title: Ethnicity and outcome of young breast cancer patients in the United Kingdom: the POSH study.
abstract: BACKGROUND
  Black ethnic groups have a higher breast cancer mortality than Whites. American studies have identified variations in tumour biology and unequal health-care access as causative factors. We compared tumour pathology, treatment and outcomes in three ethnic groups in young breast cancer patients treated in the United Kingdom.
  
  
  METHODS
  Women aged ≤ 40 years at breast cancer diagnosis were recruited to the POSH national cohort study (MREC: 00/06/69). Personal characteristics, tumour pathology and treatment data were collected at diagnosis. Follow-up data were collected annually. Overall survival (OS) and distant relapse-free survival (DRFS) were assessed using Kaplan-Meier curves, and multivariate analyses were performed using Cox regression.
  
  
  RESULTS
  Ethnicity data were available for 2915 patients including 2690 (91.0%) Whites, 118 (4.0%) Blacks and 87 (2.9%) Asians. Median tumour diameter at presentation was greater in Blacks than Whites (26.0 mm vs 22.0 mm, P=0.0103), and multifocal tumours were more frequent in both Blacks (43.4%) and Asians (37.0%) than Whites (28.9%). ER/PR/HER2-negative tumours were significantly more frequent in Blacks (26.1%) than Whites (18.6%, P=0.043). Use of chemotherapy was similarly high in all ethnic groups (89% B vs 88.6% W vs 89.7% A). A 5-year DRFS was significantly lower in Blacks than Asians (62.8% B vs 77.0% A, P=0.0473) or Whites (62.8 B% vs 77.0% W, P=0.0053) and a 5-year OS for Black patients, 71.1% (95% CI: 61.0-79.1%), was significantly lower than that of Whites (82.4%, 95% CI: 80.8-83.9%, W vs B: P=0.0160). In multivariate analysis, Black ethnicity had an effect on DRFS in oestrogen receptor (ER)-positive patients that is independent of body mass index, tumour size, grade or nodal status, HR: 1.60 (95% CI: 1.03-2.47, P=0.035).
  
  
  CONCLUSIONS
  Despite equal access to health care, young Black women in the United Kingdom have a significantly poorer outcome than White patients. Black ethnicity is an independent risk factor for reduced DRFS particularly in ER-positive patients.
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: E
authors.initials: E
authors.lastname: Copson
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: T
authors.initials: T
authors.lastname: Maishman
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: S
authors.initials: S
authors.lastname: Gerty
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: B
authors.initials: B
authors.lastname: Eccles
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: L
authors.initials: L
authors.lastname: Stanton
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: R I
authors.initials: RI
authors.lastname: Cutress
authors.affiliation: Centre for Statistics in Medicine, Wolfson College Annexe, Oxford OX2 6UD, UK.
authors.forename: D G
authors.initials: DG
authors.lastname: Altman
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: L
authors.initials: L
authors.lastname: Durcan
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: P
authors.initials: P
authors.lastname: Simmonds
authors.affiliation: Tumour Biology Department, Institute of Cancer, Barts & The London School of Medicine & Dentistry, Charterhouse Square, London, EC1M 6BQ, UK.
authors.forename: L
authors.initials: L
authors.lastname: Jones
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: W
authors.initials: W
authors.lastname: Tapper
authors.affiliation: Cancer Sciences Academic Unit and University of Southampton Clinical Trials Unit, Faculty of Medicine, University of Southampton and University Hospital Southampton Foundation Trust, Tremona Road, Southampton SO16 6YA, UK.
authors.forename: Diana
authors.initials: D
authors.lastname: Eccles
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000208:ethnology* / Q000473:pathology / Q000628:therapy*; D015331:Cohort Studies; D005260:Female; D006297:Health Services Accessibility; D006801:Humans; D011446:Prospective Studies; D016896:Treatment Outcome; D006113:United Kingdom / Q000453:epidemiology