Primary gastric lymphoma. A review of 50 cases.

The records of 50 patients with localized primary gastric lymphoma were reviewed and clinical and prognostic factors characterized. Pathologic material was reclassified according to Rappaport's, Lukes-Collins, and Lennert's Kiel classifications. Factors with the greatest prognostic significance included initial stage as determined by surgery and pathology, absolute tumor size, degree of penetration through the stomach wall, and histologic grade of the lymphoma. After surgical resection for cure, the overall 5-year disease-free survival was 47%. For stage I disease, this was 78% vs 29% for stage II (P = 0.006). Patients with lymphomas less than 5 cm in diameter had 58% 5-year disease-free survival vs 32% for those with tumors greater than 10 cm (P = 0.06). Full-thickness penetration decreased 5-year survival from 75% to 38% (P = 0.06). Patients with histologically low-grade lymphomas had a better prognosis than those with high-grade lymphomas. The most significant correlation of histology to survival was seen with the Kiel classification with a 5-year survival of 39% for centroblastic polymorphous lymphoma vs 66% for LP immunocytoma. When lymphoma recurred it developed outside the abdomen in a majority of patients. The addition of abdominal radiation therapy to surgical resection made no significant impact on survival for either stage I or II disease.