Obtaining a surface image captured by an endoscope inserted in a tubular organ associated with a surrounding blood vessel and representing an inner surface of a wall of the organ, generating, from a three-dimensional image representing a three-dimensional area including the organ, an adjacent blood vessel image depicting a portion of the blood vessel adjacent to the wall from a viewpoint in the three-dimensional image corresponding the viewpoint of the surface image, generating, from a three-dimensional image representing a three-dimensional area including a surrounding area of the organ, a surrounding blood vessel image depicting the blood vessel from a viewpoint in the three-dimensional image corresponding the viewpoint of the surface image, and causing the surface image, adjacent blood vessel image, and surrounding blood vessel image to be displayed in this order on a display unit.
