The cases of 42 consecutive patients with primary gastrointestinal lymphoma were reviewed to compare the risks and outcomes of different primary treatment modalities. Among patients with localized disease (stages I and II), 12 underwent complete tumor resection and 6 underwent radiation therapy; 5-year survival was 82% and 50%, respectively. Among patients with disseminated disease (stages III and IV), 6 underwent resection of the primary tumor followed by chemotherapy and 18 were treated with radiation and chemotherapy; 5-year survival was 81% and 6%, respectively. Five patients who did not undergo surgical resection before radiation therapy or chemotherapy developed severe life-threatening complications from their primary tumor. Surgical resection before the administration of other therapy should be performed when the patient is considered to be a surgical candidate and resection of the primary tumor is deemed feasible.