Treatment Option Overview for Osteosarcoma and UPS of Bone

It is imperative that patients with proven or suspected osteosarcoma have an initial evaluation by an orthopedic oncologist familiar with the surgical management of this disease. This evaluation, which includes imaging studies, should be done before the initial biopsy because an inappropriately performed biopsy may jeopardize a limb-sparing procedure. Additionally, protective weight bearing is recommended for patients with tumors of weight-bearing bones to prevent pathological fractures that could preclude limb-preserving surgery.

Successful treatment generally requires the combination of effective systemic chemotherapy and complete resection of all clinically detectable disease.

Randomized clinical trials have established that both neoadjuvant and adjuvant chemotherapy are effective in preventing relapse in patients with clinically nonmetastatic tumors.[1]; [2][Level of evidence A1] The Pediatric Oncology Group (POG) conducted a study in which patients were randomly assigned to either immediate amputation or amputation after neoadjuvant therapy. A large percentage of patients declined to be assigned randomly, and the study was terminated without approaching the stated accrual goals. In the small number of patients treated, there was no difference in outcome between those who received preoperative chemotherapy and those who received postoperative chemotherapy.[3]

The treatment of osteosarcoma also depends on the histological grade, as follows:

Recognition of intraosseous well-differentiated osteosarcoma and parosteal osteosarcoma is important because patients with these tumor types have the most favorable prognosis and can be treated successfully with wide excision of the primary tumor alone.[4,5] Patients with periosteal osteosarcoma have a generally good prognosis [6] and treatment is guided by histological grade.[5,7]

Patients with undifferentiated pleomorphic sarcoma (UPS) of bone are treated according to osteosarcoma treatment protocols.[8] A sarcoma-specific survival rate of 70.7% has been reported using primarily cisplatin- and doxorubicin-based regimens.[9]

Imaging modalities such as dynamic magnetic resonance imaging or positron emission tomography scanning are noninvasive methods to assess response,[10-18] and are the preferred modalities in the Children's Oncology Group AOST2032 (NCT05691478) trial.

Table 3 describes the treatment options for localized, metastatic, and recurrent osteosarcoma and UPS of bone.