Department of Radiation Oncology, The General Hospital of Western Theater Command, Chengdu, Sichuan Province, 610083, PR China.
Department of Medical Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, 610041, PR China.
BMC Cancer. 2020 Jul 17;20(1):667. doi: 10.1186/s12885-020-07146-z.
Lymph node metastasis in the cervical region posterior to level V (PLV) can occurs in patients with nasopharyngeal carcinoma (NPC), but the significance of lymph node metastasis in this region and the delineation of the radiotherapy target area have not been reported. We aimed to explore the distribution pattern and prognosis of metastatic lymph nodes in the PLV region in patients with NPC.
We retrospectively studied 605 cases of NPC diagnosed by pathological detection from December 2011 to November 2017. The nodal distribution at each level was assessed in accordance with the Radiation Therapy Oncology Group (RTOG) guidelines proposed in 2013. The central points of the metastatic lymph nodes of the PLV region in the patients were recreated proportionally on the CT images of a standard patient with N0 NPC in reference to the normal anatomy of the PLV area. The correlation between the PLV region and the other levels, the nodal location, and the characteristics and prognosis of the PLV region were analyzed.
Lymph node metastasis occurred in 557 (92.06%) of 605 patients. There were 30 patients (4.95%) with lymph node metastasis in the PLV region. A total of 49 metastatic lymph nodes from the PLV region were counted, and the mean vertical distance of the central point of each lymph node from the anterior surface of the trapezius muscle was 14 mm. Linear regression correlation analysis suggested that lymph node metastasis in the PLV region was associated with ipsilateral level IVa (P = 0.018), level Va, level Vb, and level Vc lymph node metastasis (all P < 0.001). The 5-year OS, PFS, LRFS, and DMFS of 29 patients with lymph node metastasis in the PLV region were 41.6, 27.7, 89.1, and 47.3%, respectively. Multivariate analysis showed that lymph node metastasis in the PLV region was an independent prognostic factor for DMFS (P < 0.05).
NPC patients with lymph node metastasis in the PLV region had a poor prognosis and a high risk of distant metastasis. We recommend that the margin of the PLV region may be a new cervical lymph node segment for NPC.
颈后区第五颈椎水平（PLV）的淋巴结转移可发生于鼻咽癌（NPC）患者中，但该区域淋巴结转移的意义及放疗靶区的勾画尚未见报道。本研究旨在探讨 NPC 患者 PLV 区域转移性淋巴结的分布模式和预后。
回顾性分析 2011 年 12 月至 2017 年 11 月间经病理证实的 605 例 NPC 患者。根据 2013 年放射治疗肿瘤学组（RTOG）提出的指南评估各水平的淋巴结分布情况。根据 PLV 区域的正常解剖结构，参照无淋巴结转移 NPC 标准患者的 CT 图像，按比例重建 PLV 区域转移性淋巴结的中心点。分析 PLV 区域与其他水平、淋巴结位置以及 PLV 区域的特征和预后之间的相关性。
605 例患者中，557 例（92.06%）发生淋巴结转移，其中 30 例（4.95%）发生 PLV 区域淋巴结转移。共检出 49 枚 PLV 区域转移性淋巴结，每个淋巴结中心点距斜方肌前缘的垂直距离平均为 14mm。线性回归相关性分析提示，PLV 区域淋巴结转移与同侧 IVa 区（P=0.018）、Va 区、Vb 区和 Vc 区淋巴结转移显著相关（均 P<0.001）。29 例 PLV 区域淋巴结转移患者的 5 年 OS、PFS、LRFS 和 DMFS 分别为 41.6%、27.7%、89.1%和 47.3%。多因素分析显示，PLV 区域淋巴结转移是 DMFS 的独立预后因素（P<0.05）。
NPC 患者 PLV 区域淋巴结转移预后差，远处转移风险高。我们建议 PLV 区域可能是 NPC 新的颈淋巴结区。
