Apparatus and method for generating printing data for patient-specific applicator, and system for manufacturing patient-specific applicator

In a system for manufacturing a patient-specific applicator, a three-dimensional (3D) image is reconstructed using patient medical images, the structure of an applicator for emitting radiation at tumor tissues is modeled on the basis of the 3D image, printing data for 3D printing for manufacturing a patient-specific applicator on the basis of the modeled structure of the applicator is generated, and the patient-specific applicator is manufactured on the basis of the generated printing data.