Comparasion of elective nodal irradiation and involved-field irradiation in esophageal squamous cell carcinoma: a meta analysis

Abstract

It is still controversial whether radical radiotherapy in patients with esophageal squamous cell carcinoma (ESCC) still requires elective nodal irradiation (ENI), or only involved-field irradiation (IFI). In this study, a meta analysis was used to compare ENI and IFI in the treatment of ESCC, in order to provide guidance for clinical practice. Methods: Literatures on ENI and IFI in treatment of ESCC were retrieved, and the last access was June 30, 2017. A meta analysis was performed to evaluate the advantage and disadvantage of ENI and IFI. Results: Nine studies with a total of 1143 patients were included in this analysis, of those 605 patients underwent radiotherapy only, and 538 underwent radiochemotherapy. There was no significant difference in 1-, 2-, 3-year local control rate between ENI and IFI, or 1-, 2-, 3-year overall survival rates. However, the incidences of ≥ 3 grade acute esophagitis and pneumonia were significantly lower in IFI group. There was no difference in the rate of out-field recurrence/metastasis in this two groups. Conclusions: Neither local control rates nor overall survival rates between ENI and IFI groups have significant differences, but in the latter group, incidences of severe radiation esophagitis and pneumonia are significantly lower. IFI is not associated with increasement of out-field recurrence/metastasis. It is noteworthy that most of the included studies are retrospective. Therefore, a large prospective randomized study is needed for further investigation and verification.