A case of primary splenic histiocytic sarcoma.

Abstract

A case of primary splenic histiocytic sarcoma is reported.A 29-year-old man was admitted to Fukushima Medical College Hospital for pretibial edema. Physical examination showed splenomegaly without lymphadenopathy and hepatomegaly. Laboratory findings revealed thrombocytopenia and hypoproteinemia, and bone marrow aspirate and biopsy were normal. Clinically, splenic malignant lymphoma was suspected and surgical splenectomy was performed. His symptoms resolved after the treatment.The spleen weighed 730g and a well-defined reddish-colored tumor was observed on cut surface. The tumor was composed of an intense infiltration of variable sized histiocytic cells, from 8μm to 20μm in diameter, containing abundant eosinophilic cytoplasm and large round to oval nuclei.Mitotic figures were a few and multinuclated giant cells were occasionally seen. The tumor cells were considered as monocyte/histiocyte series based on cellular morphology and immunological charactaristics for monocytic markers and germline of immunogloblin heavy chain (JH) and T-cell recepter beta chain (Cβ1) genes. Flow-cytometric DNA analysis showed a hypodiploidy pattern. These findings indicate that the present case is primary splenic histiocytic sarcoma with low grade malignancy.