Acute leukemia with Burkitt's tumor cells: A study of six cases with special reference to lymphocyte surface markers.

In six patients with acute leukemia (about 2% of the patients referred for acute lymphoblastic leukemia) the blast cells invading bone marrow and blood showed all the cytologic, cytochemical, and electron microscopy features of Burkitt's tumor cells. The presence of monoclonal surface immunoglobulins (their synthesis being proved by in vitro culture experiments), the binding of IgG aggregates, and the absence of rosette formation with sheep red cells documented the monoclonal B-cell origin of these blast cells which is in sharp contrast to the findings in common acute lymphoblastic leukemia. The course of the disease was usually rapidly fatal without chemotherapy-induced remission.