应用磁共振成像技术探讨鼻咽癌咽后淋巴结转移的规律

目的采用磁共振成像(MRI)技术,探讨鼻咽癌咽后淋巴结转移的发生率、分布和转移规律。方法回顾性分析294例经病理证实的初治鼻咽癌患者的磁共振(MR)资料,分析咽后淋巴结转移与鼻咽癌原发灶侵犯部位、颈部淋巴结转移和鼻咽癌分期的关系。结果有165例(56.1%)患者发现有咽后淋巴结转移。从C1到C3水平,外侧组咽后淋巴结转移率呈递减趋势。口咽、鼻腔、茎突前后间隙侵犯和颈部淋巴结转移患者的咽后淋巴结转移率较高。294例患者中,有219例(74.5%)出现咽后淋巴结和颈部淋巴结转移,其中31例(10.5%)仅出现咽后淋巴结转移,54例(18.4%)仅出现颈部淋巴结转移,134例(45.6%)同时出现咽后和颈部淋巴结转移。T1、N0及Ⅰ期的患者咽后淋巴结转移率较低。结论咽后淋巴结转移与鼻咽癌早期局部侵犯及上颈链、颈后三角的淋巴结转移密切相关。咽后淋巴结和Ⅱ区颈部淋巴结均为是鼻咽癌淋巴结转移的首站。

MRI in exploring the spread pattern of retropharyngeal lymp node metastases in nasopharyngeal carcinoma

OBJECTIVE: 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). METHODS: 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. RESULTS: 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. CONCLUSION: 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.