What is the optimal radiation dose for non-operable esophageal cancer? Dissecting the evidence in a meta-analysis

• Published in: Oncotarget Vol. 8; no. 51; pp. 89095 - 89107
• Main Authors: Chen, Yong, Zhu, Hui-Ping, Wang, Tao, Sun, Chang-Jiang, Ge, Xiao-Lin, Min, Ling-Feng, Zhang, Xian-Wen, Jia, Qing-Qing, Yu, Jie, Yang, Jian-Qi, Allgayer, Heike, Abba, Mohammed L, Zhang, Xi-Zhi, Sun, Xin-Chen
• Format: Journal Article
• Language: English
• Published: United States Impact Journals LLC 24.10.2017
• Subjects: Meta-Analysis; meta-analysis; chemoradiotherapy; esophageal cancer; radiation dose; survival benefit
• ISSN: 1949-2553; 1949-2553
• DOI: 10.18632/oncotarget.18760

The standard radiation dose 50.4 Gy with concurrent chemotherapy for localized inoperable esophageal cancer as supported by INT-0123 trail is now being challenged since a radiation dose above 50 Gy has been successfully administered with an observable dose-response relationship and insignificant untoward effects. Therefore, to ascertain the treatment benefits of different radiation doses, we performed a meta-analysis with 18 relative publications. According to our findings, a dose between 50 and 70 Gy appears optimal and patients who received ≥ 60 Gy radiation had a significantly better prognosis (pooled HR = 0.78, = 0.004) as compared with < 60 Gy, especially in Asian countries (pooled HR = 0.75, = 0.003). However, contradictory results of treatment benefit for ≥ 60 Gy were observed in two studies from Western countries, and the pooled treatment benefit of ≥ 60 Gy radiation was inconclusive (pooled HR = 0.86, = 0.64). There was a marginal benefit in locoregional control in those treated with high dose (> 50.4/51 Gy) radiation when compared with those treated with low dose (≤ 50.4/51 Gy) radiation (pooled OR = 0.71, = 0.06). Patients that received ≥ 60 Gy radiation had better locoregional control (OR = 0.29, = 0.001), and for distant metastasis control, neither the > 50.4 Gy nor the ≥ 60 Gy treated group had any treatment benefit as compared to the groups that received ≤ 50.4 Gy and < 60 Gy group respectively. Taken together, a dose range of 50 to 70 Gy radiation with CCRT is recommended for non-operable EC patients. A dose of ≥ 60 Gy appears to be better in improving overall survival and locoregional control, especially in Asian countries, while the benefit of ≥ 60 Gy radiation in Western countries still remains controversial.