Breast and Ovarian Cancer Clinical Guidelines - Purpose
The intent of these Clinical Guidelines is to assist the health professional to provide optimal care to patients and families considering the complex and often challenging issues associated with risk assessment, counseling and testing for genetic susceptibility to breast and ovarian cancer. The Guidelines were produced under the auspices of the Professional Practice and Guidelines Committee of the American College of Medical Genetics, with the participation of representatives of various medical and allied health primary care and specialty organizations. These included oncologists, obstetrician/gynecologists, surgeons, family practitioners, internists, radiologists, clinical geneticists, genetic counselors, oncology nurses, and advocacy group members [see Section G for a complete listing of the represented groups and Section H for Biosketches of all participants]. Funding for the project was provided through a grant from the New York State Department of Health to the American College of Medical Genetics Foundation, the educational and research arm of the College. The Guidelines are divided into the following sections: (A) Purpose; (B) Guidelines, Algorithm and Questionnaire; (C)Executive Summary; (D) Guidelines Justification; (E) References; (F) Signatories; (G) Represented Societies; and (H) Biosketches. Appendices I-XIV follow. This abbreviated version of the document is being widely circulated. The entire document, with complete references, justification section and appendices is available upon request.
Breast and ovarian cancer contribute significantly to morbidity and mortality among women. Breast cancer is the most common cancer in American women; approximately 180,000 cases are diagnosed annually and nearly 44,000 die of this disease each year. It is estimated that 10 - 12% of American women will develop breast cancer during their lifetimes. There are at present about 2 million breast cancer survivors in the U.S. While ovarian cancer is less common, with an annual incidence of approximately 27,000 and a 1.8% lifetime risk for American women, this malignancy is more difficult to detect and treat, thus accounting for approximately 14,000 deaths per year.
The vast majority of cases of breast cancer do not show a strong familial tendency and appear to be sporadic. It is now estimated that only 5-10% of cases of breast cancer are due to identifiable genetic factors. Although this document alludes to environmental and hormonal factors which also may contribute to risk for these malignancies (such as age at menarche, parity, hormone supplementation, etc.) risk assessment as discussed here is limited to genetic risk assessment. Environmental and hormonal factors which may increase risk are discussed only briefly, although these factors may interact with genetic status in as yet undetermined ways.
Genetic testing for susceptibility to breast and ovarian cancer has been highlighted in both the electronic and print media and extensively covered in the medical literature since the identification of two independent genes (BRCA1 in 1994 and BRCA2 in 1995) which predispose to these malignancies. A significant proportion of heritable cases of breast and/or ovarian cancer involves mutations in either of these two genes. It is anticipated that future discoveries will disclose additional genes associated with these cancers. These breakthrough findings have raised public expectations for enhanced early detection and prevention of morbidity and mortality in both the individual patient and in the population at large. Most recently, commercial interests have begun marketing widespread testing of these two genes, fostering public interest and placing physicians under pressure to provide such services.
The health care professional who offers DNA testing for breast/ovarian cancer genetic susceptibility must assure that the patient participates in a multi-step process, including risk assessment, pre-test education, and post-test counseling. Unfortunately, scientific data needed at each point in the decision-making process (re: genetic testing) are not complete and current methods of early detection and treatment are imperfect. For instance, accurate risk figures are not yet available for the age-specific and lifetime risks for cancer for each of the more than 300 mutations detected to date in both BRCA1 and BRCA2. The complete array of clinical features associated with each specific mutation is not yet described. Data on success rates and risks associated with individual prevention and early detection strategies are also lacking. Without such information, exact cancer risk calculations can not be made, nor can specific outcomes be predicted. In spite of these critical limitations, guidance is clearly needed for clinicians at this dynamic juncture, in order to avoid inappropriate use of genetic testing and to prevent unnecessary anxieties and costs for patients, their families, and their health care providers.
The recommendations in these Guidelines are based on data from the current literature (citations provided in section E) and/or on a consensus of opinion of those experts participating in this effort. The information herein should help the interested provider to incorporate rational risk assessment methods and management strategies into current practice. The potential benefits, as well as the burdens and risks, of genetic testing in this area are reviewed.
The Guidelines have been prepared to help the primary care provider to participate in the pre- and post-test education and counseling required for every patient contemplating genetic testing for breast and ovarian cancer. Although some important genetic, epidemiological, and clinical issues remain unresolved, it is essential that all health care providers understand the familial basis of some cancers and the potential applications of genetic testing as part of the risk assessment process. The Guidelines do not comment on who should provide the counseling, nor try to demarcate where risk assessment leaves off and genetic counseling begins. It is hoped that the enhanced collaborative relationships encouraged in the Guidelines will improve quality of care provided to all patients.
Where to go for help:
- See Apendices IX and X.
- Contact the NYS Genetic Services Program at (phone) 518-474-1222 or (fax) 518-473-1733.
- Call the National Cancer Institute at 1-800-4CANCER to access a list of practitioners specializing in the area of cancer genetics, or contact them by Email: http://cancernet.nci.hlh.gov/wwwprot/genetic/genesrch.shtml.
Some providers may opt to handle all components identified in the Guidelines themselves; others will choose to refer all patients identified as being at increased risk to an individual with special expertise in cancer genetics. Still others may opt to provide the pretest education only, and refer those found to be mutation positive to specialists for more comprehensive post-test counseling. Each of these alternatives is appropriate, as long as the comprehensive package of services, in the aggregate, is provided.
Complex family histories may be encountered in the course of risk assessment;
for instance, some families may exhibit multiple cases of malignancies involving various organs other than, or in addition to, breast and/or ovary, which may or may not represent a hereditary cancer syndrome. In such cases, consultation with colleagues specializing in cancer genetics is especially important. Health professionals in NYS specializing in the hereditary aspects of cancer are listed in Appendix IX. A list of State Genetics Coordinators is included as Appendix X; these individuals can provide access to cancer genetics specialists in their states.
The critical aspect for the primary care provider is to recognize individuals from families where increased risk for hereditary predisposition may exist so that patients can be offered appropriate options. Those choosing to refer should prepare their patient for the counseling visit(s) and should help her or him to understand and incorporate the genetic counseling information provided. These Guidelines and the Justification and Appendices that follow are presented with awareness of the many gaps in current knowledge and the dynamic nature of this rapidly evolving area. It is expected that utilization of these Guidelines will help to reduce the morbidity and mortality associated with these conditions and to avoid inappropriate, costly and unnecessary genetic testing.
