Abstract
Background
Endoscopic submucosal dissection (ESD) can be used as a less invasive treatment option for early esophageal cancer. But how to prevent lymph node metastasis is essential in these patients. This study aimed to analyze prevalence of lymph nodes metastasis for T1b thoracic esophageal squamous cell carcinoma(TESCC) patients treated in Shanghai Chest Hospital(SCH) and to propose a clinical target volume (CTV) for additional radiotherapy Clinical Target Volume design following endoscopic submucosal dissection(ESD) in these patients.
Methods
From 2012 to 2017, consecutive patients with T1b TESCC patients who underwent complete resection in SCH were identified. The prevalence of lymph-node metastasis were assessed and evaluated whether these metastasis areas would be encompassed by our proposed CTV. We proposed lymph-node stations (JEOG) 101, 104, 105, 106, 107 for upper TESCC, lymph-node stations 106, 107, 108, 1, 2, 3, 7, 8, 9, 10 for middle TESCC, and lymph-node stations110, 112, 1, 2, 3, 7, 8, 9, 10 for lower TESCC.
Results
There were 240 patients (80.4% male) who met the inclusion criteria, with a mean age of 62 ± 7 years. Of the total, 27.1%(65/240) patients presented with lymph nodes metastasis. Single lymph-node and single station lymph-node metastasis among positive nodes patients were 63.1%(41/65) and 70.8%(46/65), respectively.Tumor length exceeding 20mm and poor tumor differentiation but not age, gender, tumor position and tumor thrombus were independently associated with the risk of nodal disease. Among positive nodes patients, 89.2% (58/65) lymph-node metastasis for T1b TESCC patients could be covered by proposed CTV.
Conclusion
Prevalence of lymph node metastasis is high in patients with T1b TESCC. It seemed additional radiotherapy after ESD for those patients with high risk factors is needed to prevent lymph node metastasis. Majority positive nodes area could be covered by our proposed CTV. However, the value of radiotherapy and the proposed CTV should be investigated in further prospective studies.
Disclosure
All authors have declared no conflicts of interest.
Exploration of the Radiotherapeutic Clinical Target Volume Delineation for Gastric Cancer from Lymph Node Metastases