Comparative Evaluation of the Quality of Irradiation Planning for Esophageal Cancer at the Clinical Accelerators Clinac iX and Halcyon

   Purpose: To compare the quality of irradiation planning for patients with esophageal cancer using Clinac iX (Varian) electron accelerators with external gantry and Halcyon (Varian). Compare quantitative indicators of irradiation plans for different algorithms and versions.

   Material and methods: A comparative assessment of the quality of irradiation planning for 90 patients with cancer of the esophagus was carried out using the indices of dose homogeneity and conformity within the target according to the data of dose-volume histograms and dose loads on critical organs. The comparison was carried out for two models of accelerators Clinac iX (Varian) with an external gantry and tunnel type Halcyon (Varian). The results of calculations of irradiation plans using different versions and algorithms for calculating planning systems are compared.

   Results: A comparison of the quantitative characteristics of the exposure plans made it possible to designate the IMRT technology as the preferred one in the treatment of esophageal cancer using accelerators of both types, with external and built-in gantry. At the same time, the influence of calculation algorithms and versions of the SP on the indices of homogeneity, conformity and dose loads on critical organs is not expressed, and the calculation results are comparable within the error.

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