Background: For treatment of esophageal carcinoma, the optimal postoperative radiotherapy target volume after three-field lymph node dissection(3-FLD) had not been determined. We analyzed local recurrence pattern of thoracic esophageal carcinoma and risk factors of lymph node recurrence after 3-FLD without prophylactic radiotherapy.   Methods: We reviewed 1282 patients with thoracic esophageal squamous cell carcinoma(ESCC) who were treated with 3-FLD without radiotherapy from 2010 to 2018 and analysed local recurrence patterns and risk factors of lymph node recurrence, in order to provide a reference for determination of the radiotherapy target volume for thoracic ESCC. Results: The lymph node recurrence accounted for 91.0% of treatment failures. The mediastinal, cervical and abdominal lymph node recurrence rates were 85.2%, 36.5% and 22.4%, respectively,(x 2 =264.596, P=0.000). The superior, middle and inferior mediastinal lymph node recurrence rates were 67.54%, 27.87% and 0.98%, respectively(x 2 =313.600, P=0.000). In a multivariate analysis, Cevical metastases were significantly associated with N stage and Preoperative cevical lymph node status. Abdominal metastases were significantly associated with the number of preoperative abdominal lymph node metastases( LNM), tumor location and N stage. Conclusions: The main pattern of local-regional recurrence might be lymph node metastasis after radical 3-FLD without radiotherapy in esophageal carcinoma. The dangerous lymph node recurrence regions included neck, superior and middle mediastinum. Radiologist might took the number of pre-operative abdominal lymph nodes and tumor location into consideration while delineating the target area of abdominal region .

The authors have declared no competing interest.

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