Primary gastric lymphoma accounts for about 2% of gastric neoplasms. The prognosis of patients affected with non-Hodgkin's gastric lymphoma appears better than for other lymphatic sites. In a retrospective study, the authors have analyzed 45 patients, by evaluating the histopathologic characteristics and relative prognostic factors. The main factors significantly influencing 5-yr survival are: serosal penetration (31.17% vs. 71.2%, P less than 0.05), regional lymph node involvement (53.07% vs. 68%), and clinical stage of disease (IE: 85.6%, IVE:10%, P less than 0.001). The histologic characteristics, the high or low grade of malignancy, and patient age can also be considered important prognostic factors, but not statistically significant in our series of cases. Comparison between overall survival and disease-free survival of patients in stages IE and IIE who underwent surgery alone, with those who had chemotherapy and/or radiotherapy after surgery shows a higher survival (85.6%) of the group who had combined treatments, even though this difference is not statistically significant.