Editing Gastric lymphoma (section)

== '''Pathophysiology''' ==

* Diffuse large B cell lymphoma     - '''DLBCL''' (45-60%)
** Generally primary lesions,      but can also occur as progression from less aggressive lymphomas such      CLL, small lymphocytic lymphoma, follicular lymphoma, or MALT lymphoma
** Associated with      immunodeficiency and H. pylori infection
** Fairly high-grade
* Gastric Mucosa-Associated     Lymphoid Tissue ('''MALT''') lymphoma (40-50%)
** Lower grade than DLBCL
** B cell lineage
** Usually preceded by H.      pylori gastritis (in almost all cases). B cells are chronically activated      in stomach, forming a MALToma, which can transform into lymphoma.
** Characterised by      translocations at:
*** T(1;14)
*** T(3;14)
*** T(11;18)
*** T(14;18)
* Peripheral T cell lymphoma     (1-4%)
* Mantle cell lymphoma (<1%)
* Follicular lymphoma (<1%)
* Usually occurs in gastric     antrum, but can arise from anywhere