A 25-year-old man presented with new seizure disorder, and was found to have multiple enhancing lesions in the brain, spinal cord, none (vertebral column) and liver. The photos are taken from a resected left temporal lobe brain tumor. Figures 1~3 are from frozen section (HE) at magnification 10x, 20x and 40x. Figures 4~8 are from HE-stained paraffin section at magnification 4x, 10x, 20x, 40x and 60x. What are your differential diagnoses? What further workup do you suggest?