A Rare Case of Bone Marrow Metastasis of a Splenic Angiosarcoma

We report a rare finding of bone marrow metastasis from an angiosarcoma of the spleen with secondary involvement of the liver. The patient was a 43-year-old woman who initially presented with anemia, thrombocytopenia, and a high-grade angiosarcoma of the spleen with focal metastasis to liver. She was later treated with chemotherapy but continued to be anemic and thrombocytopenic. Bone marrow biopsy revealed moderate infiltration by angiosarcoma with typical features of spindle tumor cells and anastomosing vascular channels. Immunohistochemical studies revealed the tumor cells to express the endothelial markers CD31, CD34, and factor VIII. Angiosarcomas are rare and aggressive tumors. Although angiosarcomas frequently metastasize to the solid organs, bone marrow metastasis has been rarely documented. However, in view of several other reported cases of angiosarcoma of the spleen with metastasis to the bone marrow, it has been proposed that angiosarcomas have a rare propensity for bone marrow infiltration.