Ocular adnexal lymphoma and Helicobacter pylori gastric infection

Purpose There is a causal association between Helicobacter pylori (Hp) gastric infection and the development of gastric MALT lymphoma. In contrast, the link between Hp gastric infection and the development of extra-gastric lymphoma has not been thoroughly investigated. We therefore studied the prevalence of gastric Hp infection at initial diagnosis of ophthalmologic and non-ophthalmologic extra-gastric lymphoma patients. Methods Three cohorts of patients were studied: a first one of 83 patients with OAL, a second one of 101 patients with extra-ophthalmologic extra-gastric lymphoma, and a third one of 156 control individuals (control) without malignant lymphoma. Gastric Hp infection was investigated by histopathological analysis and Hp-specific PCR assay on gastric biopsy tissue samples. Results We found gastric Hp infection in 37 OAL patients (45%), in 25 extra-ophthalmologic extra-gastric lymphoma cases (25%), and in 18 controls individuals (12%) (p<0.0001 OAL/C and p<0.01 OAL/extra-OAL cases). Gastritis was found in 51% and 9% of Hp-positive and Hp-negative lymphoma patients, respectively (p<10-4). Gastric Hp infection only correlated with MALT/LPL lymphoma (p = 0.03). Conclusion There is a significant association between gastric Hp infection and MALT/LPL OAL. This suggests a novel mechanism of indirect infection-associated lymphomagenesis whereby chronic local antigen stimulation would lead to the emergence of ectopic B-cell lymphoma.