A comparative study of failure patterns of definitive treatment of esophageal cancer with elective nodal irradiation and involved-field irradiation

Objective To compare the failure pattern between esophageal cancer patients receiving definitive elective nodal irradiation (ENI) and involved-field irradiation (IFI) and to investigate the reasons and influential factors for locoregional recurrence and metastasis.Methods A retrospective analysis was performed on the clinical data of 245 patients with esophageal cancer who received definitive radiotherapy in our hospital from January 2006 to December 2012.One hundred and twenty-six patients received ENI,and the other 119 patients received IFI.Failure patterns were analyzed after treatment.Locoregional failures included local esophageal lesion uncontrol or recurrence and regional lymph node recurrence or metastasis.Distant metastases included distant organ metastasis and distant lymph node metastasis.Comparison of failure pattern between the two therapies was made by chi-square test.Results One hundred and sixty-three patients had failure after treatment.Locoregional failure was observed in 92 patients,distant metastasis in 36 patients,and locoregional failure plus distant metastasis in 35 patients.The 1-,3-,and 5-year overall failure rate for the ENI group were 35.4％,62.5％,and 69.0％,respectively,versus 46.5％,71.5％,and 81.5％ for the IFI group (P =0.036).The 1-,3-,and 5-year locoregional failure rates for the ENI group were 29.9％,48.4％,and 50.0％,respectively,versus 39.6％,62.1％,and 71.4％ for the IFI group (P =0.003).Conclusions For esophageal cancer patients receiving definitive radiotherapy,ENI can significantly reduce locoregional failures and increase locoregional control,thus improving the long-term survival. Key words: Esophageal neoplasms/radiotherapy;  Elective nodal prophylactic irradiation; Involved-field irradiation;  Failure mode