Late-course accelerated Hyperfractionation vs. Conventional Fraction Radiotherapy under precise technology plus Concurrent Chemotherapy for Esophageal Squamous Cell Carcinoma: comparison of efficacy and side effects

Background: The accelerated reproliferation of esophageal squamous cell carcinoma (ESCC) after radiation contributes to conventional fraction radiotherapy (CFRT) failure. Late course accelerated hyperfractionated radiotherapy (LCAHFRT) can improve the long-term survival of esophageal cancer patients in China but is associated with a high rate of side effects due to the large exposure field of two-dimensional treatment and drug toxicity. Intensity-modulated radiotherapy (IMRT) can increase the tumor dose while decreasing the normal tissue dose. Therefore, we compared the outcomes and side effects of LCAHFIMRT plus concurrent chemotherapy (CT) and CFIMRT plus CT for ESCC. Methods and Materials: Between 2013 and 2016, 114 eligible patients with ESCC were recruited and randomly assigned to receive LCAHFIMRT+CT (58 patients) or CFIMRT+CT (56 patients) by a linear accelerator (6-MV X-ray) under image guidance. Two cycles of CT with cisplatin and docetaxel were also administered. Results: The complete response (CR) rates were 79.3% and 61.8% in the LCAHFIMRT+CT and CFIMRT+CT groups, respectively (P=0.041). The median duration of local control times was 31.0±1.9 months for the LCAHFIMRT+CT group and 24.0±3.3 months for the CFIMRT+CT groups,and the 1-, 2-, and 3-year local control rates were 86.2%, 63.8%, and 41.4% and 85.7%, 51.8%, and 32.1% for the LCAHFIMRT+CT and CFIMRT+CT groups (P=0.240), respectively. The median survival times were 34.0±1.1 months for the LCAHFIMRT+CT group and 28.0.0±3.7 months for the CFIMRT groups,and the 1-, 2-, and 3-year survival rates were 87.9%, 74.1%, and 44.8% and 87.5%, 60.7%, and 39.3% for the LCAHFIMRT+CT and CFIMRT+CT groups, respectively (P=0.405). The incidence of side effects was not significantly different between the two groups. Local recurrence and uncontrolled disease resulted in more deaths in the CFIMRT+CT group than in the LCAHFIMRT+CT group (58.9% vs. 39.7%) (P=0.040). Conclusion: For ESCC patients, LCAHFRT delivered by image-guided intensity-modulated techniques Plus Concurrent Chemotherapy with cisplatin and docetaxel keeps safety and high CR rate, as well as local control and long-term survival rates.