Case Report of Abdominal Recurrence of Osteosarcoma

Osteosarcoma is the second most common primary tumor of the skeletal system and the most common primary bone malignancy. Localized osteosarcomas are typically confined to the bone, with approximately 50% affecting the femur and 80% located near the knee (proximal tibia or distal femur). While pulmonary and osseous metastases are common, nonpulmonary, non-osseous sites are rare and underreported. We present the case of a 41-year-old woman treated for localized distal femur osteosarcoma who developed both local and abdominal recurrence 18 months posttreatment. The abdominal mass, located in the duodeno-pancreatic region, responded favorably to palliative chemotherapy.