Radiological features in paediatric primary gastric MALT lymphoma and association with Helicobacter pylori

Primary malignant tumours of the stomach are very rare in children, most being lymphomas and sarcomas. The majority of primary gastric lymphomas are high-grade non-Hodgkin's lymphomas and are of B-cell origin. However, a significant number are low-grade B-cell lymphomas that are derived from mucosa-associated lymphoid tissue (MALT) that is not found in the normal stomach. Helicobacter pylori infection predisposes to the development of MALT in the stomach and provides the pathogenic background for MALT-type lymphomagenesis. To our knowledge, only eight paediatric cases of primary gastric lymphoma have been described. The diagnosis and follow-up of gastric lymphoma are mainly made by endoscopy. Nevertheless, radiologists must be aware of this disease because it may be observed on radiological examinations that are performed for nonspecific upper digestive symptoms in children.