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BRCA1 and BRCA2-associated hereditary breast and ovarian cancer

Authors
Beth N Peshkin, MS, CGC
Claudine Isaacs, MD
Section Editors
Anees B Chagpar, MD, MSc, MA, MPH, MBA, FACS, FRCS(C)
Barbara Goff, MD
Don S Dizon, MD, FACP
Deputy Editor
Sadhna R Vora, MD

INTRODUCTION

Most women with breast or ovarian cancer have a sporadic rather than an inherited cancer. About 10 to 20 percent of women with breast cancer have one or more first-degree relatives who are also affected with breast cancer [1,2]. While only 5 to 10 percent of unselected women with breast cancer have a hereditary form, up to 20 percent of women with a family history of breast cancer have a mutation in a major gene, most often in the breast cancer susceptibility genes 1 or 2 (BRCA1 or BRCA2; hereafter, BRCA) [3]. Less frequently, breast or ovarian cancers may be associated with other familial risk syndromes, including Li-Fraumeni and Cowden syndromes. This topic will specifically discuss BRCA mutation-associated cancer risks and related issues. Further discussion of other hereditary breast and ovarian cancer (HBOC) syndromes and gene mutations is covered separately. (See "Overview of hereditary breast and ovarian cancer syndromes".)

In addition, details on the approach to risk assessment, testing, and the management of these patients are discussed separately.

(See "Genetic counseling and testing for hereditary breast and ovarian cancer".)

(See "Management of patients at high risk for breast and ovarian cancer".)

CLINICAL CHARACTERISTICS ASSOCIATED WITH BRCA MUTATIONS

Most hereditary breast and ovarian cancers (HBOC) are due to highly penetrant germline BRCA mutations, which are inherited in an autosomal-dominant fashion. In these patients, there are frequently several generations of women affected with breast cancer (often premenopausal) and, in some families, ovarian cancer as well. In addition, other BRCA-associated malignancies such as prostate, male breast, and pancreatic cancer may be observed. Specific criteria for genetic evaluation in high-risk individuals are discussed elsewhere. (See "Genetic counseling and testing for hereditary breast and ovarian cancer", section on 'Criteria for genetic risk evaluation'.)

                               

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Literature review current through: Nov 2016. | This topic last updated: Mon Apr 04 00:00:00 GMT 2016.
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