The patterns of metastatic cervical nodes in 779 cases of nasopharyngeal carcinoma / 中国癌症杂志

ABSTRACT

Background and purpose: Cervical nodal metastasis in nasopharyngeal carcinoma plays an important role in the definition of radiotherapy area and clinical staging, it is also one of the main factors influencing prognosis. So this study was designed to explore the pattern of metastatic lymph nodes for patients with nasopharyngeal carcinoma, which may provide a basis for clinical treatment and research. Methods: From Jun. 2005 to Sep. 2007,779 histologically diagnosed nasopharyngeal carcinoma patients had routine MRI scan before radiation therapy at Fujian Provincial Cancer Hospital. Diagnostic radiologists and radiation oncoiogists together assessed the nodal distribution according to the guideline CT-hased delineation of lymph node levels. Then, Chi-sqnare test was used to analyze the correlation between T stage and nodal metastasis rate and between nodal diameter and nodal extracapsular invasion. Results: Of 779 patients, 592(76.0%) had nodal involvement. The distribution was as follows 1 in level Ⅰ,384 in level Ⅱa, 499 in level Ⅱ_b, 184 in level Ⅲ, 33 in level Ⅳ, 67 in level V_a, 21 in level V_b, 597 in retropharynx.In these patients, a total of 1 479 postive nodes, including 973 (65.79%) extracapsular spread nodes, were detected.The rate of nodal extracapsular invasion was higher when the axial diameter increased. Leap metastasis rate was 1.0%. No significant correlation was found between T stage and nodal involvement. Conclusion: The level Ⅱ and retropharyngeal node were the most frequently involved regions, they had similar metastatic rate and were both the first echo node to metastases of nasopharyngeal carcinoma. Level Ⅰ metastasis was lower. The proportion of extracapsular spread of metastatic lymph nodes increased with axial diameter of lymph nodes-dependent. The cervical node involvement of nasopharyngeal carcinoma was spread orderly down the neck, and the incidence of skip metastasis is rare. The relationship between T stage and nodal involvement has no statistical significance.