Primary gastrointestinal lymphoma in childhood (up to 18 years of age). A morphological, immunohistochemical and clinical study.

A group of 47 patients up to 18 years of age, with primary non-Hodgkin's lymphoma of the gastrointestinal tract, were investigated. The lesions were located in the stomach (n = 2), small intestine (n = 17), the ileocecal region (n = 20), the large intestine (n = 7), and multifocally in the small and large intestines (n = 1). Of the patients, 41 were male and 6 were female; their age at presentation ranged from 2 to 18 years. All of the cases belonged to the high-grade malignancy group of the updated Kiel classification. Burkitt's lymphoma was the most frequent histological type (n = 35), followed by centroblastic lymphoma (n = 3), immunoblastic lymphoma (n = 2), lymphoblastic lymphoma (n = 1), and large-cell anaplastic lymphoma (n = 1). Five of the patients had high-grade unclassified B-cell lymphoma. Of all the lymphoma types 41 cases (87%) were positive for Ki-B3 (a B-cell marker). Expression of monoclonal immunoglobulin was demonstrated in 8 of 35 cases (23%) of Burkitt's lymphoma, in all 3 cases of centroblastic lymphoma, in both cases of immunoblastic lymphoma, in the single case of lymphoblastic lymphoma, and in all 5 cases of high-grade unclassified B-cell non-Hodgkins lymphoma. Most of the Burkitt's lymphomas showed the light chain lambda (7/8). According to the staging classification of Murphy (N Engl J Med 299:1446-1448, 1978), 12% of the 34 cases available were stage IE, 44% stage IIE, 38% stage IIIE, and 6% stage IVE. Of these 34 patients, 13 died with lymphoma within 1 year after diagnosis. The survival rate for the 19 patients in stages I and IIE at 2 years was 83%, while for the 15 patients in stages III and IVE it was 32% (P less than 0.05). A significant difference in survival was found between the 13 patients with primary involvement of the small intestine and the 20 patients with primary involvement of the large intestine and ileocecal region, the latter showing a better prognosis. Lymphoma type did not significantly influence survival. Our findings indicate that the stage at diagnosis and the primary site are important prognostic features in gastrointestinal non-Hodgkin's lymphoma.