Primary angiosarcoma of bone. A case report.

BACKGROUND: Primary malignant vascular tumors of bone are very rare accounting for less than 1% of primary bone malignancies. They are characterized by unknown etiology, variable biologic behavior and histological appearance. Angiosarcoma is an aggressive malignant vascular tumor derived from mesenchymal cells with endothelial differentiation. CASE REPORT: We present a rare case of angiosarcoma of bone in a 47-year-old male operated for a lumbar disk herniation. During his transportation from the operation theater, a pathological intertrochanteric fracture of the right hip occured. The magnetic resonance imaging (MRI) revealed a bone lytic lesion located into the great trochanter of the right femur. Open surgical biopsy of the lesion was performed and the histological examination showed primary angiosarcoma of bone. The treatment included radiotherapy (300 cGy per fraction in 13 days) followed by excision of the proximal femur and custom made total hip arthroplasty. The diagnosis was confirmed on the surgical specimen.

Posterior mediastinal Castleman's disease presented as hypervascular lipomatous tumor.

Castleman's disease (CD) is a rare lymphoproliferative disorder most often found in the chest. Herein we describe the imaging findings of a histologically proven case of CD involving the posterior mediastinum in a 41-year-old asymptomatic man presented as a well-defined hypervascular lipomatous tumor. To our knowledge less than 10 cases of posterior mediastinal CD have been reported so far and this is the first case of CD mimicking mediastinal lipomatous tumor.