Background: Metronomic chemotherapy (MC) consists of the administration of a low dose of chemotherapy on a daily or weekly basis without a long break to achieve an antitumoral effect through an antiangiogenic effect or stimulation of the immune system. The potential effect of MC with continuous oral cyclophosphamide and methotrexate in patients with high-grade operable osteosarcomas (OSTs) of the extremities was investigated.
Methods: Patients with high-grade OSTs who were 30 years old or younger were eligible for registration at diagnosis.