In a console, a control unit functions as an acquisition unit that acquires a radiographic image of a breast, a derivation unit that derives a mammary gland content rate for each pixel of a breast region in the radiographic image, and a detection unit that detects a mammary gland concentrated region in which mammary glands are concentrated on the basis of a result of specifying whether a specific pixel which is each pixel of the breast region is a pixel included in the mammary gland concentrated region of the breast region on the basis of the mammary gland content rate of the specific pixel and a mammary gland content rate of a pixel in a local region around the specific pixel.
