Cancer genetic risk assessment for individuals at risk of familial breast cancer

 

Abstract

Background

The recognition of an inherited component to breast cancer has led to an increase in demand for information, reassurance, and genetic testing, resulting in the creation of genetics clinics for familial cancer. The first step for patients referred to a cancer genetic clinic is a risk assessment.

Objectives

To evaluate the impact of cancer genetic risk assessment services on patients at risk of familial breast cancer.

Search methods

The specialised register maintained by the Cochrane Breast Cancer Group was searched 16th February 2005. We also searched MEDLINE, EMBASE, CINAHL, PsycLIT, CENTRAL, DARE, ASSIA, Web of Science, SIGLE and LILACS. The searches covered the period 1985 to February 2005. We also hand-searched relevant journals.

Selection criteria

Trials looking at interventions for cancer genetic risk assessment delivery for familial breast cancer were considered for inclusion. Trials assessed outcomes such as understanding of risk, satisfaction and psychological well-being. Studies were excluded if they concerned cancers other than breast cancer or if participants were not at risk of breast cancer. Trials concerning the provision of information or education were also excluded as it was intended to review these separately. Participants could be individuals of any age or gender, with or without a known BRCA mutation, but without a previous history of breast cancer or any other serious illness.

Data collection and analysis

Two authors independently assessed trial quality and extracted data. Additional information was sought from investigators as necessary. Due to the heterogeneity of both the interventions and outcomes, data were analysed descriptively.

Main results

Fifty-eight papers were identified as relevant to the review, 54 of these were subsequently excluded. The three included trials (pertaining to five papers), provide data on 1251 participants and assessed the impact of cancer genetic risk assessment on outcomes including perceived risk, and psychological distress. This review suggests that cancer genetic risk assessment services help to reduce distress, improve the accuracy of the perceived risk of, and increase knowledge about, breast cancer and genetics. The health professional delivering the risk assessment does not appear to have a significant impact on these outcomes.

Authors' conclusions

This review found favourable outcomes for patients' risk assessment for familial breast cancer. However, there were too few papers to make any significant conclusions about how best to deliver cancer genetic risk assessment services. Further research is needed assessing the best means of delivering cancer risk assessment, by different health professionals, in different ways and in alternative locations.

 

Plain language summary

Cancer genetic risk assessment for individuals at risk of familial breast cancer

The recognition of an inherited component to breast cancer has led to an increase in demand for information, reassurance, and genetic testing, resulting in the creation of genetics clinics for familial cancer. Cancer genetic services can involve extended counselling, specialist screening and genetic testing for mutations. Risk assessment is the first step in the process of providing information and support to patients and their families. Information on evidence-based methods of delivering cancer genetic risk assessment services is however sparse. For this review a systematic search, review and assessment of the literature on the delivery of cancer genetic risk assessment services for individuals concerned with familial breast cancer was undertaken.

This review included 3 trials (five papers) which covered the process of risk assessment for familial breast cancer. These focused on the psychosocial impact on patients, as well as other outcomes and aspects of service delivery, and provided data on 1251 participants. Due to the limited amount of trials, this review found insufficient evidence to make any firm conclusions about the best way to deliver risk assessment services for individuals concerned about a family history of breast cancer. All three included studies did however demonstrate improvements in psychological wellbeing and a decrease in the levels of cancer worry as a result of the risk assessment service. Although limited, the findings of this review suggest that cancer genetic risk assessment services can help to reduce distress, improve the accuracy of the individual's perceived risk of, and increase knowledge about, breast cancer and genetics. Existing evidence suggests that such services do not cause patients any harm and, in the short-term, can have a positive effect by helping to ease distress and decrease cancer worry. From this review, the health professional delivering the risk assessment did not appear to have a significant impact on these outcomes.

 

摘要

背景

家族性遺傳乳癌之癌症基因危險評估

要找出可能會導致乳癌的遺傳因子，需要大量的相關資訊、確認與基因檢測，因此出現檢測家族遺傳性癌症之基因門診，到基因門診就診的病人，首先要接受檢測就是危險因子的評估。

目標

評估癌症危險基因篩檢對於家族性乳癌危險群之影響。

搜尋策略

我們會搜尋之範圍涵蓋1985年到2005年2月，有登記並隸屬Cochrane Breast Cancer Group之醫療院所，和MEDLINE、EMBASE、CINAHL、PsycLIT、CENTRAL、DARE、ASSIA、Web of Science、SIGLE和LILACS之電子期刊，並以人工方式搜尋相關紙本期刊。

選擇標準

臨床試驗著重於調查會影響對家族性乳癌進行癌症基因危險評估的各種因素，並對於風險了解、滿意度以及心理之健全等檢驗結果進行評估，本研究會排除不屬於乳癌的癌症與非乳癌危險群之參與者，也不會藉此進行教學或提供研究資訊， 任何年齡、性別，基因型是否具有BRCA變異，都可以參與此臨床試驗，曾罹患乳癌或重大傷病則不具參與資格。

資料收集與分析

評估臨床試驗之品質與數據之獲得係由兩位作者獨立進行，若需要額外資訊，則會再進行調查。因影響評估之因素與試驗結果之間的異質差異，試驗資料以敘述方式分析撰寫。

主要結論

與本評論相關之期刊共58篇，後排除其中之54篇。納入之三次臨床試驗(5篇相關期刊)含括1251位參與者，並分析癌症基因危險評估對病人的危險認知與心理壓力造成之影響。本評論指出，癌症基因危險評估有助於減低壓力、增加病人對乳癌的危險認知和提升遺傳學的知識，而發布危險評估報告的醫療人員則不具有顯著影響。

作者結論

本評論發現家族性乳癌之危險評估對於病人助益良好，然而，相關參考研究有如麟毛鳳角，因此，對於如何提升癌症基因評估的服務，無法提出有具有重大意義的結論。如何使癌症的危險評估能更臻完美，需要由各界之專業醫療人員共同努力。

翻譯人

本摘要由中山醫學大學附設醫院謝明昌翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

家族性遺傳乳癌之癌症基因危險評估: 要找出可能會導致乳癌的遺傳因子，需要大量的相關資訊、重覆確認與基因檢測。癌症基因檢測需要進行大量的諮詢，專業人員測試的和基因突變的篩檢。進行危險評估是提供病人和其家屬評估資訊和支持的第一步。然而，與癌症基因危險評估服務之相關科學資訊則是相當匱乏，而本研究則有系統地查詢，討論和評估有關家族乳癌對個人影響的文獻。本評論包含三組進行家族性乳癌危險評估的臨床試驗(5篇參考文獻)，主要研究對病人心理與社會層面的衝擊，和在各層面影響這項服務的因素，受測者共有1251人。由於臨床試驗的次數和有限的資訊，對於如何以最佳的方式來評估家族乳癌史對於個人的影響，尚不足以提出有重大意義的結論。本篇的三個研究證明，癌症危險評估服務，可以促進心理的健全，提高個人對危險認知的準確度，增進對乳癌和遺傳學的知識，並降低擔心罹癌的焦慮，現有證據指出這項服務並不會對病人造成傷害，就短期而言，對於緩和罹癌焦慮有正面的效果。由本研究來看，進行危險評估報告的醫療人員不對結果有著影響。