Table 6.

Association with Helicobacter pylori infection and gastrointestinal tract lymphoma

	Prevalence of H. pylori	Diagnostic tool for H. pylori	Study design	P value
Parsonnet et al[95] (Gastric NHL)	OR: 6.3; 95%CI: 2.0-19.9	Serology	Case- control study	NA
Ishikura et al[97] (Gastric lymphoma overall)	OR: 2.14; 95%CI: 1.3-3.5	Serology	Case- control study	P = 0.003
Ishikura et al[97] (Gastric MALT)	OR: 1.96; 95%CI: 1.0-3.9	Serology	Case- control study	P = 0.051
Ishikura et al[97] (Gastric DLBCL)	OR: 1.92; 95%CI: 0.74-4.95	Serology	Case- control study	P = 0.178
Parsonnet et al[95] (Non-gastric NHL)	OR: 1.2; 95%CI: 0.5-3.0	Serology	Case- control study	NA

NHL: Non-Hodgkin’s lymphomas; MALT: Mucosa-associated lymphoid tissue; DLBCL: Diffuse large B-cell lymphoma; OR: Odds ratio; CI: Confidence interval; H. pylori: Helicobacter pylori; NA: Not available.