Gastric diffuse large B-cell lymphoma cured with Helicobacter pylori eradication regardless of whether it contains features of MALT lymphoma.

A 66-year-old patient was diagnosed with primary gastric B-cell lymphoma. The pathological findings were consistent with diffuse large B-cell lymphoma (DLBCL); however, a small area showed features of mucosa-associated lymphoid tissue (MALT) lymphoma. Biopsy specimens were referred to two other pathologists, both of whom diagnosed the case as pure DLBCL, denying the area of MALT lymphoma. As the lymphoma was limited to the submucosal layer and the patient's general condition was excellent, eradication of Helicobacter pylori was selected as the initial treatment. The lymphoma completely disappeared three months after the eradication treatment, and complete remission has been maintained for nearly two years.