Review article
Systematic review of the empirical investigation of resources to support decision-making regarding BRCA1 and BRCA2 genetic testing in women with breast cancer

https://doi.org/10.1016/j.pec.2017.11.016Get rights and content

Highlights

  • Few resources available to support genetic testing decision-making in breast cancer.

  • Resources to support decision-making for BRCA testing are endorsed by patients.

  • Existing tools increase knowledge/understanding of hereditary breast cancer.

  • New tools should include functionalities to support the decision-making process.

Abstract

Objective

Identify existing resources developed and/or evaluated empirically in the published literature designed to support women with breast cancer making decisions regarding genetic testing for BRCA1/2 mutations.

Methods

Systematic review of seven electronic databases. Studies were included if they described or evaluated resources that were designed to support women with breast cancer in making a decision to have genetic counselling or testing for familial breast cancer. Outcome and process evaluations, using any type of study design, as well as articles reporting the development of decision aids, were eligible for inclusion.

Results

Total of 9 publications, describing 6 resources were identified. Resources were effective at increasing knowledge or understanding of hereditary breast cancer. Satisfaction with resources was high. There was no evidence that any resource increased distress, worry or decisional conflict. Few resources included active functionalities for example, values-based exercises, to support decision-making.

Conclusion

Tailored resources supporting decision-making may be helpful and valued by patients and increase knowledge of hereditary breast cancer, without causing additional distress.

Practice implications

Clinicians should provide supportive written information to patients where it is available. However, there is a need for robustly developed decision tools to support decision-making around genetic testing in women with breast cancer.

Introduction

Traditionally, genetic testing for women diagnosed with breast cancer has been offered within specialist services. The focus of provision has been on those with a family history and usually after completion of active treatment. Several factors are influencing the increasing number and nature of referrals for genetic testing. Technological advances mean testing is becoming cheaper and faster. It is also recognised that a substantial proportion of women with no family history of breast cancer, but who have other increased-risk features (including younger age at breast cancer diagnosis, certain ethnicities, tumour characteristics) may carry a BRCA1 or BRCA2 (hereafter BRCA1/2) mutation. This has resulted in changes to the threshold for referral to genetic services [1]. Additionally, while considerable international variation exists, testing for germline mutations at the time of cancer diagnosis to inform treatment decisions (treatment-focused genetic testing – TFGT) is becoming more common. Knowledge of BRCA mutation status is increasingly used or requested to support decision-making between breast conserving surgery versus mastectomy and/or contralateral mastectomy. The advantages and disadvantages of combining treatment of the primary cancer with that of future risk of the developing a second new primary can then be considered [1].

There is also evidence of increased public awareness of inherited predisposition to breast cancer and more referrals for genetic counselling following wide media coverage of preventative surgeries of actress Angelina Jolie (BRCA1 positive and with a family history of breast and ovarian cancer) [[2], [3]]. Finally, the advent of targeted drug therapies [4] means more breast cancer specialists are recommending genetic testing to their patients to inform the choice of chemotherapy regimens and inclusion in clinical trials.

The result is a trend towards ‘mainstreaming’ of genetic testing; with the ambition of offering testing for BRCA1/2 as part of routine patient care for young women diagnosed with breast cancer. It is therefore imperative that women are supported to make an informed choice about genetic testing given the likely short timeframes following diagnosis [5]. Women diagnosed at a younger age (≤50 years) represent a group for whom treatment decisions can be particularly complex; for example, they may consider risk-reducing surgery in the context of concerns about adverse impacts on fertility, sexual functioning, body image and self-esteem [6]. In a busy oncology clinic, the time and knowledge base to adequately inform women about the pros and cons of genetic testing is often limited.

Empirically evaluated decision support interventions (or decision aids) have been found to increase knowledge and result in patients feeling better informed and clearer about what matters most to them when making medical treatment and screening choices [7]. Decision aids aim to supplement clinical consultations and help patients make considered choices. They clearly state the decision to be made and the options available with associated benefits and harms. They also include components that allow patients to recognise their values associated with the decision being made [8]. This is different to educational materials that describe the health condition and options but do not attempt to support patient contributions to the decision-making process [7]. Similar resources have been developed for women with breast cancer choosing between breast conserving surgery and mastectomy [9] and women at high-risk of developing breast and/or ovarian cancer making decisions about genetic testing [10]. Decision support tools could be particularly valuable in the context of decision-making for TFGT, where there is increased pressure to compress specialist genetic counselling into the timeframe required for the treatment of the primary cancer.

This systematic review therefore aimed to identify existing resources developed and/or evaluated empirically in the published literature designed to support women’s decision-making regarding genetic testing for BRCA1/2 mutations. This was the first phase of a study, which set out to develop such a decision support tool for young women recently diagnosed with breast cancer. This is in line with the Medical Research Council guidelines for developing and evaluating complex interventions, which recommends identification of the relevant existing evidence base, ideally by way of a systematic review as a first stage of intervention development [11]. The objectives of the review are threefold: to characterise published resources, assess their acceptability and evaluate their impact. As well as informing intervention development, this evidence synthesis will serve to generate new research questions in line with clinical priorities and make practice recommendations on the basis of current evidence.

Section snippets

Methods

Guidance from the Centre for Reviews and Dissemination [12] and the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement [13] informed the methods for conducting and reporting this review.

Results

Fig. 1 shows the flow of studies in this review. A total of 3595 publications were identified (after removal of duplications). On inspection of titles and abstracts, 3434 publications were excluded, and 2 full texts were unobtainable. Full texts were examined for 162 articles and 9 met the criteria for final inclusion [[18], [19], [20], [21], [22], [23], [24], [25]]. Rahman et al. [21] was a conference abstract detailing a study reported in full in Quinn et al. [26]. The 9 references identified

Discussion

This systematic review set out to identify resources in the published literature designed to support decision-making around genetic testing for BRCA1/2 mutations. The format, content and purpose varied across studies, though all studies included some paper-based information. All publications that provided an evaluation of the resource describe gains in knowledge or understanding of hereditary breast cancer.

No publications described negative impact on distress, anxiety or decisional conflict as

Practice implications and research recommendations

This systematic review reveals that tailored resources to support decision-making may be helpful and valued by patients and increase knowledge of hereditary breast cancer, without causing additional distress or anxiety. We therefore suggest clinicians provide supportive written information to patients where it is available. However, provision of such evidence-based resources is limited and is not keeping pace with clinical advances and increase in demand for genetic counselling and testing

Contributions

Claire Foster and Diana Eccles are joint chief investigators of this Breast Cancer Now Funded project, they made substantial contributions to the conception of the systematic review design, critically revising the article and approved the final version for submission, CF also contributed to title screening.

Chloe Grimmett contributed to the conception of the systematic review, study selection, data extraction and synthesis, interpretation of the data, drafted the article and approved the final

Funding

Funded by Breast Cancer Now: 2014 May PR270. The funder had no involvement in the study design, preparation or submission of the manuscript.

Conflict of interest

The authors declare that there is no conflict of interest.

Acknowledgements

With thanks to Shelly Mason, Lesley Turner, Munaza Ahmed, and Dr Bryony Eccles, members of the advisory team.

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