Chromosome changes in hematologic malignancies

Evidence has now accumulated that chromosome changes are among the critical events that lead to malignant transformation of cells. More sophisticated analysis of clinical and cytogenetic parameters will lead to identification of additional subtypes of hematologic neoplasms such as t(15;17) APL or Ph1-positive CML. This differentiation has both diagnostic and prognostic importance. Cytogenetic studies currently in progress may reveal etiologic factors in malignant transformation; occupational exposure to potential mutagens, previous cytotoxic therapy, ethnic background, or a family history of cancer may correlate with specific chromosome abnormalities and specific subtypes of leukemia and lymphoma. As our knowledge of the human gene map increases, we expect to be able to relate changes in the affected chromosomes to biochemical abnormalities in the malignant cell. This will improve our understanding of how selected cells gain a proliferative advantage through malignant transformation, and it will aid in the precise classification of these diseases and thus lead to the design of more specific forms of therapy.