Pattern Of Lymph Node Metastases And Its Implication In Radiotherapeutic Clinical Target Volume In Patients With Upper Thoracici Esophageal Squamous Cell Carcinoma

PURPOSE:To study the pattern of lymph node metastases after esophagectomy in patients with upper thoracic esophageal squamous cell carcinoma (ESCC) and provide the criteria of the clinical target volume (CTV) delineation;to analyze the3-year overall survival (OS) rates of patients with upper thoracic ESCC and evaluate the effectiveness of adjuvant radiotherapy.METHODS AND MATERIALS:From January2007to January2011, total100upper thoracic ESCC patients who had undergone radical esophagectomy and84upper thoracic ESCC patients who had been treated with concurrent chemoradiotherapy(CCRT) in Shandong Cancer Hospital were retrospectively examined. All patients should contain complete history, physical examination, and endoscopy of the entire upper gastrointestinal tract. Computed tomography (CT) of the chest and the abdomen, or PET had been performed to stage these patients and evaluate the resectability of the primary tumor and to exclude distant organ metastasis. The gender, age, pathologic morphology type, T stage, length of tumor, histological differentiation, number of regional lymph nodes were examined, and number of regional lymph nodes with metastasis were recorded. The clinicopathologic factors related to lymph node metastasis were analyzed using logistic regression analysis. All patients were followed up within3years. The Kaplan-Meier method was used to calculate the OS rates.RESULTS:The rates of lymph node metastases in patients with upper thoracic ESCC were3.0%cervical,15.0%upper mediastinal,11.0%middle mediastinal,12.0%lower mediastinal, and8.0%abdominal, respectively. The length of tumor and the histological differentiation emerged as statistically significant risk factors of lymph node metastases of upper thoracic ESCC (P=0.004and P=0.001). Overall1-,2-, and3-year survival rates were86.6%,70.1%, and47.8%in patients underwent radical esophagectomy;82.8%,65.6%, and40.6%in patients treated with CCRT. There were no statistically significant differences (P=0.313). OS rate were80.0%,67.5%, and40.0%at1year,2years, and3years in patients treated with CCRT plus adjuvant bilateral supraclavicular radiotherapy;87.5%,62.5%, and41.7%in patients with CCRT alone.respectively. The results were not statistically significant differences (P=0.991).CONCLUSIONS:The length of tumor and the histologic differentiation influence the pattern of lymph node metastases in upper thoracic ESCC. These factors should be considered comprehensively to design the CTV for radiotherapy of upper thoracic ESCC. The CTV of upper thoracic ESCC may encompass correlated lymphatic drainage regions. Both radical esophagectomy and CCRT are options for treating upper thoracic ESCC, and CTV in CCRT may not encompass the bilateral supraclavicular area.