Cancer Genetics Risk Assessment and Counseling (PDQ®)–Health Professional Version

Executive Summary

This executive summary reviews the topics covered in this PDQ summary on cancer genetics risk assessment and genetic counseling, with hyperlinks to detailed sections below that describe the evidence on each topic.

Identification of Individuals for Cancer Genetics Risk Assessment and Counseling
Individuals are considered to be candidates for cancer risk assessment if they have a personal and/or family history (on the maternal or paternal side) or clinical characteristics with features suggestive of hereditary cancer. These features vary by type of cancer and specific hereditary syndrome. Criteria have been published to help identify individuals who may benefit from genetic counseling. It is important that individuals who are candidates for genetic testing undergo genetic education and counseling before testing to facilitate informed decision-making and adaptation to the risk or condition. Genetic education and counseling allows individuals to consider the various medical uncertainties, diagnosis, or medical management options based on varied test results; and the risks, benefits, and limitations of genetic testing.
Components of Cancer Genetics Risk Assessment and Counseling
Comprehensive cancer risk assessment and counseling is a consultative service that includes clinical assessment, genetic testing when appropriate, and risk management recommendations delivered in the context of one or more genetic counseling sessions. Pretest genetic counseling is an important part of the risk assessment process and helps patients understand their genetic testing options and potential outcomes. Posttest genetic counseling helps patients understand their test results, including the medical implications for themselves and their relatives.
The recommended provision of cancer risk assessment services optimally involves care providers from multiple disciplines, including a genetic counselor; a genetics advanced practice nurse; a medical geneticist or a physician, such as an oncologist, surgeon, or internist; and potential referrals to other specialists, such as mental health professionals, endocrinologists, and reproductive specialists.
Traditionally, genetic counseling services have been delivered using individualized, in-person appointments. However, other methodologies are being explored, including group sessions, telephone counseling, and telemedicine by videoconferencing.
Genetic Testing Considerations
There are many factors that can influence an individual’s decision to undergo genetic testing and which type of test to use, including the presence of a known pathogenic variant in the family, patterns of cancer in the family, insurance coverage, family planning considerations, and the psychological impact of a test result. Previously, most germline genetic testing was offered for a single gene at a time; however, recent technological advances have resulted in the widespread availability of multigene (panel) testing, which can simultaneously test for pathogenic variants in many genes at once, often at costs comparable to single-gene testing. Research examining the use of multigene testing is under way. Some genetic tests are also offered directly to the consumer (DTC). While these tests may promote patient autonomy and increased awareness of the importance of family history, DTC genetic testing may not include genetic counseling or interpretation of the results by a genetics professional.
Ethical, Legal, and Social Implications
Having an understanding of the ethical, legal, and social implications regarding cancer genetic testing may influence the clinician’s response to the complex questions and issues that may arise during the process of risk assessment and counseling. The tenets of beneficence, nonmaleficence, autonomy, and justice are part of a framework needed to balance the complex and potentially conflicting factors surrounding a clinician’s role in respecting privacy, confidentiality, and fair use of genetic information obtained from cancer genetic testing.
Employment and insurance discrimination are common concerns for individuals considering genetic testing. The Genetic Information Nondiscrimination Act, a Federal law passed in 2008, protects the provision of health insurance and employment discrimination on the basis of genetics information; however, it does not apply to members of the military or to long-term care insurance.

Introduction

[Note: Many of the medical and scientific terms used in this summary are found in the NCI Dictionary of Genetics Terms. When a linked term is clicked, the definition will appear in a separate window.]

[Note: A concerted effort is being made within the genetics community to shift terminology used to describe genetic variation. The shift is to use the term “variant” rather than the term “mutation” to describe a difference that exists between the person or group being studied and the reference sequence. Variants can then be further classified as benign (harmless), likely benign, of uncertain significance, likely pathogenic, or pathogenic (disease causing). Throughout this summary, we will use the term pathogenic variant to describe a disease-causing mutation. Refer to the Cancer Genetics Overview summary for more information about variant classification.]

This summary describes current approaches to assessing and counseling people about their chance of having an inherited susceptibility to cancer. Genetic counseling is defined by the National Society of Genetic Counselors as the process of helping people understand and adapt to the medical, psychological, and familial implications of genetic contributions to disease. Several reviews present overviews of the cancer risk assessment, counseling, and genetic testing process.[1,2]

Individuals are considered to be candidates for cancer risk assessment if they have a personal and/or family history (maternal or paternal lineage) with features suggestive of hereditary cancer.[1] These features vary by type of cancer and specific hereditary syndrome. Criteria have been published to help identify individuals who may benefit from genetic counseling.[1,3] The PDQ cancer genetics information summaries on breast, ovarian, endometrial, colorectal, prostate, kidney, and skin cancers and endocrine and neuroendocrine neoplasias describe the clinical features of hereditary syndromes associated with these conditions.

