Abstract: 【Abstract】Objective:To investigate the clinical value of preoperative serum carcinoembryonic antigen (CEA) detection in the prediction of esophageal cancer lymph node metastasis.
Methods:The clinical data of 111 patients with esophageal cancer who were admitted to the Chaoyang Hospital of Capital Medical University between December 2010 and January 2014 were retrospectively analyzed. Patients received preoperative serum CEA examination and enhanced CT of the chest. The surgical procedures were selected according to the condition of patients, including radical resection of esophageal cancer via left thoracic approach, transabdominal right thoracic approach (open and laparoscopic surgeries), cervicothoracicabdominal triple incision (open and laparoscopic surgeries) and transabdominal incision. The international standard was used for tumor location and TNM stage of esophageal cancer. The count data and comparison of ordinal data in the univariate analysis were analyzed using the chisquare test, Fisher exact probability and ranksum test, respectively. The multivariate analysis was done using the stepwise logistic regression. The ROC curve was used for evaluating diagnostic value of serum CEA examination and enhanced CT of the chest. All the 111 patients were divided into 4 groups according to the interquartile range results of the CEA examination, and the lymph node metastasis rates of 4 groups were compared by the chisquare test.
Results:All the 111 patients underwent successful radical resection of esophageal cancer after preoperative serum CEA detection and enhanced CT of the chest, including 40 via left thoracic approach, 56 via transabdominal right thoracic approach, 8 via cervicothoracicabdominal triple incision and 7 via transabdominal incision. There were 3 patients with upper thoracic esophageal cancer, 52 with middle thoracic esophageal cancer, 36 with lower thoracic esophageal cancer and 20 with cancer of gastroesophageal junction. The postoperative pathological type included 84 squamous cell carcinomas, 23 adenocarcinomas and 4 other carcinomas. There were 44 patients with negative lymph node metastases and 67 with positive lymph node metastases. The positive rate of elevated serum CEA in the 111 patients was 36.04%(40/111). Tumor location, pathological type and N stage of tumor were clinical pathological factors affecting the positive rate of serum CEA of patients (Z=6.815, 6.608, 16.928, P<0.05). N stage of tumor was an independent risk factor affecting the positive rate of serum CEA of patients by multivariate analysis ［OR=2.206, 95% confidence interval (CI): 1.370-3.552, P<0.05］. The T stage of tumor and serum CEA level were risk factors affecting lymph node metastasis of esophageal cancer by univariate analysis (Z=18.971, χ²=10.081, P<0.05), and those were also independent risk factors affecting lymph node metastasis of esophageal cancer by multivariate analysis (OR= 3.558, 3.936, 95% CI: 1.798-7.041, 1.480-10.469, P<0.05). The lymph node metastasis rates of esophageal cancer were 46.43%, 48.28%, 55.56% and 92.59% when CEA level≤1.75 μg/L, 1.75 μg/L<CEA level≤2.68 μg/L, 2.68 μg/L<CEA level≤ 4.21 μg/L and CEA level>4.21 μg/L by the stratified analysis, respectively, with a significant difference among the 4 groups (χ²=16.026, P<0.05). The areas under the curve of CEA level and enhanced CT of the chest for lymph node metastasis were 0.687 (95% CI: 0.590- 0.785) and 0.689 (95% CI: 0.591-0.788) by ROC curve, which were significantly different from the area under the guides (P<0.05). The areas under the curve of CEA level and enhanced CT of the chest for lymph node metastasis were 0.785 (95%CI: 0.697-0.873, P< 0.05).
Conclusions:Serum CEA detection not only has certain predictive value for lymph node metastasis of esophageal cancer, but has a higher predictive value combined with enhanced CT of the chest. There is a risk of lymph node metastasis for patients with deep tumor invasion and elevated CEA level, and the range of lymph node dissection should be expanded.