Discordant lymphoma: report of two cases and review of the literature

The simultaneous occurrence of two different histologic types of lymphoma i n one location ("composite" lymphoma) or in different anatomical locations ("discordant" lymphoma) is uncommon, particularly the association of Hodgki n's disease (HD) and non-Hodgkin's disease (NHD). Therefore, both condition s have long been considered well differentiated entities, and its associati on qualified as a chance event. Two cases of "discordant" lymphoma are repo rted. In both cases the histologic type was HD with mixed cellularity, asso ciated with immunoblastic B lymphoma in case 1 and CLL-B in case 2. Some re cent series seem to indicate that this phenomenon occurs more commonly than what could be reasonably attributed to chance alone, suggesting the analys is of cases associating HD and NHD with CLL-B a possible clonal relationshi p between these conditions. The Reed-Sternberg cell might thus originate fr om an altered B-lymphocyte.