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Successful treatment via chemotherapy and surgical resection of a femoral hemangiopericytoma with pulmonary metastasis.

Hemangiopericytoma (HPC) is a soft-tissue neoplasm composed of proliferating capillary pericytes. It has variable and unpredictable malignancy and most commonly occurs in the fifth or sixth decade of life. Diagnosis is based on the histological aspect. HPC is exceedingly rare in childhood. In both adults and children, curative surgery is the most important predictor of survival. The place of chemotherapy in the treatment of HPC is not well established. We describe a case of adult-type metastatic HPC of the thigh in a 13-year-old boy. The response to neoadjuvant chemotherapy was excellent, and local control of this initially unresectable tumor was achieved without radiation therapy or mutilating surgery. The child is alive and well and has had 8 years of follow-up after treatment.