Gastric lymphoma: the revolution of the past decade.
BACKGROUND
Gastric MALT type lymphomas are distinct lymphomas that may develop after chronic antigenic stimulation caused by infection with Helicobacter pylori. An early antigen-dependent phase precedes the development of an antigen-independent phase.


METHODS
Narrative review.


RESULTS
The causative relationship between a chronic H. pylori infection and gastric MALT lymphomas has been based on epidemiological, histological, experimental and therapeutic studies. H. pylori eradication leads to a histological remission in +/- 70% of patients in early stage low-grade MALT lymphoma. There is no basis for therapeutic consequences in the case of persistent monoclonality. Full thickness invasion of the gastric wall and lymph node involvement and/or high-grade lymphoma denote the transition to an antigen-independent phase and calls for conventional treatment modalities. Molecular findings show a specific translocation in low-grade MALT lymphomas: t(11,18) and nuclear expression of bcl-10 that are highly indicative of the transition of the antigen-dependent into the antigen-independent phase. Other chromosomal and molecular findings are probably also involved.


CONCLUSIONS
The multistep pathogenesis of chronic H. pylori gastritis into low-grade gastric MALT lymphoma and tumour progression to a higher stage and grade are characterized by multiple molecular biological events. Antigen-dependency during the early phase of this malignancy is proven by the results of H. pylori eradication.
Boot
H
H
Dept. of Gastroenterology, Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Amsterdam. h.boot@nki.nl
de Jong
D
D
D002908:Chronic Disease; D005753:Gastric Mucosa / Q000276:immunology / Q000473:pathology; D005756:Gastritis / Q000150:complications / Q000276:immunology / Q000628:therapy; D005773:Gastroscopy; D016481:Helicobacter Infections / Q000150:complications / Q000276:immunology / Q000628:therapy; D016480:Helicobacter pylori; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000209:etiology / Q000276:immunology / Q000628:therapy; D009367:Neoplasm Staging; D013274:Stomach Neoplasms / Q000209:etiology / Q000276:immunology / Q000628:therapy