Influence of negative lymph node in No 7 on survival of patients with middle thoracic esophageal squamous cell carcinoma.
BACKGROUND
The overall survival (OS) of patients with thoracic esophageal cancer is poor because of the high rate of lymph node metastases. However, recent studies found that the negative lymph node (LN) may also influence the patients' OS. The purpose of this study is to investigate which negative LN stations play a key role in OS prediction.


METHODS
Our study included the retrospective records of 99 patients, who were identified with middle thoracic esophageal squamous cell cancer after esophagectomy. The maximum follow-up time was 6 years. Cox regression models were employed to determine the association between the negative LN and OS of patients. After applying Kaplan-Meier method to calculate OS of patients with positive and negative LNs, the log-rank tests were used to assess the difference between them.


RESULTS
The hazard ratio of the total number of negative LNs was 0.937 (P=0.001), and the length of tumor was 1.166 (P=0.038). Multivariate regression results showed that the numbers of positive LNs in No 3 and 7 stations and negative LNs in No 109 and 7 stations were significantly related to OS, and their P-values were 0.017, 0.001, 0.020, and 0.022, respectively. The OS of the patients who had positive and negative LNs in No 7 station was significantly different (P=0.028).


CONCLUSIONS
No 7 is the most important among the negative LN stations which prolong OS. More attention should be paid to this area when making treatment plan for patients with no negative LNs identified in operation.
Cancer Center, LinYi People Hospital, Affiliated to Shandong University, School of Medicine, Jinan, Shandong Province, People's Republic of China.
Jinling
J
Zhang
Cancer Center, LinYi People Hospital, Affiliated to Shandong University, School of Medicine, Jinan, Shandong Province, People's Republic of China.
Xueyuan
X
Heng
Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, USA.
Yi
Y
Luo
Cancer Center, LinYi People Hospital, Affiliated to Shandong University, School of Medicine, Jinan, Shandong Province, People's Republic of China.
Qingxi
Q
Fu
Cancer Center, LinYi People Hospital, Affiliated to Shandong University, School of Medicine, Jinan, Shandong Province, People's Republic of China.
Zhengrong
Z
Li
Cancer Center, LinYi People Hospital, Affiliated to Shandong University, School of Medicine, Jinan, Shandong Province, People's Republic of China.
Fengyuan
F
Che
Department of Radiation Oncology (Chest Section), Shandong's Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, Jinan, Shandong Province, People's Republic of China.
Baosheng
B
Li
esophageal cancer; lymph node metastasis; prognosis