Metronomic antiangiogenic therapy in children with recurrent brain tumours of different histologies

Children with relapsed malignant brain tumours have a poor prognosis despite intensive treatment including high-dose chemotherapy with stem cell rescue [1, 2]. Angiogenesis, the formation of new blood vessels, is an important component of normal physiological processes such as wound healing and development. Moreover, tumour growth and metastasis is closely related to formation of new blood vessels [3, 4]. Antiangiogenic therapy inhibits neovascularization, thereby inhibiting tumour progression indirectly [5]. The term metronomic chemotherapy refers to the chronic administration of chemotherapeutic agents at relatively low, minimally toxic doses, and without prolonged drug-free breaks. Beside the antiangiogenic effect, metronomic chemotherapy has been shown to modulate anti-tumoural immunity and has the ability to induce tumour dormancy [6]. The combination of agents used in our metronomic antiangiogenic therapy is based on a four-drug regimen (thalidomide, celecoxib, etoposide and cyclophosphamide) published by Kieran et al. in 2005 [7]. We augmented this regimen with bevacizumab, fenofibrate, and intrathecal therapy with the goal to improve progression-free survival for patients with recurrent or refractory CNS tumours for whom no curative therapy is available. We report on our experience with an antiangiogenic metronomic chemotherapy for paediatric patients with recurrent CNS tumours of different histologies.