Antisecretory medication is associated with decreased Helicobacter pylori detection in gastric marginal zone lymphoma.

ABSTRACT

Helicobacter pylori status influences the prognosis and management of gastric extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), so accurate determination of H pylori status is of clinical importance. The low rate of histologic H pylori positivity among gastric MALT lymphoma cases at our institution prompted investigation for possible causes. A case series of 24 patients as having gastric MALT lymphoma (with no diffuse large B-cell component) in a tertiary care setting between 1997 and 2010 was identified, and clinical records were reviewed. Immunohistochemical staining for H pylori and BCL10 was performed. This study received institutional review board approval (protocol number M13-033). Thirty-nine percent of cases (9/23) were H pylori positive by histology, and 4 additional patients had positive serologic results; overall, 57% of cases (13/23) were positive for H pylori. Treatment with antisecretory medications was associated with a lower likelihood of histologic positivity (13% among treated patients vs 75% among untreated; P = .04). Nuclear localization of BCL10 was seen in 2 cases and was not associated with H pylori status. Antisecretory medications decrease the likelihood of histologic detection of H pylori in gastric MALT lymphoma cases. Incorporation of results of serologic or other testing is needed to ensure correct classification with respect to H pylori status.