Hodgkin's and Castleman's disease in a patient with systemic mastocytosis.

Systemic mastocytosis is a rare condition characterized clinically by the local consequences of vasoactive peptides released from infiltrating mast cells in the reticuloendothelial tissues. Mast cells originate from the pluripotent bone marrow stem cells; it is therefore not surprising that myeloproliferative and myelodysplastic disorders commonly coexist or terminate the clinical phase of mastocytosis. We report here, to our knowledge, the first case of Hodgkin's and Castleman's disease occurring in a patient with co-existent systemic mastocytosis, which remained unchanged after combination chemotherapy for Hodgkin's disease.