Cytogenetics and molecular pathology in cancer diagnostics

The importance of cytogenetic and molecular genetic changes in cancer diagnostics has long been recognized. Especially chromosomal translocations have an established role in diagnosis, prognosis, and prediction of response to treatment in hematologic malignancies. Today some leukemias are classified according to cytogenetic changes. Characterized translocations have provided instrumental clues to understanding of molecular mechanisms of cancer, which in turn have enabled development of molecularly targeted treatments. This paper reviews the diagnostic significance of novel cytogenetic and molecular genetic techniques in human malignancies. Not only in hematologic malignancies and sarcomas but also in neurogenic tumors and carcinomas numerous diagnostically, prognostically, predictively and therapeutically important genetic changes have been described over the past few years, and novel genetic markers are discovered at a rapidly growing rate. New methods and characterized specific genetic markers have opened a new era also in detection of minimal residual cells.