To improve the poor prognosis for children with metastatic osteosarcoma (OS), interleukin-2 (IL-2) was added to the standard treatment due to its capacity to activate lymphocytes and differentiate lymphocyte subsets into lymphokine-activated killer (LAK) cells that are capable of recognizing and killing various tumor cells. This study concerns a cohort of unselected patients aged < 18 years with metastatic OS, who were treated with IL-2, high-dose methotrexate, doxorubicin, cisplatin, ifosfamide, LAK reinfusion, and surgery, between 1995 and 2010. Thirty-five patients aged 4-17 years were involved. Thirty-two of the 35 patients underwent surgery on their primary tumor, and 25 had surgery on lung metastases too. Twenty-seven patients received IL-2 plus LAK reinfusion. The median follow-up was 130 months (77-228), and the 3-year event-free and overall survival rates were 34.3 and 45.0%, respectively. Eleven patients remained alive, all of whom achieved a complete surgical removal of the primary tumor and lung metastases (1 patient did not receive lung resections due to complete lung metastases remission). Patients who had a complete surgical remission of the primary and metastatic sites and who responded well to chemotherapy had a better event-free survival. These results confirm the importance of complete surgical remission and point to a noteworthy (though still be ameliorate) survival rate in our series of patients, underling a potential role for immunotherapy with IL-2 and LAK/NK cell activation.
Keywords: Chemotherapy; Children; IL-2; Lung metastases; Osteosarcoma; Surgery.