However, we do know individual genetics, other medical problems, use of certain medications, smoking, and the genetic diversity of Helicobacter strains all play a role.
This type is extranodal - mostly happening in the lining of the stomach among individuals with chronic inflammation, like those with Helicobacter pylori infection, a bacteria that causes chronic gastritis.
The process of discovery began in 1983 when Barry Marshall, a doctor in Perth, Western Australia, found that many stomach cancers and most stomach ulcers are caused by a bacterium called Helicobacter pylori.
Helicobacter is a genus of Gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the Campylobacter genus, but in 1989, Goodwin et al. published sufficient reasons to justify the new genus name Helicobacter. The Helicobacter genus contains about 35 species.