title: Leukemic transformation in patients with the 5q- alteration: analysis of the behavior of the 5q- clones in preleukemic to leukemic phases.
abstract: Serial cytogenetic studies have been performed in four patients with myelodysplastic syndromes. In all four a 5q- alteration was present, but with a different pattern of presentation. One patient presented 5q- as the only alteration since diagnosis; two patients acquired this alteration during the course of the disease; and the fourth showed a 5q- plus other alterations since the first cytogenetic study. Likewise, three of the four patients showed a clone with trisomy 8 and without 5q-. According to these observations and others from the literature with similar cytogenetic behavior, we have analyzed the following points: 5q- as a primary event and as the only alteration, 5q- as a secondary event, 5q- plus other alterations, and presence of cytogenetically different clones. Analysis of these points suggests that the 5q- alteration can represent an early mutation conferring a slow capacity of expansion to the affected clones, with the possibility of cytogenetic evolution during the progression of the disease (about 30% of the patients). Likewise, the association of trisomy 8 clones with 5q- clones can be a nonrandom event.
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000648:ultrastructure; D002872:Chromosome Deletion; D002895:Chromosomes, Human, Pair 5; D002898:Chromosomes, Human, Pair 8; D002999:Clone Cells; D005260:Female; D006801:Humans; D007621:Karyotyping; D007938:Leukemia / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000235:genetics* / Q000473:pathology; D011289:Preleukemia / Q000235:genetics* / Q000473:pathology; D014314:Trisomy