Fig. 4

a Histologic features of tumor resection from left posterior frontal lobe of Case 2. Anaplastic pleomorphic xanthoastrocytoma composed of epithelioid glial cells with minimal pleomorphism (A) (H&E, 200x). Anaplastic features include less pleomorphism than is typical for low grade PXA, areas of necrosis (not pictured), and increased proliferation evidenced by Ki67 (B) (Immunohistochemistry for Ki67, 200x). b. Immunohistochemistry of case 2 tumor and frontal cortex control. The staining shows strong nuclear and cytoplasmic reactivity with mild increase in the staining in patient tumor cells