MRI in exploring the spread pattern of retropharyngeal lymp node metastases in nasopharyngeal carcinoma / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>The purpose of this study is to investigate the incidence, distribution and spread pattern of retropharyngeal lymph node (RLN) metastasis in the patient with nasopharyngeal carcinoma (NPC) using magnetic resonance imaging (MRI).</p><p><b>METHODS</b>MRI data of 294 patients with newly diagnosed NPC were reviewed retrospectively. Criteria for RLN metastasis were the minimal axial dimension of > or = 6 mm, or the presence of nodal necrosis.</p><p><b>RESULTS</b>RLN involvement was detected in 165 (56.1%) patients. The incidence of metastatic lateral RLN decreased gradually from C1 to C3 level. A significantly higher incidence of metastatic RLN was observed in the patients with cancerous involvement of oropharynx, nasal cavity, pre-styloid parapharyngeal space, post-styloid parapharyngeal space or with cervical lymph node metastasis. Thirty-one patients (10.5%) had metastatic RLN only, and 54 (18.4%) showed metastatic cervical lymph nodes only, but 134 (45.6%) exhibited an involvement of both the RLN and cervical lymph node. A significantly lower incidence of metastatic RLN was found in T1, N0, and stage I disease.</p><p><b>CONCLUSION</b>The incidence of metastatic lateral retropharyngeal lymph node decreases gradually from C1 to C3 level. Metastatic retropharyngeal lymph node is associated with cancerous involvement of surrounding tissue by primary tumor or with cervical lymph node metastasis. Retropharyngeal lymph node or cervical level II node can be considered equally as the first station of nodal metastasis in nasopharyngeal carcinoma.</p>