Chromosome studies in the non-Hodgkin's lymphomas: the role of the 14;18 translocation.

The 14;18 translocation [t(14;18)] is the most common chromosome abnormality noted in the non-Hodgkin's lymphomas (NHL). Although the translocation is seen in various histologic subtypes, it is most commonly associated with the follicular lymphomas, especially the small-cleaved cell (FSC) and mixed-cell (FM) subtypes. The translocation breakpoint has been cloned and DNA probes from the junction on chromosome 18 can now be used to detect the genetic consequences of the translocation in tumors with few dividing cells. This will allow a more precise classification of this subset of lymphomas and should lead to better understanding of the biology of this category of lymphomas. Finally, these insights will help in the development of more effective and possibly less toxic therapy.