Primary gastric plasmacytoma associated with Helicobacter pylori infection: a report of two cases with different prognosis.

We describe two cases of primary gastric plasmacytoma (GP) associated with Helicobacter pylori infection. Case 1 was that of a 58-year-old man with epigastric pain. H. pylori was eradicated before surgical resection was performed, and after the therapy, the tumor size was reduced. A postoperative pathological examination revealed that the tumor was in early stage and histological grade was grade 1. After 44 months of operation, the patient was in complete remission with no evidence of local relapse or progression to systemic MM. Case 2 was that of a 70-year-old woman with a history of melena. H. pylori eradication was not presented preoperatively. The resected specimen showed the tumor was in advanced stage and histological grade 3. GP eventually progressed to MM and she died of pulmonary infection. In our opinion, GP cannot be eradicated with H. pylori eradication, but disease progression can be effectively controlled to a certain extent. The prognosis of this disease is relatively fair when treated at an early stage. In addition to the treatment, the difference in prognosis could be associated with age, the stage of the tumor, and histological grade.