A 63-year-old woman came to our hospital complaining of recurrent upper abdominal fullness discomfort for almost 10 years. She experienced exacerbation of intermittent nausea, vomiting with chyme (5 mL), heartburn, acid regurgitation, and eructation for 6 months. No history of hypertension, diabetes mellitus, or coronary heart disease was noted. Upon physical examination, a 5 x 4 cm mass with a hard texture and poor mobility was observed in the upper abdomen. Routine blood and tumor marker test results were within normal range. Abdomen computed tomography (CT, Figure 1A) showed a 32 mm x 22 mm soft tissue mass shadow with homogeneous density in the descending duodenum, which was protruding into the duodenal lumen. Moreover, thickening of the adjacent intestinal wall was noted. Upper abdomen magnetic resonance imaging (MRI, Figure 1B) revealed a significant thickening of the wall of the duodenal bulb and descending duodenum. The wall thickness was 1.1 cm. The signals were slightly low in T 1-weighted images and slightly high in T 2-weighted images. Endoscopic ultrasonography (Figure 1C and D) demonstrated that there was a protrusion in the duodenal bulb of about 26 x 18 mm in size with a clear boundary, smooth surface, and irregular shape and the base being about 17 mm, color signals abound.
Neoplasm resection of duodenum was performed, and we found a mass measuring about 25 x 30 x 10 mm located in the descending duodenum. It was soft, brittle, and mobile with a clear boundary. The pathological result (Figure 2) of the mass revealed multiple Brunner's glands with tubes, fibers, and smooth muscle diffuse distribution. No dysplasia was noted on the epithelium. It was diagnosed as Brunner's gland adenoma of the duodenum. The patient was discharged from the hospital a week after recovery. To date, no relapse has occurred.