Metastatic multicentric epithelioid angiosarcoma of bone. A case report with pitfalls. Tumor seeding after percutaneous biopsy and hypercalcemia

BACKGROUND: Angiosarcomas are a type of malignant tumor of vascular origin. They represent less than 1% of all primary bone tumors. The multicentric or metastatic does not differ in its high aggressiveness and poor prognosis. CASE PRESENTATION: We describe a case of an elderly male with bone angiosarcoma initially located in proximal femur. After biopsy in a non-expert sarcoma center, he presented a tumor involvement in the path of the needle, in additional finding of multicentric/metastatic that involve the sacro-coccygeal level assessed by magnetic resonance imaging. He associated tumoral hypercalcemia secondary to malignancy and was referred to our sarcoma center for therapeutic decision. He was treated by tumoral resection and reconstruction with proximal femur tumor prosthesis due to high risk of pathological fracture. In the early follow-up he presented pulmonary metastasis and new sarcoma implants in soft parts, dying a few months later. CONCLUSIONS: Multicentric and/or metastatic epithelioid angiosarcomas require diagnostic and therapeutic thoroughness to improve the patient's quality of life and survival. Percutaneous biopsies have a risk of tumor seeding in the needle trajectory; therefore, they must be performed in centers with expertise in sarcomas. At present, multicentric or metastatic bone involvement is only of theoretical relevance since the treatment and prognosis are identical. Despite that hypercalcemia in sarcomas is a rare problem, the case has this peculiarity, and we highlight its investigation in some of these cases.