The value of anti-angiogenics in primary brain tumor therapy

Abstract

Glioblastoma Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults. The current standard treatment is tumor resection followed by adjuvant radiotherapy and concomitant chemotherapy with temozolomide. Even with this intensive and multimodal approach, the prognosis remains poor with a median survival of 14-16 months. Glioblastomas are strongly vascularized tumors that frequently contain pathological and dysfunctioning blood vessels. Thus, angiogenesis inhibitors have been investigated increasingly and become a promising treatment approach. The most common anti-angiogenic agent bevacizumab was approved by the United States Food and Drug Administration as monotherapy in relapsed glioblastoma patients in 2009. However, despite promising preclinical data and early clinical trials, anti-angiogenic therapy has failed to show a survival benefit in randomized controlled trials. Anaplastic Oligodendroglial Tumors Similar to GBM therapy, the treatment of recurrent anaplastic oligodendroglial tumors is also challenging with only partially effective therapeutic options and modalities. In comparison to glioblastomas, only very limited data exist regarding the activity of anti-angiogenic compounds in recurrent anaplastic gliomas. Meningioma Meningioma is another common central nervous system tumor in adults with mostly benign, localized, and noninvasive character. However, some meningiomas tend to be more aggressive with limited therapeutic options in case of recurrence or progression. Preclinical studies are scarce; however, data from few prospective clinical trials suggest a possible role for anti-angiogenic treatment. The aim of this chapter is to review preclinical and clinical trial data of anti-angiogenic therapy in the above mentioned as well as in further less common brain tumors.