We reported a case of duodenal carcinoid evaluated by ultrasonic probe (USP) . A 59-year-old man was admitted to our hospital in May 1994 with epigastralgia. A filling defect was detected on routine upper gastrointentestinal X-ray examination, and endoscopic finding showed a small elevated lesion on the anterior wall of the duodenal bulb. Biopsy revealed typical features of carcinoid tumor. USP revealed a hypoechoic tumor with regular margin in the 2nd-3rd layer of the wall. The tumor, measuring 7×8mm in size, was removed by surgical operation. The tumor was located in the duodenal submucosa. USP with miniature probe was thought to be useful for the diagnosis of the extent and depth of invasion of a small duodenal carcinoid tumor.
