Helicobacter pylori infection in gastric extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma: a re-evaluation

In 1991 Wotherspoon et al 1 showed a close association between Helicobacter pylori infection and gastric mucosa-associated lymphoid tissue (MALT) lymphoma (GML) with the organism present in 92% of cases. Other studies have shown this association to be varying between 42% and 100%. In vitro studies at that time showed that lymphoma cell proliferation was associated with the presence of H. pylori mediated through specific tumour infiltrating T cells in a contact dependant manner. In the light of this finding Wotherspoon et al 1 were able to demonstrate that eradication of H. pylori induced lymphoma regression. In a recent Gut article, Nakamura et al 2 demonstrated that H. pylori eradication therapy can result in durable lymphoma regression in the majority of cases. However, absence of H. pylori infection is a known predictive factor for eradication resistance.3 Prevalence of H. pylori has shown signs of decrease especially among Western populations. A decline in the number of GML H. pylori -positive has also been reported.4–7 To address these issues, we performed a retrospective review to analyse the H. pylori infection status …