title: Women's preferences for contralateral prophylactic mastectomy following unilateral breast cancer: What risk-reduction makes it worthwhile?
abstract: OBJECTIVE
  Contralateral prophylactic mastectomy (CPM) reduces the risk of contralateral breast cancer (BC) following unilateral BC, but may not increase survival in BRCA1/2 mutation negative women. Despite this, and the risk for adverse physical and psychological impact, uptake is increasing in BRCA1/2 mutation negative women. We aimed to quantify the degree of reduction in lifetime contralateral BC risk women required to justify CPM, and to explore demographic, disease and psychosocial predictors of preferences using Protection Motivation Theory (PMT) as a theoretical framework. Reasoning behind preferences was also examined.
  
  
  METHODS
  388 women previously diagnosed with unilateral BC, of negative or unknown BRCA1/2 status, were recruited from an advocacy group research database. Two hypothetical risk trade-off scenarios were used to quantify the reduction in lifetime contralateral BC risk that women judged necessary to justify CPM, using a 5% and 20% baseline. Demographic, disease and PMT measures were assessed using a questionnaire.
  
  
  RESULTS
  Most women required their risk to be more than halved from a 5% or 20% baseline to justify CPM. Polarised preferences were also common, with some women consistently accepting or refusing CPM independent of risk/benefit trade-offs. Preferences were associated with coping self-efficacy and having a prior CPM. Explanations for judging CPM worthwhile included reducing or eliminating contralateral BC risk, attaining breast symmetry and reducing worry.
  
  
  CONCLUSIONS
  Risk-reduction preferences were highly variable. Decisive factors in women's preferences for CPM related to clinical, psychological and cosmetic outcomes, but not to demographic or disease characteristics.
authors.affiliation: School of Psychology, The University of Sydney, NSW, Australia; Psycho-Oncology Co-operative Research Group (PoCoG), The University of Sydney, NSW, Australia. Electronic address: stephanie.tesson@sydney.edu.au.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Tesson
authors.affiliation: School of Psychology, The University of Sydney, NSW, Australia.
authors.forename: Imogen
authors.initials: I
authors.lastname: Richards
authors.affiliation: Department of Oncology, Auckland Hospital, Auckland, New Zealand.
authors.forename: David
authors.initials: D
authors.lastname: Porter
authors.affiliation: Division of Cancer Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Department of Oncology, Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, VIC, Australia; Centre for Epidemiology and Biostatistics, The University of Melbourne, Melbourne, VIC, Australia; Department of Medicine, St Vincent's Hospital, The University of Melbourne, Melbourne, VIC, Australia.
authors.forename: Kelly-Anne
authors.initials: KA
authors.lastname: Phillips
authors.affiliation: Sydney Catalyst Cancer Translational Cancer Centre, The University of Sydney, NSW, Australia.
authors.forename: Nicole
authors.initials: N
authors.lastname: Rankin
authors.affiliation: Pain Management Research Institute, The University of Sydney at Royal North Shore Hospital, St Leonards, NSW, Australia.
authors.forename: Daniel
authors.initials: D
authors.lastname: Costa
authors.affiliation: University of Western Australia, Perth, WA, Australia.
authors.forename: Toni
authors.initials: T
authors.lastname: Musiello
authors.affiliation: Breast Cancer Network Australia (BCNA), Melbourne, VIC, Australia.
authors.forename: Michelle
authors.initials: M
authors.lastname: Marven
authors.affiliation: Psycho-Oncology Co-operative Research Group (PoCoG), The University of Sydney, NSW, Australia; Centre for Medical Psychology and Evidence-based Decision-making (CeMPED), The University of Sydney, NSW, Australia.
authors.forename: Phyllis
authors.initials: P
authors.lastname: Butow
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001007:Anxiety / Q000209:etiology / Q000517:prevention & control; D001943:Breast Neoplasms / Q000517:prevention & control* / Q000523:psychology* / Q000601:surgery; D003657:Decision Making; D005260:Female; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D057240:Patient Preference; D000072036:Prophylactic Mastectomy / Q000523:psychology*; D011582:Psychological Theory; D018570:Risk Assessment; D020377:Self Efficacy; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Breast cancer; Contralateral breast cancer; Contralateral prophylactic mastectomy; Decision-making; Patient preferences