title: Treatment and prognosis of breast cancer patients with brain metastases according to intrinsic subtype.
abstract: OBJECTIVE
  How breast cancer subtypes should affect treatment decisions for breast cancer patients with brain metastases is unclear. We analyzed local brain metastases treatments and their outcomes according to subtype in patients with breast cancer and brain metastases.
  
  
  METHODS
  We reviewed records and database information for women treated at the National Kyushu Cancer Center between 2001 and 2010. Patients were divided into three breast cancer subtype groups: Luminal (estrogen receptor positive and/or progesterone receptor positive, but human epidermal growth factor receptor 2 negative); human epidermal growth factor receptor 2 positive and triple negative (estrogen receptor negative, progesterone receptor negative and human epidermal growth factor receptor 2 negative).
  
  
  RESULTS
  Of 524 advanced breast cancer patients, we reviewed 65 (12%) with brain metastases and records showing estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status, as well as outcome data; there were 26 (40%) Luminal, 26 (40%) had human epidermal growth factor receptor 2 and 13 (20%) had triple negative subtypes. There was no statistical difference in the number of brain metastases among subtypes; however, rates of stereotactic radiosurgery or surgery for brain metastases differed significantly by subtype (human epidermal growth factor receptor 2: 81%, Luminal: 42% and triple negative: 47%; P = 0.03). Patients having the human epidermal growth factor receptor 2 subtype, a performance status of ≤1 and ≤4 brain metastases, who underwent systemic therapy after brain metastases and underwent stereotactic radiosurgery or surgery, were predicted to have longer overall survival after brain metastases. Multivariate analysis demonstrated that not having systemic therapy and not having the human epidermal growth factor receptor 2 subtype were independent factors associated with an increased risk of death (hazard ratio 2.4, 95% confidence interval 1.01-5.6; P = 0.05 and hazard ratio 2.9, 95% confidence interval 1.5-5.8; P = 0.003, respectively).
  
  
  CONCLUSIONS
  Our study showed that local brain treatments and prognosis differed by subtype in breast cancer patients with brain metastases.
authors.affiliation: Department of Breast Oncology, National Hospital Organization, Kyushu Cancer Center, Fukuoka Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki skuba@nagasaki-u.ac.jp.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Kuba
authors.affiliation: Department of Breast Oncology, National Hospital Organization, Kyushu Cancer Center, Fukuoka.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ishida
authors.affiliation: Department of Breast Oncology, National Hospital Organization, Kyushu Cancer Center, Fukuoka.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki.
authors.forename: Kosho
authors.initials: K
authors.lastname: Yamanouchi
authors.affiliation: Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Minami
authors.affiliation: Department of Pathology, National Hospital Organization, Kyushu Cancer Center, Fukuoka, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Taguchi
authors.affiliation: Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki.
authors.forename: Susumu
authors.initials: S
authors.lastname: Eguchi
authors.affiliation: Department of Breast Oncology, National Hospital Organization, Kyushu Cancer Center, Fukuoka.
authors.forename: Shinji
authors.initials: S
authors.lastname: Ohno
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D001932:Brain Neoplasms / Q000556:secondary* / Q000628:therapy*; D001943:Breast Neoplasms / Q000473:pathology* / Q000628:therapy*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008499:Medical Records; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D016634:Radiosurgery; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D012189:Retrospective Studies; D064726:Triple Negative Breast Neoplasms / Q000473:pathology / Q000628:therapy
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: brain metastasis; breast cancer; prognosis; stereotactic radiosurgery; subtype; whole-brain radiation therapy