Table 1.

Histologic scoring system for the diagnosis of gastric MALT lymphoma (Wotherspoon score) [4].

Grade	Description	Histologic Features
0	Normal	Scattered plasma cells in mucosa; no lymphoid follicles.
1	Chronic active gastritis	Small clusters of lymphocytes in mucosa; no lymphoid follicles; no lymphoepithelial lesions.
2	Chronic active gastritis with florid lymphoid follicle formation	Prominent lymphoid follicles with surrounding mantle zone and plasma cells; no lymphoepithelial lesions.
3	Suspicious lymphoid infiltrate in mucosa, probably reactive	Lymphoid follicles surrounded by small lymphocytes that have infiltrated diffusely in the mucosa and occasionally into epithelium.
4	Suspicious lymphoid infiltrate in mucosa, probably lymphoma	Lymphoid follicles surrounded by centrocyte-like cells that have infiltrated diffusely in the mucosa and epithelium in small groups.
5	MALT lymphoma	Presence of dense diffuse infiltrate of centrocyte-like cells in the mucosa with prominent lymphoepithelial lesions.