Absence of enhancement in a lesion does not preclude primary central nervous system T-cell lymphoma: A case report

Figure 4 The immunohistochemical staining test results. A: Hematoxylin & eosin stain (× 40) shows scattered lymphocyte infiltration in the specimen; B: Cluster of differentiation (CD)3 immunostain (× 40); C: CD8 immunostain (× 40), CD3 and CD8 positive lymphocytes suggests T-cell infiltration; D: CD20 immunostain (× 40), CD20 positive cells suggest presence of an immune response, likely towards the neoplastic cells; E: CD68 immunostain (× 40), CD68 positive microglia suggests an ongoing response to an injury or pathology in the brain; F: Antigen Kiel-67 (KI-67) immunostain (× 40), KI-67 index of 40% indicates the presence of high proliferation rate. Overall, these findings suggest a high proliferation neoplastic disorder involving lymphoid cells.