The following are features that suggest hereditary cancer:[4-8]

Unusually early age of cancer onset (e.g., premenopausal breast cancer).
Multiple primary cancers in a single individual (e.g., colorectal and endometrial cancer).
Bilateral cancer in paired organs or multifocal disease (e.g., bilateral breast cancer or multifocal renal cancer).
Clustering of the same type of cancer in close relatives (e.g., mother, daughter, and sisters with breast cancer).
Cancers occurring in multiple generations of a family (i.e., autosomal dominant inheritance).
Occurrence of rare tumors (e.g., retinoblastoma, adrenocortical carcinoma, granulosa cell tumor of the ovary, ocular melanoma, or duodenal cancer).
Occurrence of epithelial ovarian, fallopian tube, or primary peritoneal cancer.
Unusual presentation of cancer (e.g., male breast cancer).
Uncommon tumor histology (e.g., medullary thyroid carcinoma).
Rare cancers associated with birth defects (e.g., Wilms tumor and genitourinary abnormalities).
Geographic or ethnic populations known to be at high risk of hereditary cancers. Genetic testing candidates may be identified based solely on ethnicity when a strong founder effect is present in a given population (e.g., Ashkenazi heritage and BRCA1/BRCA2 pathogenic variants).

As part of the process of genetic education and counseling, genetic testing may be considered when the following factors are present:[9-11]

An individual's personal history (including ethnicity) and/or family history are suspicious for a genetic predisposition to cancer.
The genetic test has sufficient sensitivity and specificity to be interpreted.
The test will impact the individual's diagnosis, cancer management or cancer risk management, and/or help clarify risk in family members.

It is important that individuals who are candidates for genetic testing undergo genetic education and counseling before testing to facilitate informed decision making and adaptation to the risk or condition.[1,7-13] Genetic education and counseling allows individuals to consider the various medical uncertainties, diagnosis, or medical management based on varied test results, and the risks, benefits, and limitations of genetic testing.

References

Riley BD, Culver JO, Skrzynia C, et al.: Essential elements of genetic cancer risk assessment, counseling, and testing: updated recommendations of the National Society of Genetic Counselors. J Genet Couns 21 (2): 151-61, 2012. [PUBMED Abstract]
Weitzel JN, Blazer KR, MacDonald DJ, et al.: Genetics, genomics, and cancer risk assessment: State of the Art and Future Directions in the Era of Personalized Medicine. CA Cancer J Clin 61 (5): 327-59, 2011 Sep-Oct. [PUBMED Abstract]
Hampel H, Bennett RL, Buchanan A, et al.: A practice guideline from the American College of Medical Genetics and Genomics and the National Society of Genetic Counselors: referral indications for cancer predisposition assessment. Genet Med 17 (1): 70-87, 2015. [PUBMED Abstract]
Tobias DH, Eng C, McCurdy LD, et al.: Founder BRCA 1 and 2 mutations among a consecutive series of Ashkenazi Jewish ovarian cancer patients. Gynecol Oncol 78 (2): 148-51, 2000. [PUBMED Abstract]
Beller U, Halle D, Catane R, et al.: High frequency of BRCA1 and BRCA2 germline mutations in Ashkenazi Jewish ovarian cancer patients, regardless of family history. Gynecol Oncol 67 (2): 123-6, 1997. [PUBMED Abstract]
Gabai-Kapara E, Lahad A, Kaufman B, et al.: Population-based screening for breast and ovarian cancer risk due to BRCA1 and BRCA2. Proc Natl Acad Sci U S A 111 (39): 14205-10, 2014. [PUBMED Abstract]
Randall LM, Pothuri B, Swisher EM, et al.: Multi-disciplinary summit on genetics services for women with gynecologic cancers: A Society of Gynecologic Oncology White Paper. Gynecol Oncol 146 (2): 217-224, 2017. [PUBMED Abstract]
Committee on Practice Bulletins–Gynecology, Committee on Genetics, Society of Gynecologic Oncology: Practice Bulletin No 182: Hereditary Breast and Ovarian Cancer Syndrome. Obstet Gynecol 130 (3): e110-e126, 2017. [PUBMED Abstract]
Robson ME, Storm CD, Weitzel J, et al.: American Society of Clinical Oncology policy statement update: genetic and genomic testing for cancer susceptibility. J Clin Oncol 28 (5): 893-901, 2010. [PUBMED Abstract]
Lancaster JM, Powell CB, Chen LM, et al.: Society of Gynecologic Oncology statement on risk assessment for inherited gynecologic cancer predispositions. Gynecol Oncol 136 (1): 3-7, 2015. [PUBMED Abstract]
Robson ME, Bradbury AR, Arun B, et al.: American Society of Clinical Oncology Policy Statement Update: Genetic and Genomic Testing for Cancer Susceptibility. J Clin Oncol 33 (31): 3660-7, 2015. [PUBMED Abstract]
National Comprehensive Cancer Network: NCCN Clinical Practice Guidelines in Oncology: Genetic/Familial High-Risk Assessment: Breast and Ovarian. Version 3.2019. Plymouth Meeting, Pa: National Comprehensive Cancer Network, 2019. Available online with free registration.Exit Disclaimer Last accessed June 20, 2019.
National Comprehensive Cancer Network: NCCN Clinical Practice Guidelines in Oncology: Genetic/Familial High-Risk Assessment: Colorectal. Version 1.2019. Plymouth Meeting, PA: National Comprehensive Cancer Network, 2019. Available online with free registration.Exit Disclaimer Last accessed July 19, 2019.