What is this appearance likened to and what diagnosis does it imply?
Apple-core. Usually the result of a stenosing circumferential adenocarcinoma.
Double-contrast barium enema demonstrates a focal narrowing in the sigmoid colon. It has rolled, heaped up shoulders and results in a severe stenosis. Features are typical of the so-called apple-core stenosis. The remainder of the imaged colon appears normal in calibre, and lined by normal mucosa.