<prompt> Tl-weighted axial gadolinium-enhanced MRI demonstrates an enhancing tumor of the right frontal lobe. The most likely diagnosis isOligodendrogliomaEpendymomaPCNSLGlioblastoma multiforme  <response>: D Glioblastoma multiforme On MRI, the tumors appear as ring-enhancing masses with central necrosis and surrounding edema. Glioblastoma multiforme GBM; malignant glioma is the highest-grade form of astrocytoma and makes up about two thirds of all brain astrocytomas. Prognosis for this tumor is at the extreme worst end because of its high-grade status. 