Astrocytomas may also start here. Astrocytomas are generally subdivided into high-grade or low-grade tumors. High-grade astrocytomas are the most malignant of all brain tumors.CogniQontrast agent uptake, sometimes in characteristic patterns, can be demonstrated on either CT or MRI-scans in most malignant primary and metastatic brain tumors. This is due to the fact that these tumors disrupt the normal functioning of the blood-brain barrier…