Purpose:We investigate the use of static angle tomotherapy(TomoDirect)for the treatment of esophageal cancer with the intention to test the feasibility.Methods:Nine patients for locally advanced esophageal cancer with radical intent were planned for TomoDirect(TD),Helical tomotherapy(HT)and IMRT.HT plans employed full helical arc,while TD plans had five static-port angles same as IMRT.Dose-volume-histogram(DVH),dose conformity and dose homogeneity were analyzed to evaluate the plan quality.Treatment time and monitor units were used to assess delivery efficiency.Results:All the plans can satisfy the clinical requirement.TD and HT plans showed significant improvement over IMRT plans in terms of OAR dose and PTV dose conformity(p=0.001 and p<0.002)and homogeneity(p=0.002 and p<0.001).Mean V5 of lungs was slightly reduced by IMRT(58.1%)plans compared to TD(58.6%)and HT(58.6%)plans,but there was no significantly difference.Mean V20 and V30 of lungs were significant improved by TD(19.6%,p=0.001 and 9.3%,p<0.001)and HT(18.5%,p<0.001 and 9.1%,p=0.003)plans in comparision with IMRT(24.3%and 11.2%)plans.Mean lung dose for TD(11.5 Gy,p=0.018)and HT(11.2 Gy,p=0.004)plans were also reduced compared to IMRT(12.2 Gy)plans.The improvements of lungs for HT plans came at the cost of higher averaged doses to the heart,while there were no significant difference for averaged dose of heart between TD and IMRT plans.The Cord and Cord PRV had almost the same maximum dose.The treatment time and machine monitor unit of TD plans reduced by 12.6%and 37.5%compared with HT plans,respectively.IMRT plans had the shortest treatment time.Conclusion:The TD technique is a feasible method to treat esophageal cancer.It not only can shorten the treatment time and improve radiation efficiency compared with HT,but also provide an advantage in terms of the mean V20,V30 and mean dose of lungs in comparision with IMRT.