Localized primary gastric amyloidosis: Three case reports

Abstract

Background: Localized primary gastric amyloidosis is a rare disorder characterized by the extracellular deposition of insoluble fibrillary protein in the stomach and can mimic various diseases on endoscopic examination, including gastrointestinal stromal tumors, gastric cancer and ulcers.

Case summaries: Here, we report a series of three cases of localized gastric amyloidosis mimicking gastric mucosa-associated lymphoid tissue (MALT) lymphoma on endoscopic examination that were evaluated over the past ten years in our hospital. The different detection times of this rare disease resulted in three completely different outcomes, indicating the strong importance of early detection, diagnosis and treatment. The difficulties encountered in making an accurate diagnosis and differential diagnosis are highlighted, and this report provides clinical experience for the diagnosis of localized primary gastric amyloidosis.

Conclusion: Localized gastric amyloidosis is a rare metabolic disease that resembles MALT lymphoma. Early detection, diagnosis and treatment of localized gastric amyloidosis result in an excellent prognosis.

Keywords: A case series study; Case report; Different outcomes; Localized gastric amyloidosis; Mucosa-associated lymphoid tissue lymphoma; Rare disease.

Figure 1

Endoscopic and histological data of patient 1. A: Esophagogastroduodenoscopy revealed a faint reddish flat elevated lesion, 15 × 16 mm in size, with multiple nodules on the surface in the great curvature of the antrum adjacent to the corpus. B: Narrow-band imaging (NBI) indicated a defined green area. C: Magnifying endoscopy with NBI showed expanded normal glands with changed polarity as well as dilated and tortuous vessels. D: Hematoxylin-eosin staining showed cystic dilated gastric glands. E: Massive and cord-like pink substances were deposited in the mesenchyme and inside the blood vessel wall at the bottom of the lamina propria mucosa, muscularis mucosae and superficial submucosal layer. F: Polarized light microscopy revealed apple-green birefringence in the lesions. Orange arrows indicate amyloid depositions.

Figure 2

Endoscopic and histological data of patient 2. A: Conventional endoscopy showed a red and white area in the atrophic gastric antrum with active gastritis. B: Narrow-band imaging (NBI) showed a defined light brownish area. C: Magnifying endoscopy with NBI revealed expanded normal glands with changed polarity and tree-like vessels. D: Hematoxylin-eosin staining showed abundant cord-like red substances in the mucosal layers. E: These tissues were positive for Congo red staining. Orange arrows indicate amyloid depositions.

Figure 3

Endoscopic and histological data of patient 3. A: Conventional endoscopy demonstrated that the whole gastric mucosa was congestive, edematous and mainly red. B: Endoscopic ultrasound showed that the mucosa and submucosa layer were thickened (white arrow) but that the muscle and serosal layers were intact. C: A gastric tube was placed into the antrum to provide nutritional support. D: Hematoxylin-eosin staining revealed an abundant brick-red substance in the mucosal and submucosal layers. E: These tissues were positive for Congo red staining. Orange arrows indicate amyloid depositions.