Cutaneous T cell lymphoma and classic Hodgkin lymphoma of the B cell type within a single lymph node: composite lymphoma.

Composite lymphomas are defined as two unrelated, morphologically and genetically distinct lymphomas occurring at the same point in time within the same tissue or organ. Since their original definition, several composite lymphomas have been reported exclusively based on morphological grounds. However, with the application of immunohistological and molecular biological techniques it has become evident that many so called "composite" lymphomas do not fulfil the necessary criteria, because they merely represent two different morphological phenotypes of the same malignant clone. This report describes the manifestation of a true composite lymphoma within a single cervical lymph node, which is composed of a cutaneous T cell lymphoma and a classic Hodgkin lymphoma of B cell type--a very rare finding indeed.