1. An image processing apparatus comprising at least one processor and memory coupled to each other and cooperating to act as: a first image obtaining unit configured to obtain a first medical image of an object in a first shape state; an imaging region setting unit configured to set a region to be imaged of the object in a second shape state, before taking a second medical image of the object in the second shape state; a deformation information obtaining unit configured to obtain deformation information indicating deformation of the object from the second shape state to the first shape state; a corresponding region calculating unit configured to calculate a corresponding region that corresponds to the region to be imaged in the first shape state based on the deformation information; a display control unit configured to cause a display unit to display the first medical image and the corresponding region; and an imaging region outputting unit configured to output information of the region to be imaged to a medical imaging apparatus in order to take the second medical image by using the medical imaging apparatus based on the information of the region to be imaged.