Three coexisting lymphomas in one patient: genetically related or only a coincidence?

The simultaneous manifestation of different lymphomas in the same patient or even in the same tissue, defined as composite lymphoma, is very rare. The exceptional case of a patient who, presented with simultaneous manifestation of three different lymphomas after 30 years of successful treatment of a nodal T cell lymphoma is reported here. The three lymphomas were: (1) primary cutaneous marginal zone B cell lymphoma (MZBL); (2) nodal Epstein-Barr virus (EBV)-associated classic Hodgkin's lymphoma (cHL) of the B cell type; and (3) peripheral T cell lymphoma coexisting in the skin and cervical lymph node. Immunohistochemical and molecular analyses showed different clonal origins of EBV-negative cutaneous MZBL and EBV-positive B cell cHL and, in addition, the presence of the same clonal T cell population in the skin and lymph node. The simultaneous occurrence of three different, clonally unrelated lymphomas in one patient at the same time has not been reported yet.