title: Clinico-pathological features of pilomyxoid astrocytoma of the optic pathway.
abstract: Five cases of pilomyxoid astrocytoma (PmA) characterized by a monophasic pattern with a myxoid background were selected for a clinicopathological study from 23 cases previously diagnosed as pilocytic astrocytoma (PA). All PmA patients were either infants or young children (mean age 2.1 years), and all tumors were located in the optic chiasm/hypothalamus region. All cases received chemotherapy, which reduced tumor size, and the location of the tumor became confined to the optic chiasm. In two cases, tumor recurrence occurred 3 and 7 years after chemotherapy. Histology of the recurrent tumors showed the biphasic pattern of classical PA. Hence, we conclude that PmA might be an infantile form of PA and speculate that a subset of PmA in the optic pathway/hypothalamus originates from the optic chiasm, possibly derived from radial glia existing in the embryonic optic chiasm.
authors.affiliation: Laboratory of Molecular and Cellular Pathology, Hokkaido University School of Medicine, Kita 15, Nishi 7, 060-8638, Kita-ku, Sapporo, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Chikai
authors.forename: Akiko
authors.initials: A
authors.lastname: Ohnishi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kato
authors.forename: Jun
authors.initials: J
authors.lastname: Ikeda
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Sawamura
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Iwasaki
authors.forename: Tomoo
authors.initials: T
authors.lastname: Itoh
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Sawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Nagashima
mesh_terms: D001254:Astrocytoma / Q000473:pathology* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D004358:Drug Therapy; D005260:Female; D006801:Humans; D007029:Hypothalamic Neoplasms / Q000473:pathology* / Q000628:therapy; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009897:Optic Chiasm / Q000473:pathology*; D019574:Optic Nerve Neoplasms / Q000473:pathology* / Q000628:therapy; D013194:Staining and Labeling; D013997:Time Factors