Functional outcome of surgical treatment of adults with extremity osteosarcoma after megaprosthetic reconstruction-single-center experience.

Background: Osteosarcoma is the most common primary malignant bone tumor in adults and is usually located in the long bones. Standard treatment consists of perioperative chemotherapy and radical surgical resection. Limb-sparing surgery using a variety of reconstructive techniques remains the gold standard.

Methods: In our study, we retrospectively analyzed 90 adult patients operated at our institution between 2000 and 2017 for extremity osteosarcoma that underwent limb-sparing reconstruction with the megaprosthesis. Sixty-one patients underwent resection and reconstruction of the distal femur, 9 patients-proximal femur, 7 patients-proximal tibia, 5 patients-total femoral resection and reconstruction, 5 patients-proximal humeral resection, and 3 patients-other types of resection with endoprosthetic reconstruction. The median follow-up time was 41 months, median overall survival was 86 months (3-225 months), and progression-free survival was 81 months (1-86 months). Functional assessment was made on 48 out of 56 living patients, after endoprosthetic reconstruction. The assessment was made according to MSTS functional scale.

Results: In 14 cases (15%), the endoprosthesis had to be explanted, or amputation was performed for local recurrence or septic complication. Due to a mechanical failure of the implant, we had to perform a revision in 5 patients (5%). Eighteen out of 74 patients with endoprosthesis died of the disease. The median MSTS score was 84% (53-100%), and the best result of 85% was achieved in patients after distal femoral resection with endoprosthetic reconstruction.

Conclusion: Careful planning of the treatment of patients with extremity osteosarcoma that is performed at the referral centers gives the possibility of long-term survival with a good and excellent functional result.