Prognostic factors for stereotactic radiosurgery-treated patients with cerebral metastasis: implications on randomised control trial design and inter-institutional collaboration

Eur J Cancer. 2014 Apr;50(6):1148-58. doi: 10.1016/j.ejca.2014.01.001. Epub 2014 Feb 12.

Abstract

Introduction: Defining key prognostic factors for patients with cerebral metastases who underwent stereotactic radiosurgery (SRS) treatment will greatly facilitate future clinical trial designs.

Methods: We adopted a two-phase study design where results from one cohort were validated in a second independent cohort. The exploratory analysis reviewed the survival outcomes of 1017 consecutive patients (with 3610 metastases) who underwent Gamma radiosurgery at the University of California, San Diego (UCSD)/San Diego Gamma Knife Center (SDGKC). Multivariate analysis was performed to identify prognostic factors. Results were validated using data derived from 2519 consecutive patients (with 17,498 metastases) treated with SRS at the Katsuta Hospital.

Results: For the SDGKC cohort, the median overall survival of patients following SRS was 7 months. Two year follow-up data were available for 85% of the patients. Multivariate analysis found that patient age, Karnofsky Performance Status, systemic cancer status, tumour histology, number of metastasis and cumulative tumour volume independently associated with overall survival (p<0.001). All statistical associations were validated by multivariate analysis of data derived from the Katsuta Hospital cohort.

Conclusions: This is the first integrated study that defined prognostic factors for SRS-treated patients with cerebral metastases using an inter-institutional validation study design. The work establishes a model for collaborative interactions between large volume centers and provides prognostic variables that should be incorporated into future clinical trial design.

Keywords: Brain metastases; Cumulative tumour volume; Prognostic factors; Randomised clinical trial design; Stereotactic radiosurgery.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Neoplasms / secondary*
  • Brain Neoplasms / surgery*
  • Cohort Studies
  • Cooperative Behavior
  • Female
  • Follow-Up Studies
  • Humans
  • Kaplan-Meier Estimate
  • Karnofsky Performance Status
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Outcome Assessment, Health Care / methods*
  • Patient Care Team
  • Prognosis
  • Radiosurgery / methods*
  • Randomized Controlled Trials as Topic / methods
  • Tumor Burden
  • Young Adult