Maintenance treatment with interferon-gamma and low-dose cyclophosphamide for pediatric high-grade glioma

Background The prognosis of high-grade glioma in children is poor. Purpose Interferon-gamma may increase the immune surveillance of glioma cells. Earlier clinical evidence had shown that low dose cyclophosphamide (CPM) increased immune response. Methods After induction treatment with simultaneous radiation and chemotherapy, patients were treated with individually increasing interferon-gamma (IFN-y) doses starting from 25 μg/m 2 /d s.c. increasing up to a maximum of 175 μg/m 2 /d within 7 weeks. Cyclophosphamide was given at 300 mg/m 2 i.v. every 21 days. Forty pediatric glioma patients were enrolled (median age: 8.5 year, male: n = 22). Tumor locations included cerebral cortex (n = 8), basal ganglia (n = 4), brainstem (n = 24), cerebellum (n = 3), spinal cord (n = 1). Histologies were GBM (n = 14), AA (n = 14), LGG (n = 2, diffuse intrinsic pontine glioma). There was grade IV toxicity for thrombocytopenia (10%) and leucopenia (2.5%), grade III toxicity for central nervous (2.5%) and hepatic (5%) side effects, no toxic death. The observation time of the six surviving patients was: 1.2, 1.9, 4.2, 4.4, 4.6 and 4.7 years respectively. The median overall survival (1 year) was not significantly different from a historical control group (0.8 years). The survival of pontine gliomas appeared even inferior when compared to the previous protocol (n.s.). Conclusion Maintenance treatment with IFN-y and low dose CPM has no sufficient beneficial effect for the treatment of high-grade glioma.