Non-Hodgkin's Lymphoma in the first two decades. Morphologic and immunocytochemical study.

Abstract

The histopathologic and anatomoclinical features of 211 cases of non-Hodgkin's lymphoma (NHL) were reviewed and each case reclassified according to Lukes-Collins, Kiel and Rappaport criteria. Immunologic determination of cell phenotype in 63 cases as well as assessments of immunoglobulin and lysozyme by immunoperoxidase in 48 cases, permitted a precise definition of cell lineage on a functional basis and showed a high degree of predictability of immunologic phenotype of lymphoma cells by conventional morphology. The results of immunologic cell typing and immunoperoxidase studies were consistent with functional schema of Lukes-Collins and Kiel. “True” histiocytic proliferations, (9 cases) showed biologically different behavior from malignant lymphoma (ML), by a high incidence of extralymphatic (skin and soft tissue) presentation, rapid course, and frequent conversion to histiocytic leukemia. Fifty-two percent of studied ML cases were categorized morphologically as B-cell line proliferations, 36.7% as T-cell line and 6.9% as undefined group (ML “U” type). The ratio of T-cell to B-cell malignancies was 1∶1.4. The convoluted type lymphoma was characterized by a high incidence (70%) of anterior mediastinal presentation, high incidence (over 60%) of hematologic and CNS involvement, and a high probability of testicular relapse, especially late. In contrast to malignancies of the T-cell line, B-cell proliferations tended to be localized below the diaphragm, and the most common anatomic location of lymphoma growth appeared to be the gastrointestinal tract, where small and large noncleaved follicular center cell types predominated. The nodular lymphoid hyperplasia in the vicinity of intestinal lymphoma and lack of secretory component within enterocytes were other substantial findings in abdominal B-cell malignancies. Among immunoblastic proliferations, the B-cell type was found to predominate over T-cell and was characterized as highly aggressive disease with a relatively common marrow infiltration. A low anatomic stage of disease and a favorable outcome were closely related to small cleaved type of follicular center cell lymphoma, which comprised only 1.5% of the patients studied. The less defined and morphologically heterogeneous group formed ML “U”, which in over 95% of patients converted to acute lymphocytic leukemia. This joint analysis of “primary leukemic” and “non-leukemic” NHL patients disclosed striking differences in anatomic presentation and natural history of disease between T, B and null cell proliferations versus related cytologic types.