Patterns of lymph node metastases from nasopharyngeal carcinoma:an analysis of 3100 patients based on MRI
Wang Xiaoshen*, Hu Chaosu, Ying Hongmei, He Xiayun, Shen Chunying, Zhu Guopei, Kong Lin, Ding Jianhui
*Department of Radiation Oncology, Cancer Hospital of Fudan University;Department of Oncology, Shanghai Medical College of Fudan University, Shanghai 200032, China
Abstract：Objective To investigate the patterns of lymph node metastases from nasopharyngeal carcinoma (NPC) based on magnetic resonance imaging (MRI) and to provide a basis for neck irradiation field in intensity-modulated radiation therapy. Methods From 2010 to 2013, 3100 patients newly diagnosed with NPC who underwent MRI were analyzed. All images were evaluated by the multi-disciplinary treatment group for NPC to analyze lymph node metastases. The locations of lymph nodes were determined by the RTOG consensus guidelines published in 2003. Results Of 3100 patients, 2679(86.42%) had lymph node metastases;the detailed distribution was as follows:lateral retropharyngeal region (2012 patients, 64.90%;6 patients were also in the medial group), level Ⅱb (2341 patients, 75.52%;492 had the upper border reaching half of C1 vertebra and 115 had the upper border reaching the skull base), level Ⅱa (1798 patients, 58.00%), level Ⅲ(1184 patients, 38.19%), level Ⅳ (350 patients, 11.29%;28 had the lower border beyond the RTOG recommended boundary), level Ⅴ (995 patients, 32.10%;91 had the lymph nodes beyond the RTOG recommended boundary), level Ⅰb (115 patients, 3.71%), and parotid region (40 patients, 1.29%). Extensive ipsilateral lymph node metastases were seen in patients with lymph nodes metastases in levels Ⅳ and Ⅴ, and the total numbers of involved nodes were ≥6 and 7. Skip metastasis occurred in 6 patients (0.19%). Conclusions Metastases to retropharyngeal lymph nodes are seen mainly in the lateral group but rarely in the medial group. The upper border of level Ⅱ lymph nodes should be the skull base. Lymph node metastases from NPC are in an orderly manner, and skip metastasis is rarely seen. When level Ⅳ/Ⅴ lymph nodes are involved, there might exist metastases beyond the RTOG recommended boundary. In case of extensive ipsilateral lymph node metastases, the parotid region might be involved.
Wang Xiaoshen*,Hu Chaosu,Ying Hongmei et al. Patterns of lymph node metastases from nasopharyngeal carcinoma:an analysis of 3100 patients based on MRI[J]. Chinese Journal of Radiation Oncology, 2014, 23(4): 331-335.
[1] Grégoire V, Levendag P, Ang KK, et al. CT-based delineation of lymph node levels and related CTVs in the node-negative neck:DAHANCA, EORTC, GORTEC, NCIC,RTOG consensus guidelines[J]. Radiother Oncol,2003,69:227-236. [2] 王孝深,胡超苏,吴永如,等.218例鼻咽癌颈淋巴结转移规律的影像学分析[J].癌症,2004,23:1056-1059. [3] 王孝深,胡超苏,吴永如,等.鼻咽癌颈淋巴结转移1999年影像学分区方法的局限性[J].中华放射肿瘤学杂志,2005,14:265-268. [4] Wang XS, Hu CS, Ying HM, et al. Patterns of retropharyngeal lymph node metastasis in nasopharyngeal carcinoma[J]. Int J Radiat Oncol Biol Phys,2009,73:194-201. [5] Gao Y, Zhu G, Lu J, et al. Is elective irradiation to the lower neck necessary for N0 nasopharyngeal carcinoma[J]? Int J Radiat Oncol Biol Phys,2010,77:1397-1402. [6] Li JG, Yuan X, Zhang LL, et al. A randomized clinical trial comparing prophylactic upper versus whole-neck irradiation in the treatment of patients with node-negative nasopharyngeal carcinoma[J]. Cancer,2013,119:3170-3176. [7] Feng FY, Kim HM, Lyden TH, et al. Intensity-modulated radiotherapy of head and neck cancer aiming to reduce dysphagia:early dose-effect relationships for the swallowing structures[J]. Int J Radiat Oncol Biol Phys,2007,68:1289-1298. [8] Wang X, Li L, Hu C, et al. Patterns of level Ⅱ node metastasis in nasopharyngeal carcinoma[J]. Radiother Oncol,2008,89:28-32. [9] Varoquaux A, Fakhry N, Gabriel S, et al. Retrostyloid parapharyngeal space tumors:a clinician and imaging perspective[J].Eur J Radiol,2013,82:773-782. [10] Olsen KD. Tumors and surgery of the parapharyngeal space[J]. Laryngoscope,1994,104(Suppl 63):1-28. [11] Eisbruch A, Marsh LH, Dawson LA, et al. Recurrences near base of skull after IMRT for head-and-neck cancer:implications for target delineation in high neck and for parotid gland sparing[J]. Int J Radiat Oncol Biol Phys,2004,59:28-42. [12] Grégoire V, Eisbruch A, Hamoir M, et al. Proposal for the delineation of the nodal CTV in the node-positive and the post-operative neck[J]. Radiother Oncol,2006,79:15-20.
2014, Vol. 23 
