Histopathological and Immunohistochemical Studies of Primary Gastrointestinal Lymphomas in Korean Patients

ABSTRACT

The present study is aimed to investigate the clinical and pathologic features of GI lymphomas and the immunocytochemical characteristics, using 71 cases of primary GI lymphomas examined at the Department of Pathology, Yonsei University College of Medicine, Youngdong Serverance Hospital and Yonsei University Wonju College of Medicine from January, 1976 to December, 1985. Results obtained were as follows 1) Sixty eight cases were Non-Hodgkin's lymphoma and 3 Hodgkin's lymphoma. Surgical resection was done in 58 patients and surgical biopsy in 13. 2) The primary sites of the tumors were stomach, small intestine, ileocecal area and large intestine in a descending order of frequency. 3) The mean age at the time of diagnosis was 45 years. The tumor of the small intestine was generally detected in the younger age and that of the large intestine in the older age. The overall male to female ratio was 1.9 1. 4) Abdominal pain was the most common presenting symptom irrespective of the sites of the tumor. Duration of the symptoms were evenly distributed from hours to 12 monthes. 5) The size of the tumors was less than 10 cm in the largest dimension in most of the cases (79.3%). The gross types of the GI lymphomas were ulcerative (27.6%), polypoid (20.7%), multinodulated (17.2%) and diffuse thickening. The rate of lymph node involvement was 44.4% in tumors confined to the serosa, while 82.6% in tumors with serosal penetrations. 6) Classification of 68 cases of Non-Hodgkin's lymphoma according to Working Formulation revealed 50 cases of intermediate grade, 13 cases of high grade and 5 cases of low grade. According to Rappaport classification, all were diffuse types, among which diffuse histiocytic type was the most common. According to Lukes-Collins classification, 60 cases were B cell types, 4 cases genuine histiocytes types and 3 cases T cell types. Most of the gastric and intestinal lymphomas belonged to the follicular center cell (small and large cleaved, large cleaved) types. 7) Immunoperoxidase stains were done in 55 cases of malignant lymphomas. Thirty (65.9%) of 47 B cell lymphomas revealed a positivity for B cell markers. Twenty three (48.9%) of them showed a monoclonality, in which kappa/IgG pattern was most frequently demonstrated. Four cases of true histiocytic lymphomas were positive for alpha-1-antichymotrypsin and lysozyme, the former of which was seemed to be a more sensitive marker for histiocytic differentiation. An attempt was made to evaluate the significance of the degree of reactive histiocytic infiltrates within the lymphoma in relation to the progosis, but correlation could not be made because of the limited cases.