title: A Systematic Review of Clinical Outcomes and Prognostic Factors for Patients Undergoing Surgery for Spinal Metastases Secondary to Breast Cancer.
abstract: METHODS
  Review of the literature.
  
  
  OBJECTIVE
  Surgery and cement augmentation procedures are effective palliative treatment of symptomatic spinal metastases. Our objective is to systematically review the literature to describe the survival, prognostic factors, and clinical outcomes of surgery and cement augmentation procedures for breast cancer metastases to the spine.
  
  
  METHODS
  We performed a literature review using PubMed to identify articles that reported outcomes and/or prognostic factors of the breast cancer patient population with spinal metastases treated with any surgical technique since 1990.
  
  
  RESULTS
  The median postoperative survival for metastatic breast cancer was 21.7 months (8.2 to 36 months), the mean rate of any pain improvement was 92.9% (76 to 100%), the mean rate of neurologic improvement was 63.8% (53 to 100%), the mean rate of neurologic decline was 4.1% (0 to 8%), and the local tumor control rate was 92.6% (89 to 100%). Kyphoplasty studies reported a high rate of pain control in selected patients. Negative prognostic variables included hormonal (estrogen and progesterone) and human epidermal growth factor receptor 2 (HER2) receptor refractory tumor status, high degree of axillary lymph node involvement, and short disease-free interval (DFI). All other clinical or prognostic parameters were of low or insufficient strength.
  
  
  CONCLUSIONS
  With respect to clinical outcomes, surgery consistently yielded neurologic improvements in patients presenting with a deficit with a minimal risk of worsening; however, negative prognostic factors associated with shorter survival following surgery include estrogen receptor/progesterone receptor negativity, HER2 negativity, and a short DFI.
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Sciubba
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: C Rory
authors.initials: CR
authors.lastname: Goodwin
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: Alp
authors.initials: A
authors.lastname: Yurter
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: Derek
authors.initials: D
authors.lastname: Ju
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: Ziya L
authors.initials: ZL
authors.lastname: Gokaslan
authors.affiliation: Division of Spine, Department of Orthopaedics, University of British Columbia and Vancouver General Hospital, Vancouver, British Columbia, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Fisher
authors.affiliation: Department of Neurosurgery, University of Texas MD Anderson Cancer Center, Houston, Texas, United States.
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Rhines
authors.affiliation: Division of Neurosurgery and Spinal Program, Department of Surgery, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Fehlings
authors.affiliation: Division of Neurosurgery, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Fourney
authors.affiliation: Department of Neurological Surgery, The James Comprehensive Cancer Center and The Wexner Medical Center at the Ohio State University, Columbus, Ohio, United States.
authors.forename: Ehud
authors.initials: E
authors.lastname: Mendel
authors.affiliation: Department of Neurological Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York, United States.
authors.forename: Ilya
authors.initials: I
authors.lastname: Laufer
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
authors.forename: Chetan
authors.initials: C
authors.lastname: Bettegowda
authors.affiliation: Sarcoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, United States.
authors.forename: Shreyaskumar R
authors.initials: SR
authors.lastname: Patel
authors.affiliation: Division of Orthopaedic Surgery, Department of Surgery, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada.
authors.forename: Y Raja
authors.initials: YR
authors.lastname: Rampersaud
authors.affiliation: Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Arjun
authors.initials: A
authors.lastname: Sahgal
authors.affiliation: Spinal Division, Oxford University Hospital NHS Trust, Oxford, United Kingdom.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Reynolds
authors.affiliation: Department of Neurological Surgery, University of California San Francisco, San Francisco, California, United States.
authors.forename: Dean
authors.initials: D
authors.lastname: Chou
authors.affiliation: Division of Orthopaedic Surgery, McGill University, Montreal, Quebec, Canada.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Weber
authors.affiliation: Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Michelle J
authors.initials: MJ
authors.lastname: Clarke
keywords: breast cancer; kyphoplasty; metastasis; spine; surgery; survival; tumor; vertebroplasty