Molecular subtyping of gastric MALT lymphomas: implications for prognosis and management

ince mucosa associated lymphoid tissue (MALT) lymphomas were first recognised as a distinct entity in 1983, their characterisation and management have seen a series of rapid advances. Here we concentrate on MALT lymphomas at the commonest site-the stomach. Historically, despite their indolence, ''localised'' gastric low grade lymphomas were treated with surgery, and chemotherapy or radiotherapy were reserved for systemic spread. This emphasis has gradually changed but the major advance came with the discovery that these tumours were caused by Helicobacter pylori infection, and the remarkable finding that most resolved with its treatment. 1 H pylori eradication quickly became a firstline therapy, and the research focus changed to how best to assess which cases would respond to this. Endoscopic ultrasound became important for staging and, to some extent, stage predicted response to H pylori eradication. However, the most exciting research over the past eight years has been in understanding the molecular genetics of these fascinating tumours. In this review, we describe these advances and discuss their implications for management, particularly the extent to which they predict the biological behaviour and response of the tumour to H pylori treatment.