Retrospective analysis of risk factors for central nervous system metastases in operable breast cancer: effects of biologic subtype and Ki67 overexpression on survival

Oncology. 2013;84(3):135-40. doi: 10.1159/000345321. Epub 2012 Dec 11.

Abstract

Objective: Identifying factors that predispose patients to central nervous system (CNS) metastases may hasten disease detection and improve treatment outcomes.

Methods: We reviewed the records of patients who were diagnosed with clinical stage I-III primary breast cancer at the National Cancer Center Hospital East from 2003 to 2005. Cox proportional hazard models were fitted to reveal risk factors for CNS metastases.

Results: The median follow-up period after the operation was 53.5 months. Among the 591 identified patients with breast cancer, 76 experienced a relapse. Seventeen patients developed CNS metastases. Multivariate analysis indicated that the triple negative (TN) subtype (hazard ratio = 5.5) and a high Ki67 labeling index (LI; hazard ratio = 3.9) were associated with a higher risk for CNS metastases. At 4 years, the TN subtype was associated with significantly worse overall and disease-free survival rates and a higher cumulative incidence of CNS metastases compared with hormone receptor-positive/ human epidermal growth factor receptor-2-negative tumors. Breast cancers with a Ki67 LI ≥30% were also associated with lower overall and disease-free survival rates and a higher cumulative incidence of CNS metastases compared with cancers with a Ki67 LI <30%.

Conclusion: TN or Ki67-overexpressing breast cancer produced earlier CNS metastases and lower disease-free and overall survival rates.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / metabolism*
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / mortality
  • Brain Neoplasms / secondary*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology*
  • Carcinoma, Ductal, Breast / metabolism
  • Carcinoma, Ductal, Breast / mortality
  • Carcinoma, Ductal, Breast / pathology*
  • Carcinoma, Lobular / metabolism
  • Carcinoma, Lobular / mortality
  • Carcinoma, Lobular / pathology*
  • Female
  • Humans
  • Immunoenzyme Techniques
  • Incidence
  • Ki-67 Antigen / metabolism*
  • Lymphatic Metastasis
  • Middle Aged
  • Neoplasm Staging
  • Prognosis
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism
  • Retrospective Studies
  • Survival Rate
  • Young Adult

Substances

  • Biomarkers, Tumor
  • Ki-67 Antigen
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Receptor, ErbB-2