Hemangiosarcoma of the Bone. Problems Arising from the Heterogeneity of Malignant Vascular Tumors of the Bone

BACKGROUND: Hemangioendothelioma of the bone is a rare vasoformative tumor of the bone with an intermediately aggressive nature. The tumor is said to have a long clinical course depending on the sites involved. Diagnosis is particularly difficult since vascular tumors of the bone often present heterogeneous differentiation. CASE REPORT: We report on a 65-year-old female patient who had been diagnosed with an epitheloid hemangioendothelioma of the iliac bone and who underwent wide local excision. Although the initial biopsy specimens had clearly shown an epitheloid hemangioendothelioma, the final pathological analysis revealed a heterogeneous tumor, partially with some characteristics of an epitheloid hemangiosarcoma. The patient subsequently developed pulmonary metastasis, received a multimodality treatment, but died 14 months after the initial diagnosis from pulmonary insufficiency due to pleural sarcomatosis. CONCLUSION: Hemangioendothelioma of the bone needs to be discussed as a differential diagnosis of osteolytic lesions. Our case stresses the importance of multimodality treatment in centers for cancer treatment. Histopathologic evaluation is essential in the diagnosis of epitheloid hemangioendothelioma. It is particularly difficult due to the heterogeneous differentiation of vasoformative tumors of the bone.