Phagocytosis in acute leukemia.

The phagocytic potential of leukemic cells in various types of acute leukemia was studied. Cases included lymphoblastic leukemia, myeloblastic leukemia, myelomonocytic leukemia, monocytic leukemia, progranulocytic leukemia, blast transformation of chronic myelocytic leukemia, and unclassified leukemias. Cytochemical stains were used as an aid in classification. These included Sudan black B, naphthol AS-D chloroacetate esterase, alpha-naphthyl butyrate esterase, acid phosphatase, and periodic acid-Schiff. Phagocytosis was evaluated after incubation of leukemic cells with Candida albicans. Rare phogocytic activity was seen in lymphoblastic leukemia, unclassified leukemias, blast crises in chronic myelocytic leukemia, and progranulocytic leukemia. Myeloblastic leukemias were feebly phagocytic. Myelomonocytic leukemia and monocytic leukemia both exhibited marked phagocytosis which distinguished them from the other acute leukemias. Myelomonocytic leukemia could be differentiated from acute monocytic leukemia by its greater phagocytic capacity.