Abstract
Central nervous system leukemia may present in different ways. However, intraparenchymal mass is extremely rare in childhood leukemia. Herein, we report a boy who presented with right hemiparesis and anisocoria 1 year after the cessation of the chemotherapy protocol for acute lymphoblastic leukemia. Cranial imaging demonstrated an extensive mass located in the anterior white matter of left frontal lobe, and cerebrospinal fluid examination revealed concomitant lymphoblasts. Immunohistochemical staining of the biopsy material showed neoplastic cells with positive CD10 and TdT. Complete remission was achieved with chemotherapy alone for a duration of 2 years.