Objective  To investigate the risk factors of cervical lymph node metastasis in middle and lower esophageal squamous cell carcinoma and construct a diagnostic model to provide clinical strategies for the rational selection of surgical methods.

  Methods  A total of 240 patients with middle and lower esophageal squamous cell carcinoma, who underwent radical esophagectomy and three-field lymph node dissection at The Fourth Hospital of Hebei Medical University from January 2015 to June 2020 were selected as the observation subjects. According to the postoperative pathology, the patients were assigned into the cervical lymph node metastasis group and non-cervical lymph node metastasis group. Multivariate Logistic regression was used to analyze the independent risk factors of cervical lymph node metastasis, and receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance.

  Results  Among 240 patients, 62 (25.8%) had cervical lymph node metastasis. Multivariate Logistic regression analysis revealed that the largest tumor diameter, paraesophageal lymph node status, recurrent laryngeal nerve lymph node status, and cervical lymph node metastasis status diagnosed by computed tomography (CT) were independent risk factors for cervical lymph node metastasis in middle and lower esophageal squamous cell carcinoma. The diagnostic model: P=1/(1+exp(-(-3.764+ 0.361× largest tumor diameter+1.281×paraesophageal lymph node status+1.614×recurrent laryngeal nerve lymph node status+1.155×cervical lymph node metastasis status diagnosed by CT))). The negative and positive predictive values were 89.89% and 45.16%, respectively. The area under the ROC curve of the diagnostic model constructed according to the independent risk factors was 0.827 (95%CI: 0.767–0.886), and the Youden index was 0.530, corresponding to a sensitivity and specificity of 70.97% and 82.02%, respectively.

  Conclusions  The largest tumor diameter, paraesophageal lymph node status, recurrent laryngeal nerve lymph node status, and cervical lymph node metastasis status diagnosed by CT are independent risk factors for cervical lymph node metastasis of middle and lower esophageal squamous cell carcinoma. The diagnostic model established on this basis has a certain clinical application value.