1. A system for processing a breast image, comprising: a glandular tissue contour detector that detects a contour of a glandular tissue represented in the breast image, the glandular tissue contour detector cornprising a concave hull determiner that determines a concave hull of a region in the breast image comprising the mammary glands of a breast so as to obtain the contour; and a display unit that displays the breast image with the contour superimposed.