Abstract. Reconstruction of the defect following limb-sparing resection of malignant bone tumors is controversial and extremely challenging. Extracorporeal irradiation (ECI) and re-implantation have been used for limb salvage surgery for patients, with major advantages, including biological reconstruction, ready availability and preservation of bone stock, over replacement with a megaprosthesis. The purpose of the present study was to present our experience and details of all patients treated with this surgery. Between June 2005 and December 2014, we followed-up 23 patients with limb malignancies who were treated with en bloc excision followed by 50-Gy single dose ECI and re-implantation of involved bone segments. All cases were evaluated based on clinical and radiological examinations, complications and Musculoskeletal Tumor Society (MSTS) score. Mean follow-up period was 77.6 months (range, 17-116 months). A total of 17 patients (73.9%) demonstrated no evidence of disease, 5 (21.7%) patients succumbed to the disease and 1 (4.3%) patient was alive with the disease at the final follow-up. Local recurrence occurred in 3 patients (recurrence rate, 13.0%) in the bed outside of the irradiated graft, and 4 of the 5 patients that lost their lives did so due to associated metastatic disease. The mean value of the MSTS score was 78.8% (50-93.3%). The majority of patients demonstrated solid bony union; however, 3 patients had non-union (13.0%) and 1 had a delayed union (4.3%). Early or late complications occurred in 11 patients (47.8%). Although the complication rate (47.8%) and re-operation rate (39.1%) were high, ECI and re-implantation may be a useful and cheap technique following en bloc resection for limb salvage in appropriately selected patients. IntroductionThe current management of musculoskeletal malignancies is limb sparing, and depending on the specific tumor, chemotherapy, surgery and radiotherapy are used in various combinations (1). Surgery is the mainstay of malignant bone tumor treatment with en bloc resection, followed by implantation of autograft, allograft or prosthesis to ensure skeletal continuity (1). Reconstruction, precise fit and stability of the materials are the main challenges to overcome. Different reconstruction methods have different advantages and disadvantages. Aseptic loosening of prosthesis and fracture of the allograft are common problems in clinical practice (2,3).In 1968, Spira and Lubin (4) first reported intra-operative extracorporeal irradiation (ECI) and re-implantation of resected bone as a useful method of limb salvage for malignant bone tumors. However, this method does not have a widespread use according to literature; it has only been used in some cases of osteosarcoma, Ewing sarcoma or chondrosarcoma with minimal lytic destruction or predominantly sclerotic changes (5). The dose of radiation produces a dead autogenous bone graft for re-implantation and reconstruction with correct dimensions. Available results have demonstrated excellent oncological outcomes in terms of loc...