Jingling Zhang¹  Zhongyao Jia¹  Shoufeng Wang¹  Baosheng Li²

¹ Department of Oncology,Linyi People’s Hospital Affiliated with Shandong University

² Departmentof Radiotherapy, Shandong Cancer Hospital, Jinan

Objective：The overall survival is poor for patients with thoracicesophageal cancer. The major reason is the high rate of lymph node metastases.However, recent studies found that the number of negative lymph nodes couldalso influence the outcome. The purpose of this study is try to assess whichgroups of lymph negative nodes play the key role in influencing the outcome. Method：Ninth-nine patients who received operation withoutneo-adjuvant chemotherapy were included in this retrospective study, and allthe patients were identified to have the middle thoracic esophageal squamouscell cancer. The maximum follow-up time was 5 years. All resected lymph nodeswere analyzed by two pathologists independently. Seventh-four of 99 patientsreceived postoperative therapy. Cox regression models were used to determinethe association between the number of negative lymph nodes and overall survival(OS) of patients. Kaplan-Meier method was used to estimate OS separatelyfor patients with positive and negative lymph nodes in the No.7 and No.109groups, and the log-rank tests was used to assess the difference between them. Result：The Hazard Rate of the total number of negativelymph nodes influencing outcome was 0.938 (P-value=0.001),and the length of tumor was 1.166 (P=0.038).Multivariate regression results showed that the number of positive lymph nodesin 3, 7 groups and negative lymph nodes in 7,109 had significantly related toOS, and the P-value were 0.017,0.001, 0.020 and 0.022 respectively. In addition, the number of negative lymphnodes in 103 and 107 we identified to be independently associated with OS. TheOS between the patients who had positive and negative lymph nodes in NO.7 groupwas significantly different (P-value=0.028).Conclusion：This study identified that NO.7 and NO.109 were themost important groups in negative lymph nodes influencing OS in the patientswith thoracic esophageal squamous cell carcinoma. It implied that moreattention on these two areas in treatment planning of postoperativeradiotherapy could benefit outcome.

KeyWords：esophageal squamous cell carcinoma  negative lymph