Cancer and its treatments induce important physical transformations, which could be source of psychological and social difficulties. Since about 15 years, interest for cancer and treatments consequences on body image had grown in oncology. Nevertheless studying body image remains complex because of conceptual and methodological limits. This article aims at a clarification about the methods employed in the field of cancer to assess body image, in order to make accessible reference marks about adapted instruments for every person who would like to study this theme.