A phase-II/III randomized controlled trial of adjuvant radiotherapy or concurrent chemoradiotherapy after surgery versus surgery alone in patients with stage-IIB/III esophageal squamous cell carcinoma

Abstract

Background: Preoperative chemoradiotherapy (CRT) followed by surgery is the most common approach for patients with resectable esophageal cancer. Nevertheless, considerable numbers of esophageal-cancer patients undergo surgery as the first treatment. The benefit of neoadjuvant therapy might only be for patients with a pathologic complete response, so stratified research is necessary. Postoperative treatments have important roles because of the poor survival rates of patients with stage-IIB/III disease treated with resection alone. Five-year survival of patients with stage-IIB/III thoracic esophageal squamous cell carcinoma (TESCC) after surgery is 20.0-28.4%, and locoregional lymph-node metastases are the main cause of failure. Several retrospective studies have shown that postoperative radiotherapy (PORT) and postoperative chemoradiotherapy (POCRT) after radical esophagectomy for esophageal carcinoma with positive lymph-node metastases and stage-III disease can decrease locoregional recurrence and increase overall survival (OS). Using intensity-modulated RT, PORT reduces locoregional recurrence further. However, the rate of distant metastases increases to 30.7%. Hence, chemotherapy may be vital for these patients. Therefore, a prospective randomized controlled trial (RCT) is needed to evaluate the value of PORT and concurrent POCRT in comparison with surgery alone (SA) for esophageal cancer. Method: This will be a phase-II/III RCT. The patients with pathologic stage-IIB/III esophageal squamous cell carcinoma will receive concurrent POCRT or PORT after radical esophagectomy compared with those who have SA. A total of 120 patients in each group will be recruited. POCRT patients will be 50.4 Gy concurrent with paclitaxel (135-150 mg/m2) plus cisplatin or nedaplatin (50-75 mg/m2) treatment every 28 days. Two cycles will be required for concurrent chemotherapy. The prescription dose will be 54 Gy for PORT. The primary endpoint will be disease-free survival (DFS). The secondary endpoint will be OS. Other pre-specified outcome measures will be the proportion of patients who complete treatment, toxicity, and out-of-field regional recurrence rate between PORT and POCRT. Discussion: This prospective RCT will provide high-level evidence for postoperative adjuvant treatment of pathologic stage-IIB/III esophageal squamous cell carcinoma. Trial registration: clinicaltrials.gov (NCT02279134). Registered on October 26, 2014.