A system that assists in treatment includes circuitry configured to generate three-dimensional body data of a patient using data obtained from a three-dimensional measurement unit, obtain a tomographic image of the patient from a body tomographic measurement apparatus, execute an examination assist process, which aligns the three-dimensional body data with the tomographic image, execute a treatment plan assist process, which make a treatment plan that specifies a posture of the patient when treatment is performed using the tomographic image and the three-dimensional body data that are aligned with each other, and execute a treatment assist process, which outputs a treatment instruction based on the posture specified in the treatment plan.
