What are infiltrative/diffuse gliomas?

➢ Preferentially affect the cerebral hemispheres ➢ Whatever their initial grade, they progress inexorably towards higher grade lesions. ➢On the basis of histologic features, astrocytomas are stratified into three groups: diffuse astrocytoma (grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV), with increasingly grim prognosis as the grade increases. ➢ These lesions do not metastasize to other organs such as the liver or lungs ➢ They can exceptionally give intra-axial metastases (intrarachidian dissemination in the CSF) or along the peripheral nerves. ➢The identification of certain molecular alterations makes it possible to better define the tumor process and its prognosis