LG-18TWO CASES REPORT OF INFANTILE PILOMYXOID ASTROCYTOMA

Abstract

Introduction: Pilomyxoid astrocytoma (PMA) is rare pediatric astrocytic tumor, which is variant of pilocytic astrocytoma (PA).PMAis dominated by a markedly mucoid matrix, monomorphous bipolar cells, and a predominantly angiocentric call arrangement. We reported two PMA patients who treated in our institute. CASE 1: 6-month-old girl presented poor weight gain.MRIshoweda hypothalamic homogeneously enhanced mass. She underwent partial resection of the tumor and diagnosed PMA. Following tumor resection, chemotherapy with CDDP (0.7mg/m2)/CBDCA (175mg/m2) and VCR (1.5mg/m2) was given. Although the chemotherapy was given, the tumor was progression. Reoperation and gannma-knife surgery was performed for the recurrent tumor and tumor is regression now. CASE 2: 6-year-old girl presented headache and vomiting cased by the hydrocephalus. MRI showed chiasmatic homogeneously enhanced mass extending third ventricle. She underwent partial resection of the tumor and diagnosed PMA. Following tumor resection, chemotherapy with CBDCA (550mg/m2) and VCR (1.5mg/m2) was given, and the tumor is stable now. DISCUSSION: PMA is classified as a variant of PA in the WHO classification of CNS tumors. PMA is substantially shorter PFS and OS than typical PA, although PMAand PA are noted to show similar expression phenotypes on immunohistochemistry. Theclinical courseofPAandPMAis not yetunderstood well, so it is necessary to observe these clinical courses well.