A true Brunner’s gland adenoma

Brunner’s gland adenoma is an extremely rare neoplasm, which may be confused with Brunner’s gland hyperplasia or hamartoma. The present report describes a case of “true” Brunner’s gland adenoma resected by surgery.

An 82-year-old man with a duodenal polyp was admitted to hospital for surgical treatment of newly diagnosed gastric cancer. Gastroduodenoscopy revealed a 12-mm subpedunculated polypoid lesion, covered with smooth, reddish mucosa, in the duodenal bulb (Figure [1]). Distal gastrectomy was carried out for the gastric cancer and for the duodenal polypoid lesion.

Figure 1 The duodenal polypoid lesion at chromoendoscopy.

Histologically, the duodenal polypoid lesion was found to consist of Brunner-like glands with moderate nuclear atypia. Nonneoplastic Brunner’s gland hyperplasia was seen at the basal side of the polypoid lesion (Figure [2]). Figure [2 ] b shows the transition from the hyperplastic area to the adenomatous area. Immunohistochemically, the adenomatous Brunner-like glands were positive for MUC6, showing that they originated from Brunner’s glands. The surface of the polypoid lesion was covered with gastric foveolar-like glands.

Figure 2 a, b The histological appearance of the polypoid lesion, showing the transition from the Brunner’s gland hyperplastic area to the adenomatous area. a Hematoxylin-eosin, original magnification × 30. b Hematoxylin-eosin, original magnification × 50.

Brunner’s gland adenoma is extremely rare, representing only 10.6 % of benign duodenal tumors [1], which are themselves rare at 0.008 % of all surgical and autopsy specimens. Matsumoto et al. reported a case of a large Brunner’s gland adenoma removed by endoscopic polypectomy [2]. Fujimaki et al. reported a case of duodenal polypoid lesion consisting mainly of hyperplastic Brunner’s glands, but with a focus of atypical glands consisting of cells with nuclear atypia [3]. There have been reports of neoplasia occurring in Brunner’s gland hyperplasia [4]. The present case shows a transition from a hyperplastic area in the Brunner’s glands to an adenomatous area, showing that a “true” Brunner’s gland adenoma can exist and suggesting its etiology.

Endoscopy_UCTN_Code_CCL_1AB_2AZ_3AB

References

• 1 Nakanishi T, Takeuchi T, Hara K, Sugimoto A. A great Brunner’s gland adenoma of the duodenal bulb.  Dig Dis Sci. 1984;  29 81-85
• 2 Matsumoto T, Iida M, Matsui T. et al . A large Brunner’s gland adenoma removed by endoscopic polypectomy.  Endoscopy. 1990;  22 192-193
• 3 Fujimaki E, Nakamura S, Sugai T, Takeda Y. Brunner’s gland adenoma with a focus of p53-positive atypical glands.  J Gastroenterol. 2000;  35 155-158
• 4 Doi K, Tada S, Fujimoto T. et al . Successful endoscopic removal of a duodenal adenoma occurring in Brunner’s gland hyperplasia.  Dig Endosc. 2004;  16 148-151