Simple monosomy 7 and myelodysplastic syndrome in thirteen patients without previous cytostatic treatment

Abstract

Thirteen patients with simple monosomy 7 presented with pallor in 11, easy bruisability in five, splenomegaly in four, no infections, refractory anaemia in all, granulocytopenia in seven, monocytosis in three, leucocytosis in four and thrombocytopenia in eight. Peripheral blood and bone marrow findings were consistent with myelodysplastic syndrome (MDS) type I in three, type II in two, type III in two, type IV in three and acute myelofibrosis in three patients. Transformations to acute leukaemia in seven patients were M2 in one, M4 in four, megakaryoblastic in one and undifferentiated in one. Lack of chromosome 7 in 12-85% of analysed cells at initial presentation of MDS progressed to nearly 100% during blastic transformation. At that time an additional change in the long arm of chromosome 3 was seen in two patients and trisomy 8 in 6% of analysed cells in a third case. The median survival time was 12 months for MDS and 3 months for acute leukaemia. Simple monosomy 7 appears to be largely confined to young children and elderly people.

Detection of chromosomal 7 loss in myelodysplasia using an extremely polymorphic DNA probe

“…Ten of the 118 (9%) MDS patients who were informative for the pAg3 locus showed marked, unequal intensities of the two allelic bands. This result is in keeping with the numbers of monosomy 7 abnormalities detected in MDS in several studies (Heim & Mitelman, 1986;Michiels et al, 1986;Yunis et al, 1986;Jacobs et al, 1986). In fact the ten patients who showed loss of one of the chromosome 7 homologues by RFLP analysis include all five patients demonstrated to have full or partial monosomy 7 by cytogenetic analysis.…”

“…Using conventional cytogenetic techniques about half of all MDS patients show clonal chromosomal abnormalities (Heim & Mitelman, 1986; Second International Workshop on Chromosomes in Leukaemia, 1979), the most frequent cytogenetic abnormalities being partial or complete loss of chromosome 5 or 7, and trisomy 8. The presence of specific lesions like monosomy 7 and complex karyotypic abnormalities are associated with a higher risk of transformation to acute leukaemia (Michiels et al, 1986;Borgstrom, 1986;Todd & Pierre, 1986).…”

Familial bone marrow monosomy 7. Evidence that the predisposing locus is not on the long arm of chromosome 7.

“…Bone marrow monosomy 7 or 7q-is also found in some patients with AML who have no prior history of car-cinogen exposure (3,6). The age distribution of these de novo cases shows peaks in the first and fifth decades (6). Overall, monosomy 7 or 7q-is identified in -5% of de novo and in 40% of secondary cases of AML (1,(3)(4)(5).…”

“…Monosomy 7 or 7q-is the most common abnormal karyotype in cases of AML that occur after cytotoxic cancer therapy (1,3) or occupational exposure to mutagens (5). Bone marrow monosomy 7 or 7q-is also found in some patients with AML who have no prior history of car-cinogen exposure (3,6). The age distribution of these de novo cases shows peaks in the first and fifth decades (6).…”

Detection of monosomy 7 by fluorescenceIn situ hybridization in acute nonlymphocytic leukemia and myelodysplastic syndrome

“…Tachibana et al (1988) reported that the monosomy 7 genotype was detected in erythroid as well as gran-ulocyte/macrophage progenitors in patients with MDS using the colony assay technique. Thus, the target cell of clonal neoplastic change is hypothesized to be a primitive hemopoietic progenitor cell capable of differentiating into granulocyte/ monocyte, erythrocyte, and megakaryocyte lineages (Michiels et al, 1986).…”