Primary gastric lymphoma. An analysis with emphasis on prognostic factors and radiation therapy.

Primary gastric lymphoma, lymphoma originating in the stomach, without involvement of peripheral or mediastinal lymph nodes, viscera, or the bloodstream, is sufficiently uncommon that the indications for radiation therapy, the dose of irradiation necessary for control of lymphoma, optimum field size, and patterns of failure have never been established. The authors identified 26 patients, and reviewed their charts and pathologic material. Their overall 5-year survival was 57%. Factors significantly influencing 5-year survival were serosal penetration (32% versus 91%), regional lymph node involvement (33% versus 81%), and location on the lesser curvature (20% versus 89%). Histologic characteristics, extent of surgery, and, provided the patient was irradiated, involvement of surgical margins did not influence survival. Overall, survival was not affected by irradiation, but in patients with poor prognostic factors there appeared to be a beneficial effect. Analysis of local control in this and other series suggests that patients should receive at least 40 Gy, and that whole abdominal irradiation is not necessary. The majority of failures were distant, indicating a need for effective systemic therapy.