EXPRESSION OF FAS ANTIGEN IN ACUTE MYELOID-LEUKEMIA IS ASSOCIATED WITH THERAPEUTIC RESPONSE TO CHEMOTHERAPY

Plow cytometric immunofluorescent analysis was used to assess Pas anti gen (CD95) expression in blasts obtained from the bone marrow of 30 pa tients with acute myeloid leukaemia. The percentage of positive cells in each sample was highly variable. Pas antigen expression did not cor relate with age, FAB subtype, white blood cell counts, or CD34 express ion. Low expression of Pas was associated with a low complete remissio n rate after induction chemotherapy (62 . 5% in cases with <20% positi ve cells v 92 . 9% in cases with greater than or equal to 20% positive cells. P<0 . 01). The main cause for not achieving remission was resi stant disease. Our results suggest that the quantitation of Pas expres sion can be predictive of treatment outcome in acute myeloid leukaemia .