[Adenoma of Brunner's glands]. / Adenoma de las glándulas de Brunner.

Brunner's glands adenomas represent the 10% of the benign duodenal tumours. The most frequent site is the first portion of the duodenum, and they are extremely rare distally to the ampulla of Vater. We present two cases, one of them associated with an adenocarcinoma of the ampulla. This association has not been previously described in the literature. The transformation of an adenoma into an adenocarcinoma has neither been reported. We believe that the term hyperplasia should be used only for diffuse proliferations.