[Lymphadenopathy: demarcation to malignant lymphomas]

Recognition of the differential diagnosis between lymphadenitis and malignant lymphoma requires good knowledge of the basic forms of the disease as well in depth knowledge of the structure of the individual compartments. There are defined forms of lymphadenitis where the differential diagnosis to certain lymphoma entities is known. Other reactive structural alterations show indistinct limits so that a decision is only possible after using additional techniques, such as immunohistochemistry and molecular analyses. Finally, there are marginal areas which can only be clarified by including clinical data.