Outcomes of stage IIB osteosarcoma treated by limb salvage surgery using extracorporeally irradiated (ECI) autograft

Background: Extracorporeally irradiated (ECI) technique is an alternative of limb salvage procedure in treating osteosarcoma regarding limitation of endoprosthesis and allograft. This study evaluated the outcomes of limb salvage surgery using extracorporeally irradiated (ECI) autograft and its correlation with patient’s characteristics. Methods: Retrospective cohort design was performed to study 20 patients with stage IIB osteosarcoma treated by ECI autograft from 1995 to 2008. Survival, local recurrence, metastases, complications, union time and functional score based on Musculoskeletal Tumor Society scoring system-(MSTS) were evaluated. Kaplan-Meier method was used to describe survival, local recurrence free survival, and metastases free survival. The correlation among patient’s characteristics that were age, gender, duration, site of tumor size, type of osteosarcoma, SAP (serum alkaline phosphatase) level, type of biopsy, and type of Huvos were analyzed by Log rank test. Chi-square test was used to analyze the correlation between MSTS score and patient’s characteristics, local recurrence, metastases, complications. Results: Five-year survival was 54.97 ± 9.8%, five-year local recurrence free survival was 66.5 ± 7.6%, and five year metastasis-free survival was 57.13 ± 10.04%. Six patients died, five were due to lung metastases and one due to complication of chemotherapy. Three underwent amputation after local recurrence. Kaplan-Meier curve showed that a good type of Huvos (III, IV) always gave better survival, local recurrence free survival, and metastases free survival than poor type of Huvos (I,II). Normal SAP level gave better local recurrence free survival compare to increased level of SAP. Mean of union rate was 8.13 months. MSTS mean score was good (70.63%) in patients with no evidence of disease. MSTS score was poor in patients with local recurrence (p=0.025), metastases (p=0.01), complications (p=0.03), and the combined of those three outcomes (p=0.001). Conclusions: Functional outcome was poor in patients with local recurrence, metastases, and complications. SAP level and type of Huvos could be studied further as predictive factors for the outcomes (survival, local recurrence, metastases).