Cytogenetical changes in Philadelphia chromosome-positive chronic myelogenous leukemia
Carbonell, F.; Grilli, G.
Medicina Clinica 77(10): 420-423
1981
ISSN/ISBN: 0025-7753 PMID: 6948987 Document Number: 175137
Twelve cases of Philadelphia chromosome positive chronic myelogenous leukemia are described. In all clonal evolution was observed. Four cases were studied in the chronic phase, 3 in the transition phase and 5 in both phases. In all cases, clonal evolution was characterized by the appearance of chromosomal alterations besides the Philadelphia chromosome, or by the dominance of the Philadelphia chromosome of the normal cytogenetic lines. In the cases where new alterations were identified with Giemsa stain-trypsin bands, the duplication of Philadelphia chromosome, trisomy 8 or the 17q isochromosome was confirmed as specific for acute transformation. The clonal evolution in chronic myelogenous leukemia appears to have 2 phases. The 1st occurs during the chronic phase, when a slow but progressive change from negative to positive Philadelphia cells takes place. The 2nd, faster change is characterized by a substitution of positive Philadelphia cells by others which, together with this alteration, present new anomalies which are typical of the acute phase. During the chronic phase, treatment does not influence the clonal evolution, but during the acute phase treatment can modify the cytogenetic picture.