1. A medical image processing apparatus comprising: an image data generator which generates image data corresponding to at least two different energy bands using an X-ray; a region of interest (ROI) processor which highlights tissue of interest classified based on a predetermined characteristic to be distinguished from a normal tissue in the generated image data; and a display which alternately displays first image data in which the tissue of interest is not highlighted, and second image data in which the tissue of interest is highlighted to be distinguished from the normal tissue.