node Necrosis Is a Negative Prognostic Factor in Patients with Nasopharyngeal Carcinoma: A Magnetic Resonance Imaging Study of 252 Patients

“…In a study of 786 patients with npc and positive cervical lymph nodes, Mao et al 9 reported that the incidence of lymph node necrosis was only 26.5%. In our study, the incidence of lymph node necrosis was much higher (43.3%, 91 of 210 patients) and similar to the incidence described by Lan et al 11 . In the study by Mao et al 9 , lymph node necrosis did not have a significant association with survival in npc patients; however, that result might reflect the analysis of a relatively small cohort.…”

“…Those results indicate that the retropharyngeal lymph nodes and the cervical level ii nodes might both be the first-echelon nodes in npc, perhaps partly because the lymphatic vessels of the nasopharynx drain in two general directions, lateral and medial 5,13 . The primary drainage is the lateral pathway, which drains the lateral nasopharynx and flows into the lateral half of the upper internal jugular chain or into the lateral retropharyngeal lymph node 11 .…”

“…All patients underwent a pre-treatment evaluation that consisted of a complete history, physical examination, hematology and biochemistry profiles, mri of the nasopharynx and neck, chest computed tomography (ct), and abdominal sonography; patients with T3 or T4 disease, low cervical metastasis, or any lymph node exceeding 4 cm in size also underwent whole-body bone scan or combined positronemission tomography and ct 11 . Magnetic resonance images of the complete nasopharynx and cervical area were used to evaluate lymph node status 11 .…”

Cervical nodal necrosis is an independent survival predictor in nasopharyngeal carcinoma: an observational cohort study

“…We therefore used both contrast-enhanced CT and MRI to improve both accuracy and sensitivity of imaging results, following recommendations set forth by King et al,17 wherein a cervical node was diagnosed as necrotic if there was a focal area of low attenuation with or without a surrounding rim of enhancement on CT imaging and if there was a focal area of high signal intensity on T2-weighted images or a focal area of low signal intensity on T1-weighted images (with or without a surrounding rim of enhancement on MRI). While the incidence of CNN in our study population was 45% (85 of 189 patients), other studies have reported CNN ranges from 20% to 44% in NPC patients 17,23,24,29. Importantly, our study excluded early-stage patients, who were included in other studies; 45% reported herein is therefore reasonable.…”

“…Multivariate analysis identified CNN as an independent, negative prognostic factor for PFS and OS. Recently, a study by Lan et al24 evaluated the prognostic value of CNN and determined that CNN negatively affected OS, DFS, RRFS, and DMFS in NPC patients. A study by Tang et al26 also demonstrated that necrotic RLN metastases have a negative effect on treatment failure, distant failure, and locoregional recurrence in NPC patients.…”