gastric diffuse large B-cell lymphoma (MONDO_0006223, a Monarch Disease Ontology entry) is an extranodal diffuse large B-cell lymphoma that arises from the stomach with the bulk of the mass located in the stomach. Also known as: primary diffuse large B-cell gastric lymphoma, primary diffuse large B-cell lymphoma of stomach, primary diffuse large B-cell lymphoma of the stomach, primary gastric diffuse large B-cell lymphoma.