A Large Colonic Intraluminal Mass in a Young Man With Chronic Diarrhea

History A 22-year-old man with a 12-year history of intermittent abdominal pain and diarrhea had an exacerbation of the diarrhea and weight loss. Representative roentgenograms of an air-contrast barium enema examination (Figs 1 and 2) are illustrated. A single-contrast barium enema study performed five years earlier had shown similar findings.