Inhaled Granulocyte-Macrophage Colony Stimulating Factor for First Pulmonary Recurrence of Osteosarcoma: Effects on Disease-Free Survival and Immunomodulation. A Report From the Children's Oncology Group

Purpose: Osteosarcoma most commonly recurs in the lung. Based on preliminary data on the antitumor effects of granulocyte-macrophage colony stimulating factor (GM-CSF) in animal models, and promising phase I trials, we embarked on a feasibility study of inhaled GM-CSF in patients with first isolated pulmonary recurrence of osteosarcoma. Experimental Design: Forty-three eligible patients received inhaled GM-CSF at doses from 250 to 1,750 mu g twice daily on alternate weeks. Following two cycles, patients underwent thoracotomy to resect tumor and analyze pulmonary nodules for expression of Fas/Fas ligand (Fas/FasL), and the presence of dendritic cells by immunostaining for CD1a, clusterin, and S100. Following surgery, patients received 12 additional cycles of therapy on alternating weeks or until progression. Event-free survival and survival, and feasibility of therapy delivery were evaluated. Results: Dose escalation to 1,750 mu g twice daily was feasible with no dose-limiting toxicity. Mean scores for Fas/FasL in nodules from patients with bilateral recurrence who underwent unilateral thoracotomy pretreatment (using a scoring system of 0-3) were 1.3 and 0.88, respectively, compared with 0.78 and 0.62 in nodules resected following two cycles of therapy. Only 11 of 30 nodules postinhalation were positive for CD1a, 4 of 30 for S100, and 6 of 30 for clusterin. Event-free and overall survival at 3 years were 7.8% and 35.4%, respectively. Conclusions: Inhalation of GM-CSF at doses from 250 to 1,750 mu g twice daily on alternate weeks was feasible with low toxicity. However, no detectable immunostimulatory effect in pulmonary metastases or improved outcome postrelapse was seen. Clin Cancer Res; 16(15); 4024-30. (C) 2010 AACR.