Limb Salvage Strategy by Intra-Arterial Chemotherapy for Local Recurrent Osteosarcoma in Extremities

Osteosarcoma is the most common bone primary malignant tumor with high fatality rate. Since 1970’s, the survival rate of osteosarcoma increased significantly after the application of chemotherapy, and neo-adjuvant chemotherapy is not only effective in tiny metastases but also minimize the primary foci and clarify its boundary. To a large extent, the recent progress on the treatment of osteosarcoma results from the application of neo-adjuvant chemotherapy, and the limb salvage treatment of osteosarcoma has become the mainstream with the progress of neo-adjuvant chemotherapy, surgical techniques, and bone reconstruction, in which prosthesis replacement is one of the most commonly applied strategies. It is considered that limb salvage surgery should meet the following 3 prerequisites The primary osteosarcoma should be sensitive to chemotherapy on clinical and imaging indexes.

Enough tumor removal boundaries. Limb is reconstructed with enough function through simple, effective, and low risk mode to facilitate the recovery of postoperative chemotherapy as soon as possible. The main taboo of limb salvage surgery includes patients at too young age, and patients with huge tumor, soft tissue in terrible conditions, progressively enlarged tumor after chemotherapy, and local infection and failure in limb salvage therapy.

 The factors of local recurrence

No matter limb salvage surgery or amputation is applied, there is certain rate of metastasis and local recurrence, and it is commonly accepted that local recurrence would happen on 10% to 20% cases after limb salvage surgery. It is demonstrated that three factors are related to local recurrence, including the surgical margin, tumor necrotic degree after chemotherapy, and the anatomical relationship between tumor and neurovascular bundle. It is generally accepted that wide range excision is the primary principle of limb salvage surgery, which means soft tissue should be beyond tumor boundary for 2 to 3 cm under naked eyes, and bone is beyond tumor boundary for 3 to 5 cm, or operation should be ensured in normal tissues according to tumor free principle based on Enneking staging. It is controversial in clinic between limb salvage surgery and wide excision, as tumor usually affects nearby vessels and nerves which make it difficult to keep vessels, nerves, and enough soft tissues to enable both limb salvage surgery and wide excision at the same time. It is indicated that local recurrence is related to patients’ reactivity to chemotherapy, namely, local recurrence is more common in patients who has enough surgery excision scope but with poor reactivity to chemotherapy than the contrary. According to Grimer, no local recurrence happens even with marginal excision when tumor necrosis is more than 90% after chemotherapy, on the contrary, local recurrence happens in more than 36% patients who are insensitive to chemotherapy, and 4% in patients under wide excision margin but insensitive to chemotherapy.