Genetic Counseling: What You Should Know

Jessica Kenney, certified genetic counselor and manager of Catholic Health’s Clinical Genetic Counseling multispecialty program, shares the importance of meeting with a genetic counselor to learn about your risk for developing cancer.

Am I a candidate for genetic counseling?

Anyone can have genetic counseling, but it’s essential for some people. For example, if you don’t know your biological family’s medical history, you should consider genetic counseling to learn if you’re at increased risk.

People diagnosed with solid-tumor cancer and those with a family history of these types of cancer should also consider genetic counseling. 

Additionally, you should consider genetic counseling if you have: 

• A known breast or ovarian cancer gene mutation such as BRCA1 or BRCA2.
• A personal or family history of cancer before age 50.
• A personal or family history of rare cancer such as male breast cancer.
• A personal or family diagnosis of Lynch syndrome-related cancers, including colorectal, endometrial (uterine), ovarian, pancreatic, stomach, or other cancers.
• Cancer in paired organs such as your breasts or kidneys.
• Multiple family members diagnosed with the same or related cancers.
• Multiple new cancers at once.
• Past or current history of colon cancer or multiple colon polyps.
• Past or current history of ovarian cancer.
• Several noncancerous tumors or polyps.

Why do I need genetic counseling?

Every human has cancer genes in their DNA designed to stop cancer cells from growing. 

“They’re called DNA damage repair genes, and they go into action when a person’s DNA is damaged from risk factors like smoking, sun damage or asbestos exposure,” said Jessica.

However, if a gene has a congenital mutation—meaning an abnormality that’s been present since birth—it might not be able to repair the DNA damage before cancer cells start to grow. This is called hereditary predisposition.

That’s why it’s essential to know if you have a hereditary predisposition that increases your risk of developing cancer. Genetic counseling is the first step in discovering your risk. 

What is the genetic counseling process?

The process starts with a one to two-hour consultation with a certified genetic counselor. During the meeting, you and the counselor will discuss your health history and build a family tree going back three generations. If you don't know your family history, your genetic counselor will discuss your options to learn if you carry a genetic variant that increases the risk for cancer.

“The information we discuss during the session will identify patterns of cancer within your family,” said Jessica. “Once we’ve identified those patterns, we help patients decide if they want to pursue genetic testing.”

Genetic testing looks for genetic mutations in a blood or saliva sample. You'll meet with your genetic counselor several weeks after the sample is collected to discuss the results. 

The test results will guide the conversation.

“Genetic counselors serve multiple roles," said Jessica. "We must be able to explain the science while helping patients manage the various emotions that can result from genetic testing.”

Do I have options to reduce my risk?

Your genetic counselor will discuss the results and, if applicable, identify ways to lower your risk of developing cancer. 

The counselor will provide recommendations if there’s a mutation in your DNA. For example, the counselor may recommend more sensitive or more frequent screenings if the mutation is in a gene associated with breast cancer. If it's a high-risk gene, the counselor might recommend surgical removal of breasts.

“Patients are free to make their own decision,” said Jessica. “Genetic counselors are there to provide education, emotional support and referrals to physician specialists.”

How often should I have genetic testing?

Typically genetic testing can be a once-in-a-lifetime event since there is a permanency to our genes. Repeat genetic testing can be obtained for the same indication if new/more genes have been identified to test previously unavailable for testing. You can have genetic testing once or repeated every few years based on research and technological advancements. 

“As science advances, genetic tests are becoming more sensitive to genetic mutations. For example, before 2013, BRCA 1 and 2 were the only known breast cancer genes,” said Jessica.

Researchers have since discovered 10 to 15 more breast cancer genes. Therefore, a repeat genetic test may identify mutations that didn’t appear on previous tests.

Even if you don’t repeat genetic testing, you should meet with your genetic counselor every three to five years to update your medical record and family health history.

What are inherited genetic mutations?

Specific gene mutations can increase the risk of certain types of cancer. Here are a few gene mutations that can be identified through genetic testing. 

ATM. Both men and women carry the ATM gene mutation, which increases the risk of pancreatic, ovarian and breast cancers. The lifetime risk of breast cancer increases by as much as 40%.

BRCA1. BRCA1 mutations increase the risk of breast (65%–85%), ovarian (60%) and second breast cancer (40%) in women. Breast (1.2%) and prostate (26%) cancer in men. Pancreatic (5%) cancer in both genders.

BRCA2. BRCA mutations increase the risk of breast (60%- 80%), ovarian (30%) and second breast cancer (25%) in women. Breast (7%) and prostate (60%) cancer in men. Pancreatic (10%) cancer and melanoma in both genders.

CDHI. This gene mutation increases the risk of lobular breast cancer in women by 40% to 60% and diffuse gastric cancer by 70%in men and 56% in women.

CDK4. A CDK4 mutation increases the lifetime risk of melanoma by as much as 80%. 

PTEN. People with a PTEN mutation have an increased risk of thyroid (35%), breast (85%), endometrial (28%), kidney (34%), colorectal (10%) and melanoma (6%).

STK11. STK11 mutations increase the risk of many types of cancer, including: 

• Breast cancer in women: 54%
• Ovarian cancer: 10%
• Cervical cancer: 10%
• Colorectal cancer: 40%
• Endometrial cancer: 10%
• Lung cancer: 7%
• Pancreatic cancer: 35%
• Small intestine: 15%
• Stomach cancer: 30%
• Testicular cancer: 10%

Catholic Health's genetic counseling services

Genetic counseling is available at St. Francis Hospital & Heart Center® (Roslyn, NY), Good Samaritan University Hospital (West Islip, NY), Mercy Hospital (Rockville Centre, NY) and St. Catherine of Siena Hospital (Smithtown, NY). Your physician can provide a referral. Call your insurance provider for more information.

Learn more about Catholic Health's genetic counseling services. Call 844-86-CANCER (866-993-0638) for more information.