Abstract
Chronic granulocytic leukemia (CGL) is cytogenetically an interesting disease because of the presence of Philadelphia (Ph1) chromosome and the appearance of new chromosomal changes throughout their course in about 75% of the cases. As the majority of new chromosomal changes occur shortly before or during the acute phase, they are as one of the predictive or diagnostic indicators of the acute crisis. However, some cases keep the chronic phase in spite of the presence of new chromosomal changes. If the state of new chromosomal changes in the chronic phase can be differentiated from that in the acute phase, chromosomal examination will be more useful for the understanding of the progress of the disease.
The analysis by banding method of our 21 cases and 120 cases in the literature with one or more additional chromosomes in addition to Ph1 revealed the followings.
1. Such chromosomal aberrations as the extra 8, i (17 q), the extra Ph1, missing Y and balanced rearrangement could appear not only in the acute phase but also in the chronic phase. Consequently when these chromosomal aberrations are found, we should not make the diagnosis of acute crisis but carefully follow up their clinical course.
2. Those chromosomal aberrations such as the number of chromosomes exceeding 48, i (17 q) with additional chromosomal aberration, autosomal elimination, unbalanced rearrangement and the abnormality of X chromosome appeared in the acute phase. These chromosomal aberrations might be useful diagnostic indicators of the acute crisis of CGL.
