Classical and Molecular Cytogenetics of Tumor Cells

Abstract

Cytogenetic findings are becoming increasingly important for the management of patients with malignant diseases, especially for those with hematologic neoplasias. The detection of aquired somatic mutations may help to establish the diagnosis of a neoplastic disorder and to rule out reactive changes due to toxic injury, vitamin deficiency or infections. Before, however, a chromosome aberration found in tumor cells can be taken as tumorassociated change it should be ruled out by chromosome analysis on PHA-stimulated blood lymphocytes that this chromosome aberration does not represent a constitutional abnormality. It is now clear that certain so-called primary chromosome abnormalities of tumor cells are associated with distinct clinico-histological disease entities. During tumor evolution additional chromosome aberrations appear and may determine the clinical course of the disease. Even these so-called secondary chromosome aberrations are non-randomly distributed throughout the genome. Therefore, cytogenetic studies are essential to make a specified diagnosis, to classify malignant disorders, to characterize the degree of neoplastic progression, to predict the prognosis, to test for remission, and to establish when relapse occurs. Thus, cytogenetic data can be of great help to select the appropriate treatment strategy.