Risk reduction strategies in familial breast and ovarian cancer — ASN Events

Risk reduction strategies in familial breast and ovarian cancer (#15)

Melanie Wuttke 1 , Kelly-Anne Phillips 1 2 3 4
  1. Division of Cancer Medicine, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  2. Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
  3. Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Victoria, Australia
  4. Department of Medicine, St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia

Aims/Background

This review explores the current evidence-base for, and national uptake of, risk reducing surgery and medications in women at high risk for breast and ovarian cancer, focussing particularly on women with BRCA1 & BRCA2 mutations. Uptake of risk-reducing salpingo-oophorectomy & tamoxifen is lower than might be considered optimal and the reasons for this are complex.

Methods
A review of the literature published between 2013 – June 2014 was performed and findings integrated with existing knowledge.

Results
Prophylactic bilateral mastectomy (BM) and bilateral salpingo-oophorectomy (BSO) are effective surgical strategies for managing risk, and are associated with risk reductions of over 90% for breast and ovarian cancer, respectively [1]. BSO also reduces breast cancer incidence by 50% if performed prior to age 40 [1]. Risk reducing medications, including tamoxifen & anastrozole, administered daily for 5 years reduce breast cancer risk substantially & for tamoxifen the benefits persist for at least 10 years [2, 3]. Breast cancer surveillance mammography &, in certain cases, magnetic resonance imaging are recommended to attempt to detect a cancer at a favourable stage when cure is achievable.

Rates of uptake are around 38% for BSO, 21% for BM and 3% for chemoprevention [4]. Women are more likely to utilise risk reducing interventions based on their family experience of breast and ovarian cancer, have children, are married, have a greater perceived risk of cancer and a lower educational level [5][6]. Barriers to chemoprevention use include not being told about it as an option, concerns regarding side effects, experiences of friends & family on medication & the daily reminder of cancer risk [7].

Conclusion
Women at high risk of breast & ovarian cancer have a range of effective options available for reducing their risk, however, uptake is suboptimal. Continued counselling & support is pivotal in guiding a woman’s decision making process.

  1. Domchek, S.M., et al., Association of risk-reducing surgery in BRCA1 or BRCA2 mutation carriers with cancer risk and mortality. JAMA, 2010. 304(9): p. 967-75.
  2. Cuzick, J., et al., Anastrozole for prevention of breast cancer in high-risk postmenopausal women (IBIS-II): an international, double-blind, randomised placebo-controlled trial. Lancet, 2014. 383(9922): p. 1041-8.
  3. Cuzick, J., et al., Selective oestrogen receptor modulators in prevention of breast cancer: an updated meta-analysis of individual participant data. Lancet, 2013. 381(9880): p. 1827-34.
  4. Collins, I.M., et al., Preventing breast and ovarian cancers in high-risk BRCA1 and BRCA2 mutation carriers. Med J Aust, 2013. 199(10): p. 680-3.
  5. Singh, K., et al., Impact of family history on choosing risk-reducing surgery among BRCA mutation carriers. Am J Obstet Gynecol, 2013. 208(4): p. 329 e1-6.
  6. Collins, I.M., et al., Preventing Breast and Ovarian Cancer in Women at Highest Risk; Long-term Follow-up of Participants in the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer (kConFab). Data unpublished.
  7. Donnelly, L.S., et al., Uptake of Tamoxifen in consecutive premenopausal women under surveillance in a high-risk breast cancer clinic. BJC. 2014. 110:1681-1687.
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