摘要： Immunophenotyping is an essential part of the modern diagnostic workup of acute leukemias and thus for an appropriate treatment of these complex and heterogeneous diseases. It provides a lot of useful information in this setting that transfers directly from laboratory to clinical management of patients. Lineage definition is the first goal leading to proper initial therapy. Some phenotypic patterns define specific subsets correlating with poor (mixed phenotype, dendritic cell neoplasm) or favorable (cortical T-lymphoblastic leukemia) outcome, thus guiding the application of treatment modalities. An advanced analysis of phenotypic data can address specific issues, such as the still debated role of multilineage dysplasia. The quality of response to chemotherapy is monitored by the detection of minimal residual disease and peripheral blast clearance during chemotherapy delivering. That allows a sharp discrimination of prognosis and again can drive the intensity of therapies proportionally to the disease chemosensitivity.