title: Body mass index (BMI): association with clinicopathological factors and outcome of women with newly diagnosed breast cancer in New Zealand.
abstract: OBJECTIVE
  To identify associations of obesity with breast cancer and its outcome in a New Zealand population, including those treated with adjuvant chemotherapy.
  
  
  METHODS
  Data was collated from four regional Breast Cancer Registers, Auckland, Waikato, Wellington and Christchurch, for all women with newly diagnosed breast cancer, with weight and height recorded. Associations of body mass index (BMI) with patient and tumour characteristics, and all-cause mortality were determined.
  
  
  RESULTS
  BMI was available for 5,458 new breast cancers, 27% of all registered. BMI was normal (18.5-24.9kg/m2) for 32.7%, overweight (25-29.9kg/m2) 31.1%, obese (>30kg/m2) 34.9% and 1.3% underweight (<18.5kg/m2). Median age was 55 years. Higher BMI was associated with non-European ethnicity, post-menopausal status, screen-detection, older age and tumours with higher grade, greater size and positive progesterone receptors. Mean survival for women younger than 56 years was 18.0 years for normal BMI and 14.8 years for BMI >35 (p=0.055, Log-rank). Women younger than 56 years treated with adjuvant chemotherapy had lower survival if obese compared with normal BMI (p=0.055, Log-rank).
  
  
  CONCLUSIONS
  High BMI was associated with larger tumours, of higher grade, progesterone receptor positive and post-menopausal status. Obese pre-menopausal women treated with adjuvant chemotherapy had a trend to poorer outcome.
authors.affiliation: Canterbury Regional Cancer and Haematology Centre, Christchurch Hospital, Christchurch, Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Medicine, University of Otago, Christchurch.
authors.forename: Bridget
authors.initials: B
authors.lastname: Robinson
authors.affiliation: Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Pathology, University of Otago, Christchurch.
authors.forename: Margaret
authors.initials: M
authors.lastname: Currie
authors.affiliation: Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Pathology, University of Otago, Christchurch.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Phillips
authors.affiliation: Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Pathology, University of Otago, Christchurch.
authors.forename: Gabi
authors.initials: G
authors.lastname: Dachs
authors.affiliation: Canterbury Regional Cancer and Haematology Centre, Christchurch Hospital, Christchurch, Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Medicine, University of Otago, Christchurch.
authors.forename: Matthew
authors.initials: M
authors.lastname: Strother
authors.affiliation: Mackenzie Cancer Research Group, University of Otago Christchurch, Department of Pathology, University of Otago, Christchurch, Cancer Society Tissue Bank, Department of Pathology, University of Otago, Christchurch.
authors.forename: Helen
authors.initials: H
authors.lastname: Morrin
authors.affiliation: Department of Surgery, Christchurch Hospital, Christchurch.
authors.forename: Val
authors.initials: V
authors.lastname: Davey
authors.affiliation: Department of Medicine, University of Otago, Christchurch.
authors.forename: Chris
authors.initials: C
authors.lastname: Frampton
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D015897:Comorbidity; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D009765:Obesity / Q000453:epidemiology*; D015995:Prevalence; D016896:Treatment Outcome