[Molecular genetics of malignant non-Hodgkin's lymphoma]

Molecular genetical analyses are a valuable adjunct in the diagnosis and biological characterization of malignant lymphomas. They help to define clonality, lymphocyte lineage, and stage of differentiation of the lymphocyte clone. Investigations on the immune receptor gene rearrangement status can now be carried out by the fast and robust polymerase chain reaction (PCR) technique. However, this approach has its drawbacks and cannot completely substitute for Southern Blot experiments. Oncogene rearrangements are used not only to define clonality, but also give an idea about the origin of a lymphocyte clone in malignant lymphoma from a morphologically defined lymph node compartment. One has to be aware of the fact that gene rearrangement studies can only provide reliable results on the basis of a sound morphological evaluation of the lymphoid tumour tissue and that clonality of a lymphoproliferative disease does not necessarily imply a malignant course of disease for the patient.