Successful limb salvage after unplanned surgery for osteosarcoma

The “sandwich” treatment model of neoadjuvant chemotherapy–limb salvage/amputation surgery–chemotherapy is currently the classic treatment paradigm for osteosarcoma (OS). However, due to the high malignancy and characteristics of easy recurrence and metastasis of OS, unplanned surgery poses significant challenges to limb salvage surgery. A 40-year-old male patient with OS in the middle and lower segment of the right femur sustained trauma and underwent open reduction and internal fixation with a plate at a local hospital. Postoperative pathological examination revealed a malignant tumor. After receiving 2 cycles of AI (doxorubicin and ifosfamide) regimen chemotherapy at our hospital, he underwent limb salvage surgery. Postoperative pathology confirmed high-grade OS. The chemotherapy regimen was switched to the modified T19 regimen (doxorubicin, cisplatin, methotrexate, ifosfamide) for 9 cycles, with only grade 1–2 leukopenia, nausea, and vomiting, and no severe adverse events. A solitary pulmonary metastatic lesion was treated with microwave ablation. Currently, at 24 months post-surgery, the surgical wound has healed well, the right lower limb functions well with an MSTS (Musculoskeletal Tumor Society) score of 80%, and there is no evidence of tumor recurrence in the right thigh or lungs. For OS patients requiring reoperation following unplanned surgery, limb salvage remains challenging and should not be routinely recommended. In this single case, despite a 67% tumor necrosis rate (conventionally considered a poor response), limb salvage was achieved with negative margins and good short‑term functional recovery. Based on this experience, we cautiously suggest that, after multidisciplinary discussion and full informed consent, neoadjuvant chemotherapy followed by wide surgical resection and adjuvant chemotherapy may be considered in highly selected patients. However, this conclusion is derived from a single case report with a relatively short follow‑up (24 months) and the development of pulmonary metastasis. Further long‑term follow‑up and larger studies are necessary to confirm the safety and oncologic outcomes.