[Clinical evolution and cytogenetic study of two acute lymphoblastic leukemia (type L2) in the child: prognostic value of the karyotype].

Cases of two newborns with acute lymphoblastic leukemia (ALL) L2 type, are reported. In each case, some chromosomal abnormalities can be found. In the first case, a translocation t (4;11) is noticed. It has to be compared with already published patients' cases and so the non randomly occuring character of those alterations in ALL and poor pronostic factor can be confirmed. In the second observation, a complex translocation t (5;6;X) never described before in literature, was observed. Chromosomal findings in ALL are not only a help to diagnosis but, by cytogenetic data, are also a help to accurate prognosis and adequate treatment.