Skip Metastases in Osteosarcoma: Experience of the Cooperative Osteosarcoma Study Group

Purpose The outlook for patients with osteosarcoma who present with synchronous regional bone metastases (skip metastases), either in the primary bone site or transarticular, is considered to be extremely poor. This study was conducted to further investigate the prognostic implication of skip metastases in osteosarcoma. Patients and Methods The authors retrospectively analyzed the collected data of 1,765 consecutive patients with newly diagnosed high-grade osteosarcoma of bone who were registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies and identified 24 patients (1.4%) with unequivocally proven skip metastases. All 24 patients were treated by an aggressive surgical approach coupled with polychemotherapy. Demographic, diagnostic, tumor, and treatment-related variables and response and survival data were analyzed. Results Skip metastases were identified preoperatively in 11 of 24 patients by bone scan, eight of 22 patients by plain x-ray, 15 of 18 patients by magnetic resonance imagi...