[Cytochemistry of leukocytes in children. IV. The use of cytochemical tests in the differentiation and prognostic evaluation of acute leukemias].

From 63 children with acute leukaemia the bone-marrow smears were cytochemically examined before the beginning of therapy. The activity of peroxydase was examined according to Sato and Sekya, that of acid phosphatase according to Löffler and Berghoff, that of alpha-naphthyl-acetate-esterase according to Gomori; the evidence of glycogen was examined by means of the PAS-diastase response according to McManus. Among the 63 cases of leukaemia we found 6 cases of paramyeloblastic leukaemia, 2 cases of parapromyelocytic leukaemia, and 3 cases of myelomonocytic leukaemia. 52 cases of leukaemia could not be further differentiated in morphological respect. They represented an immature paraleukoblastic leukaemia. A division according to leading cytochemical criteria was made for them. The therapeutic possibility of influencing the various groups was checked by means of prolonged observations. Children affected with paraleukoblastic leukaemia of the phosphatase type had a significantly low rate of remission similar to the myeloid leukaemia. Paraleukoblastic leukaemia of the PAS type, esterase type and the undifferentiated type revealed no essential differences. The rate of remission, however, was highest in leukaemia of the PAS type amounting to 100%. In one part of patients the prolonged cytochemical observations in 8 children with recidives showed that the cytochemical type under chemotherapy was changed.