Patterns of failure after complete resection of thoracic esophageal squamous cell carcinoma: implications for postoperative radiation therapy volumes

Abstract

Objective To analyze intrathoracic or extrathoracic recurrence pattern after surgical resection of thoracic esophageal squamous cell carcinoma (TESCC) and its help for further modify and improvement on the target of postoperative radiation therapy. Methods One hundred and ninety-five patients who had undergone resection of TESCC at the Cancer Hospital,Chinese Academy of Medical Sciences enrolled from April 1999 to July 2007.Sites of failure on different primary location of esophageal cancer were documented.Results Patients with upper or middle thoracic esophageal cancer had higher proportion of intrathoracic recurrence.Patients with lower thoracic esophageal cancer had more intrathoracic reccurence and abdominal lymph node metastatic recurrence.Histological lymph node status has nothing to do with intrathoracic recurrence,supraclavicular lymph node ( SLN ) metastasis or distant metastasis ( χ2 =1.58,0.06,0.04,P =0.134,0.467,0.489,respectively),whereas the chance of abdominal lymph node metastases in N positive patients was significantly higher than that in N0 patients (28.7％: 10.6％,χ2 =9.94,P =0.001 ),and so did in middle thoracic esophageal cancer ( 20.0％: 5.6％,χ2 =5.67,P =0.015). Anatomic recurrence rate of patients with proximal resection margin no more than 3 cm was significantly higher compared to those more than 3 cm (25.0％: 11.3％,χ2=5.65,P=0.019).Conclusions Mediastinum is the most common recurrence site.According to recurrence site,the following radiation targets are recommended:when tumor was located at the upper or middle thoracic esophagus with negative N status,the mediastinum,the tumor bed and the supraclavicular region should be included as postoperative RT target;when tumor was located at the middle thoracic esophagus with positive N or located at the lower thoracic esophagus,the abdominal lymph node should be added.If the proximal resection margin was no more than 3 cm,the anastomotic-stoma should be included. Key words: Esophageal neoplasms/surgery; Postoperative sites of failure; Radiotherapy target volumes