Genetics and Cancer: Are You at Risk?

“When breast cancer is detected early, in the localized stage, the 5-year survival rate is 98%” (National Cancer Institute)

© G. Parong 2006

Recently, there has been a lot of attention being given to genetic testing (also referred to as a carrier screening test) ever since movie actor, Angelina Jolie (whose mother died of ovarian cancer), having tested positive for the BRCA1 mutation, took a bold step by undergoing an elective double mastectomy in hopes of preventing any future incidence of the disease. Since then, much media focus has centered on genetic testing, leading many women to take a serious look into such testing to uncover their own biological predisposition to genetically linked diseases.

In 2013, the American Cancer Society’s estimates:

• About 232,340 new cases of invasive breast cancer will be diagnosed in women.
• About 64,640 new cases of carcinoma in situ (CIS) will be diagnosed (CIS is non-invasive and is the earliest form of breast cancer).
• About 39,620 women will die from breast cancer

Breast cancer is the second leading cause of cancer death in women, exceeded only by lung cancer. The chance that breast cancer will be responsible for a woman’s death is about 1 in 36 (about 3%). Death rates from breast cancer have been declining since about 1989, with larger decreases in women younger than 50. These decreases are believed to be the result of earlier detection through screening and increased awareness, as well as improved treatment.

Approximately 7% of breast cancer and 11 – 15% of ovarian cancer cases are caused by mutations in the BRCA1 or BRCA2 genes. When someone carries a mutation in either of these genes, they have a syndrome called Hereditary Breast and Ovarian Cancer (HBOC) syndrome. Myriad offers testing to determine whether a patient is a carrier of the BRCA1 or BRCA2 gene mutations. When assessing the risk of carrying these mutations a patient’s personal and family history is collected to investigate the risk for HBOC. Once a patient is identified as being at increased risk of HBOC, genetic test results provide the most accurate means of cancer risk assessment for a patient. (see table 1)

The American Cancer Society estimates for ovarian cancer in the United States for 2013 are:

• About 22,240 women will receive a new diagnosis of ovarian cancer.
• About 14,230 women will die from ovarian cancer.

Ovarian cancer is the ninth most common cancer among women, excluding non-melanoma skin cancers. It ranks fifth in cancer deaths among women, accounting for more deaths than any other cancer of the female reproductive system. Ovarian cancer accounts for about 3% of all cancers in women. A woman’s risk of getting ovarian cancer during her lifetime is about 1 in 72. Her lifetime chance of dying from ovarian cancer is about 1 in 100. (These statistics don’t count low malignant potential ovarian tumors.) This cancer mainly develops in older women. About half of the women who are diagnosed with ovarian cancer are 63 years or older. It is more common in white women that African-American women. The rate at which women are diagnosed with ovarian cancer has been slowly falling over the past 20 years.

Approximately 11 – 15% of ovarian cancer and 7% of breast cancer cases are caused by mutations in the BRCA1 or BRCA2 genes. When someone carries a mutation in either of these genes, they have a syndrome called Hereditary Breast and Ovarian Cancer (HBOC) syndrome.1,2,3 Myriad offers testing to determine whether a patient is a carrier of the BRCA1 or BRCA2 gene mutations. When assessing the risk of carrying these mutations a patient’s personal and family history is collected to investigate the risk for HBOC. Once a patient is identified as being at increased risk of HBOC, genetic test results provide the most accurate means of cancer risk assessment for a patient. (see Table 1)

Table 1

In the United States, cancer of the endometrium is the most common cancer of the female reproductive organs. The American Cancer Society estimates for endometrial cancer in the United States for 2013 are:

• About 49,560 new cases of cancer of the body of the uterus (uterine corpus) will be diagnosed.
• About 8,190 women will die from cancers of the uterine body.

These estimates include both endometrial cancers and uterine sarcomas. About 2% of uterine body cancers are sarcomas, so the actual numbers for endometrial cancer cases and deaths are slightly lower than these estimates. Endometrial cancer is rare in women under the age of 40. Most cases are found in women aged 50 and over, with more than half of all endometrial cancer cases diagnosed in the 50 to 69 age group. The average chance of a woman being diagnosed with this cancer during her lifetime is about one in 38. There are over 500,000 women who are survivors of this cancer. This cancer is more common in white women, but black women are more likely to die from it. (American Cancer Society).

