title: Clinical Factors for Prognosis and Treatment Guidance of Spinal Cord Astrocytoma.
abstract: METHODS
  Retrospective study.
  
  
  OBJECTIVE
  To obtain information useful in establishing treatment guidelines by evaluating baseline clinical features and treatment outcomes of patients with spinal cord astrocytoma (SCA).
  
  
  BACKGROUND
  The optimal management of SCA remains controversial, and there are no standard guidelines.
  
  
  METHODS
  The study included 20 patients with low-grade and 13 with high-grade SCA surgically treated between 1989 and 2014. Patients were classified according to the extent of surgical resection. Survival was assessed using Kaplan-Meier plots and compared between groups by log-rank tests. Neurological status was defined by the modified McCormick scale and compared between groups by Mann-Whitney U tests.
  
  
  RESULTS
  Surgical resection was performed for 19 of 20 low-grade (95%) and 10 of 13 high-grade (76.9%) SCA patients. Only nine patients (27.3%) underwent gross total resection, all of whom had low-grade SCA. Of all patients, 51.5% showed deteriorated neurological status compared to preoperative baseline. Median overall survival was significantly longer for low-grade SCA than that (91 months, 78% at 5 years vs. 15 months, 31% at 5 years; p=0.007). Low-grade SCA patients benefited from more aggressive resection, whereas high-grade SCA patients did not. Multivariate analysis revealed histology status (hazard ratio [HR], 0.30; 95% confidence interval [CI], 0.09-0.98; p<0.05) and postoperative neurological status (HR, 0.12; CI, 0.02-0.95; p<0.05) as independent predictors of longer overall survival. Adjuvant radiotherapy had no significant impact on survival rate. However, a trend for increased survival was observed with radiation cordotomy (RCT) in high-grade SCA patients.
  
  
  CONCLUSIONS
  Aggressive resection for low-grade and RCT may prolong survival. Preservation of neurological status is an important treatment goal. Given the low incidence of SCA, establishing strong collaborative, interdisciplinary, and multi-institutional study groups is necessary to define optimal treatments.
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Toshitaka
authors: T
authors: Seki
authors: Department of Neurosurgery, Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan.
authors: Kazutoshi
authors: K
authors: Hida
authors: Department of Neurosurgery, Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan.
authors: Shunsuke
authors: S
authors: Yano
authors: Department of Orthopedic Surgery, Teine Keijinkai Hospital, Sapporo, Japan.
authors: Takeshi
authors: T
authors: Aoyama
authors: Department of Neurosurgery, Hokkaido Neurosurgical Memorial Hospital, Sapporo, Japan.
authors: Izumi
authors: I
authors: Koyanagi
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Toru
authors: T
authors: Sasamori
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Shuji
authors: S
authors: Hamauch
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Kiyohiro
authors: K
authors: Houkin
keywords: Astrocytoma; Intramedullary tumor; Outcome; Radiotherapy; Surgery