Early, Isolated Duodenal Mucosa-Associated Lymphoid Tissue Lymphoma Presenting without Symptoms or Grossly Apparent Endoscopic Lesions and Diagnosed by Random Duodenal Biopsies

Abstract

Clinical data regarding mucosa-associated lymphoid tissue lymphoma (MALToma) solely involving the duodenum are sparse because of the relative rarity of the disease. A comprehensive literature review revealed only 17 cases reported until 2004, and only a moderate number of cases have been reported since. MALToma can be asymptomatic in its very early stages but frequently produces localized or nonspecific symptoms, including early satiety, abdominal pain, vomiting, and involuntary weight loss in later stages. While gastric MALToma is strongly associated with gastric Helicobactor pylori infection, duodenal MALToma is often unassociated with H. pylori infection. A 74-year-old female presented with only dysphagia (without symptoms referable to a duodenal lesion), without systemic 'B' symptoms, and with no evident duodenal lesions at esophagogastroduodenoscopy; however, she was diagnosed with duodenal MALToma by pathologic examination of random duodenal biopsies performed to exclude celiac disease. An important clinical feature of this case is that duodenal MALToma was diagnosed by pathologic analysis of duodenal biopsies despite (1) no endoscopically apparent duodenal lesions; (2) duodenal involvement without gastric involvement; (3) lack of symptoms attributable to duodenal MALToma, and (4) absence of evident H. pylori infection. This work shows that early duodenal MALToma can be difficult to diagnose because of absent symptoms, absence of gastric involvement, absence of endoscopic abnormalities, and absence of H. pylori infection; it may require random duodenal biopsies for diagnosis.

Keywords: Duodenum; Esophagogastroduodenoscopy; Helicobacter pylori; Lymphoma; Mucosa-associated lymphoid tissue lymphoma.

Fig. 1

Endoscopic appearance of the descending duodenum in a 74-year-old female showing retained, partially digested food in a small part of the descending duodenum, and no evident endoscopic abnormalities in the remaining 80% of the descending duodenum. Pathologic examination of endoscopic biopsies of normal appearing mucosa of the descending duodenum revealed MALToma.

Fig. 2

Histopathologic examination of endoscopic biopsies of the descending duodenum in a 74-year-old woman with no evident endoscopic duodenal lesions. a Low-power photomicrograph from a duodenal biopsy showing a dense infiltrate of small mature lymphocytes extensively involving the submucosa, with otherwise unremarkable duodenal mucosa (H&E, ×10). b High-power photomicrograph from a duodenal biopsy showing a monotonous proliferation of small mature lymphocytes, with some evident monocytoid differentiation (H&E, ×40). c Immunohistochemistry for the B-cell marker CD79a shows strong positivity in most cells of the lymphocytic infiltrate, highly consistent with the diagnosis of a B-cell lymphoma (×40). d Normal tonsil, used as an external control, demonstrates positive staining with CD79a on the left in a lymphoid follicle and absent staining with CD79a on the right in an adjacent area containing T cells.