Hereditary Uterine (Endometrial) Cancer

Table 2

About 3% to 5% of colorectal cancers are believed to be caused by mutations in the MLH1, MSH2, MSH6, PMS2, or EPCAM genes.40 When someone carries a mutation in any of these genes, they have a syndrome called Lynch syndrome. Lynch syndrome is also calledHereditary Non-polyposis Colorectal Cancer syndrome (HNPCC). (see Table 2 above)

People with Lynch syndrome are at higher risk of developing several different types of cancer, including:

• Colorectal cancer
• Uterine (Endometrial) cancer
• Ovarian cancer
• Stomach cancer
• And rarely, urinary/renal, pelvis, biliary tract, small bowel, pancreas, and brain cancers

Some patients may also develop sebaceous adenomas, a non-cancerous tumor of an oil-producing gland.

An individual with, or a family history† of, any of the following:

• Breast cancer before 50
• Ovarian cancer at any age
• Two primary breast cancers in an individual at any age
• Both breast and ovarian cancer in an individual at any age
• Male breast cancer, any age
• Triple negative breast cancer, any age
• Ashkenazi Jewish descent with Hereditary Breast and Ovarian Cancer (HBOC) syndrome-associated cancer, any age‡
• Three or more HBOC syndrome-associated cancers at any age‡
• Colorectal cancer before 50
• Endometrial cancer before 50
• Two or more Lynch syndrome cancers§, any age
• A previously identified BRCA or Lynch syndrome mutation in the family

* Assessment criteria based on medical society guidelines. For these individual medical society guidelines, go to www.MyriadPro.com/guidelines.
† Family members include first-, second-, and third-degree blood relatives on both your mother and father’s sides.
‡ HBOC syndrome-associated cancers include breast (including ductile carcinoma in situ [DCIS]), ovarian, pancreatic, and aggressive prostate cancers.
§ Lynch syndrome-associated cancers include colon/rectal, uterine/endometrial, ovarian, stomach/gastric, kidney/urinary tract, biliary tract, small bowel, pancreas, brain, and sebaceous adenoma cancers.

We offer a new genetic test from Myriad Genetics, called“myRisk™”. This “panel” test determines whether you are a carrier of any one of the gene mutations discussed above. When assessing the risk of carrying these mutations, your personal and family history are collected to investigate the risk for breast cancer, or uterine cancer (Lynch syndrome). If you have any indicators for being at increased risk for these cancers, our genetic tests can provide the most accurate means of cancer risk assessment. To find out if you are genetically at risk for any of these cancers, go through the following questionnaires, then take our Hereditary Cancer Quiz. If you find indicators that you may be at risk, call us to schedule an appointment to be tested or book your appointment online.

Breast Cancer

 About Myriad myRisk™

Myriad myRisk™ Hereditary Cancer is a scientific advancement revolutionizing hereditary cancer testing. Blending both genetic test status AND personal cancer family history, Myriad myRisk represents the next generation of hereditary cancer risk testing. Myriad myRisk identifies elevated risk for 8 important cancers by analyzing multiple, clinically actionable genes. Additionally, Myriad myRisk provides a summary of available medical society guidelines to help you optimize your patients’ medical management.

Approximately 5% to 10% of all cancers develop because a person inherits a gene that is broken (mutated) in a way that allows cancer to grow. Individuals with these broken genes are far more likely to develop cancer, often at a much earlier age, than the general population. That’s why being tested with myRisk is so important.

This is the only hereditary cancer test that provides information about your risk and management based on both your personal/ family cancer history and your genetic results.

The experts at Myriad, who have tested more than one million patients over 15 years, have the knowledge and experience to bring genetic results and personal and family cancer history together into one fully integrated, personalized report.

Regardless of the results, you and your healthcare provider will benefit from the knowledge and insight the test provides. Knowing whether you are positive (you have a broken gene) or negative (you do not) enables you and your healthcare provider to create a personal health management plan.

It is not uncommon for cancer to “run in the family” when there is no genetic evidence of hereditary cancer. If this is the case for you, you might still have a higher risk than the general population. Your healthcare provider may want you to have screening tests more often so you can be monitored more closely. It is also important that you share your test status with your family so that they can follow up with their own healthcare providers to determine their risk.

If your result is positive, there are many ways to manage your cancer risk. Understanding the information in your report is the first step. The report your healthcare provider receives will include information about the broken gene itself and your personal and family cancer history, both of which may increase the risk for specific cancers. The myRisk™ test report will also give your healthcare provider management recommendations based on medical societies’ guidelines. Knowing what you are dealing with makes management plans more focused.

Dr. Tam may review your test report with you. Make sure all your questions are answered, and take the time you need to fully understand your results. Don’t hesitate to call Dr. Tam if you think of questions at a later time.

Take our Hereditary Cancer Quiz here. Your results will be returned to Dr. Tam and, together, you both can determine if genetic testing would beneficial to you.

If you would like to speak personally with Dr. Tam or undergo any of these tests, book your appointment online or call us to make your appointment today.