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Intentional marginal resection of periosteal osteosarcoma in combination with neoadjuvant chemotherapy: A report of two cases and a review of the literature.

A wide resection of the tumor with or without chemotherapy is the treatment of choice for periosteal osteosarcoma (PO) of the extremities, however, post-operative limb function and quality of life could be compromised. The present study reports two cases of 14-year-old boys who presented with progressively enlarging masses in their right knee regions. Computed tomography and magnetic resonance imaging scans indicated a fusiform space-occupying mass encircling the bone cortex, with stippled calcification. A diagnosis of PO was suspected. The histological findings confirmed the diagnosis of intermediate PO. Pre-operative chemotherapies were started, and good responses were detected by clinical evaluation and histological findings. Surgeries preserving the functional structures, including neurovascular bundles, tendons, muscles and epiphyses, were performed, followed by routine chemotherapy. The two patients experienced disease-free survival with follow-up times of 37 and 108 months, respectively. The patients were satisfied with the results of the treatment and they returned to normal life activities. These two cases indicated that a marginal resection of the tumor in conjunction with effective neoadjuvant chemotherapy may be an ideal alternative treatment for intermediate PO, since survival along with well-preserved limb function could be guaranteed. By contrast, a wide excision could result in the loss of limb function.