Malignant lymphoma of the colon rectum: roentgen diagnosis.

The filling defects of a particular lymphosarcoma of the colon or rectum may present an appearance identical to that of a carcinoma in the same location. In general, lymphosarcomas tend to be longer, more distensible, less sharply demarcated, more frequently polypoid, and to feel larger as palpable masses. The filling defects are infrequently of the annular "napkin ring" appearance, and occasionally the involved segment is dilated.