Multiaxis and overcenterable conformation radiation therapy for esophageal cancer

The authors applied conformation radiation therapy for esophageal cancer, using the radiation planning system, MODULEX, which involves two-axis conformation radiation therapy with over centrable multileaf collimators. Considering two target volumes near the tumor volume, each isocenter was determined out of each target volume. Better dose distribution with lower dose to the spinal cord was obtained for esophageal tumor. Dose histogram was also calculated on CT imaging, and the irradiation dose to the normal tissue area surrounding the tumor is discussed