IMMUNOBLASTIC LYMPHOSARCOMA, CYTOLOGICAL AND CLINICAL ENTITY

Abstract

Twenty cases of hematosarcomas belonging to lymphosarcomas (T [thymus-derived] or B [bone marrow-derived] cell markers, absence of reticulosarcoma characters in sections, on smears, with conventional and scanning electron microscopy) were studied. Their cells which appear as large pyroninophilic cells on sections, as large basophilic cells with blastic nuclei and often cytoplasmic vacuoles on smears, as having many polyribosomes and usually no ergastoplasm with conventional electron microscopy, and as large cells of the lymphocytic series with scanning electron microscopy resemble the cells described in adenitis in 1955 and in the graft-vs.-host-reaction in 1961, which Gowans showed resulted from lymphocyte transformation, and which Dameshek called immunoblasts. Many of these cases of immunoblastic lymphosarcoma (ILS), identified by their cytohistological characteristics [also recognized by Lukes et al. and Lennert et al.], present etiological, clinical and pronostic characters which show that it may be not only a cytological entity but also a cytoclinical entity. It affects males in 85% of the subjects; 8 patients came from Mediterranean countries outside France; 2 patients had a history of chronic rheumatoid manifestations. The disease was at stage IV at the 1st presentation in 10 patients. It was revealed by profound (mediastinal or abdominal) localizations in 60% of cases (12 of 20). If presented hypoglobulinemia in 8 of 13 patients. In 6 of the 15 patients treated before leukemic conversion, chemotherapy, usually efficient in lymphosarcoma (LS), failed to induce remission. This type of LS has a poorer prognosis than other types of LS (median for all stages: 8 mo.). It led to death after its conversion to leukemia (9 of 20 cases), or by vital organ (as brain or kidney) infiltrations.