The authors present the case of a 33-year-old female patient with dyspepsia. An esophagogastroduodenoscopy was performed (fig. 1). In the second portion of the duodenum (D2), a 15 mm bulge with normal mucosa, non-pulsatile, soft consistency, without pillow sign was observed.
Figure 1. Esophagogastroduodenoscopy (D2): a non-pulsatile 15 mm bulge with normal mucosa and soft consistency.
Endoscopic ultrasonography (EUS) revealed a well-defined hypoechoic nodule arising from the second layer of the duodenal wall, measuring 11 x 4 mm (fig. 2). The nodule echotexture was homogenous, with no calcifications or lymphadenopathies.
Figure 2. Radial EUS (D2): a well-defined hypoechoic homogeneous nodule arising from the second layer of the duodenal wall, measuring 11 x 4 mm.
These findings were compatible with Brunner’s gland hyperplasia. An endoscopic mucosal resection was performed. Histopathological analysis revealed cystic Brunner glands, with no dysplasia or neoplasia. A final diagnosis of Brunner’s gland hyperplasia was made.
Brunner’s gland hyperplasia (BGH), also referred in the literature as Brunner’s gland adenoma and hamartoma, consists of a hyperplastic proliferation of mature Brunner’s glands [1,2]. These are acinotubular exocrine glands located in the submucosal layer of the duodenum that secrete mucin, an alkaline fluid that protects the duodenum from gastric acidity [2]. BGH is a rare lesion, comprising less than 1% of gastrointestinal neoplasms [1]. They usually present as an incidental finding, however occasionally they may be large in size and cause obstruction or bleeding [2,3,4].
Endoscopically BGH may present as a polyp or subepithelial lesion, and the ultrasonographic findings are variable: located mainly in the submucosal layer or extended to the mucosal layer (third and second EUS layers, respectively); variable echogenicity; solid, large, or small cystic; round and well-circumscribed [5]. Although it has generally been considered a benign lesion, there are a few cases reported in the literature where dysplasia and malignant transformation occurred, and therefore endoscopic resection can allow for diagnosis and exclude malignancy [2,6].
Diogo Bernardo Moura1, Nuno Nunes, Carolina Chálim Rebelo1, Francisca Côrte-Real1, Maria Antónia Duarte1.