CD95 (FAS/APO-1) antigen is a new prognostic marker of blast cells of acute lymphoblastic leukaemia patients.

We analyzed CD95(Fas/APO-1) antigen expression on bone marrow blasts in 38 children with acute lymphoblastic leukemia (ALL) receiving a treatment in the Department of Leukaemias at the Cancer Research Center in 1987-1989 years (n = 22) and in 1994-1997 years (n = 16). CD95 antigen expression was studied by monoclonal antibodies (MoAbs) IPO-4 in indirect immunofluorescence analysis. CD95 antigen was expressed on 35.8 +/- 7.5% bone marrow blasts, most frequently (63.6%) in the clinically favourable Pre-B ALL. Only in this group CD95 antigen expression was correlated with CD10 antigen expression that has a positive influence to the time of complete remission in ALL patients. Our data showed that CD95 expression on blast cells is a favourable prognostic sign, associated with increased relapse-free and total survival. On the contrary, the absence of CD95 antigen on blasts is an unfavourable sign for disease evolution.

Nonrandom chromosomal abnormalities in acute lymphoblastic leukemia of childhood.

The leukemic cell karyotype was studied in 103 children with acute lymphoblastic leukemia. An abnormal chromosome pattern was revealed in 81 of 98 patients studied before treatment (82.6%) and in the five children studied in relapse. Aside from specific chromosomal abnormalities defined by the Third International Workshop on Chromosomes in Leukemia, other nonrandom rearrangements were observed, particularly del(14)(q11-13), del(12)(p11-12), and t(1;19)(q22-23;p13), often associated with partial trisomy for 1q. Patients with del(14) had tumorous lymph-nodes or other extramedullary tumors. The course of the disease in these children was rapid. Patients with markers such as Ph, 6q-,14q+, and with a t(4;11) had a low incidence of complete remission and short survival. The most favorable course of the disease was observed in the group of children with over 50 chromosomes in the leukemic cells.

Chromosomes in acute nonlymphocytic leukemia.

The karyotype of leukemic cells was studied in 88 acute nonlymphocytic leukemia (ANLL) patients. Chromosome abnormalities were discovered in 78.4% of all patients and in 72.5% of the 69 patients studied before treatment. Characteristic abnormalities: translocations 8;21, 15;17, 9;22 or 6;9, rearrangements of 11q, gain of chromosomes 8 or 21, and loss or deletion of chromosomes 5 or 7 were detected in 56 of 69 patients with abnormal karyotypes. Translocation 8;21 was revealed in 27 patients; 20 of them had M2 FAB-form, four had M1, and three had M4. In patients with t(8;21) the incidence of complete remission was higher and the duration of first remission and survival longer than in patients with other abnormalities or with a normal karyotype.

Chromosome abnormalities in chronic myeloid leukemia in children.

Banded chromosomes of leukemic cells were studied in 53 children with chronic myeloid leukemia (CML). Ph1 chromosome was found in 21 children, and the remaining 32 cases were Ph1 negative. Besides Ph1 translocation additional chromosomal abnormalities, including marker i(17q), were revealed in three of eight children studied in blastic crisis of Ph1 positive CML. Leukemic cells of most patients with Ph1 negative CML possessed normal karyotype. Clones with chromosomal abnormalities were found in 12 of 32 cases. Most characteristic were monosomy 7 (in four children) and trisomy 8 (in three). Abnormal karyotype may be a bad prognostic sign in Ph1 negative CML. The presented data confirm the difference in age of appearance, bone marrow pattern and clinical course between Ph1 positive ("adult") and Ph1 negative (juvenile) types of CML in children. Probable prenatal commencement of CML in babies and children in the first years of life is discussed.