[Introduction to the cytogenetic study of acute leukemias].

Chromosome banding techniques have been useful to define abnormal chromosomes in acute leukemia. The comparison between cases reported from different centers has been possible only with the acceptance of a universal system of classification and nomenclature for acute leukemia as well as for chromosomal rearrangements. Chromosomes abnormalities in acute leukemia are found in about 50 per cent of patients. They appear to be non random. Clinical, morphologic and cytogenetic findings have been correlated. Diagnosis and prognosis significance of chromosome abnormalities is of importance. The problem of normal or so called normal cells in 50 per cent of acute leukemia is set.