title: Loss of heterozygosity analysis in an anaplastic oligodendroglioma arising after radiation therapy.
abstract: OBJECTIVE
  Oligodendroglial tumors rarely occur after radiation therapy. Here, we report a rare case of anaplastic oligodendroglioma arising after radiation therapy, in which genetic analysis was performed.
  
  
  METHODS
  A 41-year-old man who had received radiation therapy for a tumor of the suprasellar and pineal regions 31 years previously, presented with headache and progressive right hemiparesis. Magnetic resonance (MR) images revealed a ring-enhanced mass lesion in the left frontal lobe. Total removal of the tumor was performed through left frontoparietal craniotomy, and the histologic diagnosis was anaplastic oligodendroglioma. Using 23 microsatellite markers, the allelic status of chromosomes 1p, 10, 17p and 19q was evaluated by a PCR-based loss of heterozygosity (LOH) assay. Markers on chromosomes 1p, 17p and 19q revealed LOH, but none of the markers on chromosome 10 showed LOH. Based on the genetic analysis, this tumor was considered to be sensitive to chemotherapy. Two courses of chemotherapy, with procarbazine, ACNU and vincristine, were performed. However, tumor recurrence was detected only 3 months after the surgery. Despite additional radiochemotherapy, the tumor aggressively increased in size and the patient died with multiple recurrent tumors 1 year after surgery.
  
  
  CONCLUSIONS
  The anaplastic oligodendroglioma presented in this report showed a more aggressive clinical course than was expected from the genetic analysis. The significance of 1p and 19q LOH in radiation-induced oligodendroglial tumors might differ from that in spontaneous counterparts.
authors.affiliation: Department of Neurosurgery, Graduate School of Medical Sciences, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Hata
authors.forename: Tadahisa
authors.initials: T
authors.lastname: Shono
authors.forename: Masahiro
authors.initials: M
authors.lastname: Mizoguchi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Yanlei
authors.initials: Y
authors.lastname: Guan
authors.forename: Shinji
authors.initials: S
authors.lastname: Nagata
authors.forename: Kenshi
authors.initials: K
authors.lastname: Hayashi
authors.forename: Toru
authors.initials: T
authors.lastname: Iwaki
authors.forename: Tomio
authors.initials: T
authors.lastname: Sasaki
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000235:genetics* / Q000503:physiopathology / Q000628:therapy; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics; D017809:Fatal Outcome; D005625:Frontal Lobe / Q000473:pathology* / Q000503:physiopathology / Q000528:radiation effects; D006801:Humans; D019656:Loss of Heterozygosity / Q000235:genetics*; D008279:Magnetic Resonance Imaging; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D009364:Neoplasm Recurrence, Local; D009381:Neoplasms, Radiation-Induced / Q000235:genetics* / Q000503:physiopathology / Q000628:therapy; D009837:Oligodendroglioma / Q000235:genetics* / Q000503:physiopathology / Q000628:therapy; D011237:Predictive Value of Tests; D011878:Radiotherapy / Q000009:adverse effects*; D017211:Treatment Failure
chemical_list: D000970:Antineoplastic Agents