Minute nonpolypoid adenomas of the colon depicted with barium enema examination.

To evaluate the usefulness of barium enema examination for detection of small nonpolypoid adenomas, the barium enema study findings were reviewed in patients with flat or depressed adenomas of the colon 3-5 mm in diameter that had been initially found during colonoscopy and that had been diagnosed as adenomas at histologic analysis. Eleven of the 21 nonpolypoid adenomas were depicted on radiographs; they tended to be located on the left side of the colon. The 10 other lesions were not detected retrospectively on barium enema radiographs. The radiographic findings in the depicted lesions included smooth, round, radiolucent areas; in seven of these lesions, round or irregular barium flecks were also seen. The radiolucent areas were attributed either to slightly elevated growth of adenomas or to surrounding hyperplasia of nonneoplastic glands; the central barium fleck seemed to conform to depressed areas within adenomas. Barium enema examination can demonstrate nonpolypoid adenomas of the colon, even though colonoscopy seems superior to barium enema examination for detection of these lesions.