Snapshot A 7-year-old boy presents to the pediatric emergency department for lethargy, nausea, and vomiting. Medical history is unremarkable. Physical examination is notable for papilledema and right-sided dysmetria. An MRI brain with and without contrast demonstrates a cerebellar cystic mass. Introduction Overview a slow growing central nervous system (CNS) tumor that arise from astrocytes most frequently arises in the cerebellum but can appear anywhere else in the CNS Epidemiology Incidence most common glial tumor in children ETIOLOGY Pathophysiology exact mechanism unknown but may be due to disrupted cell cycle regulation, leading to abnormal cellular proliferation Associated conditions neurofibromatosis type 1 Presentation Symptoms symptoms of increased intracranial pressure headache nausea vomiting lethargy Physical exam papilledema ataxia (in cerebellar tumors) visual deficits (in optic pathway tumors) Imaging MRI brain with and without contrast indication imaging study of choice findings cystic mass cyst wall enhances in ~50% of cases often has a brightly enhancing mural nodule Studies Histopathology indication confirms the diagnosis obtained via tumor resection or biopsy prognosis degree of atypia (tumor grade) is the best prognostic indicator findings GFAP+ Rosenthal fibers eosinophilic corkscrew fibers Differential Other malignant brain neoplasm differentiating factors based on histological findings e.g., glioblastomas will have pleomorphic tumor cells surrounding a central area of necrosis <table style="font-size: medium; width: 100%; height: 0px;" border="0" cellspacing="0"> <tbody> <tr> <td height="12" bgcolor="#F4F4F4"><strong>Snapshot</strong></td> </tr> <tr> <td> <ul> <li><span style="color: #0000cc;"><span style="font-size: medium;">A</span></span></li> </ul> </td> </tr> <tr> <td height="12" bgcolor="#F4F4F4"><span style="color: #ffffff;"><span style="font-family: Arial, Helvetica, sans-serif; color: #000000; font-size: xx-small;"><span style="font-size: medium;"><strong><span style="font-size: medium;">Introduction</span></strong></span></span></span></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;">Definition </span> <ul> <li><span style="font-size: medium;">a </span> <ul> </ul> </li> </ul> </li> <li><span style="font-size: medium;">Epidemiology </span> <ul> <li><span style="font-size: medium;">i</span></li> </ul> </li> <li><span style="font-size: medium;">Pathophysiology </span> <ul> <li><span style="font-size: medium;">t</span></li> </ul> </li> <li><span style="font-size: medium;">Associated conditions </span> <ul> <li><span style="font-size: medium;">a</span></li> </ul> </li> </ul> </td> </tr> <tr> <td height="12" bgcolor="#F4F4F4"><span style="font-family: Arial, Helvetica, sans-serif; color: #ffffff; font-size: xx-small;"><span style="color: #000000;"><span style="font-size: medium;"><strong><span style="font-size: medium;">Presentation</span></strong></span></span></span></td> </tr> <tr> <td height="10"> <ul> <li><span style="font-size: medium;">Symptoms</span></li> <li><span style="font-size: medium;">Physical exam</span></li> </ul> </td> </tr> <tr style="background-color: #f4f4f4;"> <td><strong><span style="font-size: medium;">Imaging</span></strong></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;"><span style="color: #000000;"><span style="font-size: medium;">M</span></span></span></li> </ul> </td> </tr> <tr style="background-color: #f4f4f4;"> <td><strong><span style="font-size: medium;">Studies</span></strong></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;">A</span></li> </ul> </td> </tr> <tr style="background-color: #f4f4f4;"> <td><strong><span style="font-size: medium;">Differential</span></strong></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;">N</span></li> </ul> </td> </tr> <tr style="background-color: #f4f4f4;"> <td><strong><span style="font-size: medium;">Treatment</span></strong></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;">M</span></li> </ul> </td> </tr> <tr style="background-color: #f4f4f4;"> <td><strong><span style="font-size: medium;">Complications</span></strong></td> </tr> <tr> <td> <ul> <li><span style="font-size: medium;">D<br /></span></li> </ul> </td> </tr> </tbody> </table> differentiating factors based on histological findings e.g., glioblastomas will have pleomorphic tumor cells surrounding a central area of necrosis differentiating factors based on histological findings e.g., glioblastomas will have pleomorphic tumor cells surrounding a central area of necrosis Treatment Surgical resection indication first line in accessible tumors chemotherapy and/or radiation therapy is considered when the tumor is inoperable Complications Leptomeningeal disease spread of the CNS tumor to the leptomeninges (pia and arachnoid mater)