Locally Advanced Osteosarcoma

This phase II trial studies the effect of atezolizumab and cabozantinib in treating adolescents and young adults with osteosarcoma that has come back (recurrent) or has spread to other places in the body (metastatic). Immunotherapy with monoclonal antibodies, such as atezolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Cabozantinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving atezolizumab and cabozantinib may help to control the osteosarcoma.