title: Adjuvant radiotherapy delays recurrence following subtotal resection of spinal cord ependymomas.
abstract: BACKGROUND
  Ependymoma is the most common glial tumor of the adult spinal cord. Current consensus recommends surgical resection with gross total resection (GTR) whenever possible. We performed a comprehensive review of the literature to evaluate whether adjuvant radiotherapy after subtotal resection (STR) has any benefit.
  
  
  METHODS
  A PubMed search was performed to identify adult patients with spinal cord ependymoma who underwent surgical resection. Only patients who had clearly defined extent of resection with or without adjuvant radiotherapy were included for analysis. Kaplan-Meier and multivariate Cox regression survival analyses were performed to determine the effects of adjuvant radiotherapy on progression-free survival (PFS) and overall survival (OS).
  
  
  RESULTS
  A total of 348 patients underwent surgical resection of spinal cord ependymomas, where GTR was obtained in 77.0% (268/348) of patients. Among those who received STR, 58.8% (47/80) received adjuvant radiotherapy. PFS was significantly prolonged among those who received adjuvant radiotherapy after STR (log rank; P < .001). This prolonged PFS with adjuvant radiotherapy remained significant in multivariate Cox regression analysis (STR versus STR + RT group; hazard ratio (HR) = 2.26, P = .047). By contrast, improved OS was only associated with GTR (GTR versus STR + RT group; HR = 0.07, P = .001) and benign ependymomas (HR = 0.16, P = .001).
  
  
  CONCLUSIONS
  Surgery remains the mainstay treatment for spinal cord ependymomas, where GTR provides optimal outcomes with longest PFS and OS. Adjuvant radiotherapy prolongs PFS after STR significantly, and OS is improved by GTR and benign tumor grade only.
authors.affiliation: Department of Neurological Surgery, University of California at San Francisco, 505 Parnassus Ave, San Francisco, CA 94117, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Oh
authors.forename: Michael E
authors.initials: ME
authors.lastname: Ivan
authors.forename: Matthew Z
authors.initials: MZ
authors.lastname: Sun
authors.forename: Gurvinder
authors.initials: G
authors.lastname: Kaur
authors.forename: Michael
authors.initials: M
authors.lastname: Safaee
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Kim
authors.forename: Eli T
authors.initials: ET
authors.lastname: Sayegh
authors.forename: Derick
authors.initials: D
authors.lastname: Aranda
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Parsa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003131:Combined Modality Therapy; D004806:Ependymoma / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D019635:Neurosurgical Procedures; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D013120:Spinal Cord Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D015996:Survival Rate; D055815:Young Adult