Do you need genetic testing for breast cancer?

Being able to identify if you’re at increased risk for breast cancer because of family history is powerful.

You’ve seen reports about women with a family history of breast cancer choosing preventive surgery to significantly reduce their breast cancer risk. Since your grandmother, mom or sister has had breast cancer, it’s got you wondering: Do you need genetic testing to find out if you’re more likely to develop the disease?

 

“Being able to identify if you’re at increased risk for breast cancer because of family history is powerful,” says Banu Arun, M.D., professor in Breast Medical Oncology and Clinical Cancer Prevention, and co-medical director of Clinical Cancer Genetics at MD Anderson. “If your chances for developing the disease are higher, you have options to reduce those chances by up to 95%,” Arun says.

 

Yet, most cancer cases aren’t related to family history. “Only about 5 to 10% of cancer cases are related to genetics,” Arun says. This means that genes linked to cancer pass from one blood relative to another.

 

Below, Arun shares the information you need to decide if genetic testing for breast cancer is right for you.

 

Know your family’s cancer history

 

You can start to understand your risk for inherited breast cancer by mapping your family’s cancer history.

 

Check for these factors to determine if you may be at risk:

 

You had breast cancer before age 50.

You had high grade serous ovarian cancer.

You had breast and high grade serous ovarian cancer.

You have relatives with breast, ovarian, pancreatic or prostate cancer.

Any men in your family had breast cancer.

You are of Ashkenazi Jewish ancestry.

A family member has a BRCA1 or BRCA2 genetic mutation.

“The most important thing is to identify first- and second-degree relatives who’ve had breast cancers in the family, and to know the ages at which they were diagnosed,” Arun says. If you’re unable to map your family’s cancer history – you may be adopted or not in touch with relatives – but had cancer at an early age, then you can undergo genetic testing. If you don’t have a personal history, but are still concerned, speak with your doctor.

 

Discuss your family history with your doctor

 

If your family history raises some red flags, take your complete family history form to your doctor to talk about your cancer risks. If your personal history has you worried, you also can seek your doctor’s advice.

 

“Your health care provider can help you decide if you should speak with a genetic counselor,” Arun says. “Genetic counseling is very comprehensive and important for understanding your inherited cancer risks.”

 

A genetic counselor will review your family’s medical history, discuss the role of genetics in cancer and perform a hereditary cancer risk assessment. Based on your cancer risk assessment, the genetic counselor may recommend genetic testing, which is a simple blood draw.

 

Understand the genes linked to breast cancer

 

If you learn that you have a family member with a gene linked to breast cancer, such as BRCA1 or BRCA2, don’t panic. Most breast cancer cases aren’t genetic. However, if you opt for genetic testing and find out you also have the gene, here’s what that means.

 

Most women that have a BRCA1 or BRCA2 genetic mutation, which is an abnormal gene, are diagnosed with Hereditary Breast and Ovarian Cancer (HBOC) syndrome. “This means you have up to an 87% chance of developing breast cancer,” Arun says.

 

It’s important for women with HBOC to begin cancer screening exams early. MD Anderson recommends:

 

Age 25 to 29: annual breast MRI.

Age 30 or older: annual mammograms and breast MRI, alternating the mammogram and breast MRI every six months.

Preventive surgery to remove the breasts, or prophylactic bilateral mastectomy, is another breast cancer risk management option. “It’s a very aggressive approach, but reduces your risk by up to 95%, which is why so many women are choosing it,” Arun says.

 

Assess genetic testing pros and cons

 

Finding out you have a genetic mutation means you can help prevent breast cancer or find it early, when your chances for successful treatment are highest. But your decision won’t just affect you. Your test results also could predict your family member’s cancer risks.

 

“Genetic counseling and testing is a very personal decision, and people need to want to know this information. Then they need to be ready to do something about it,” Arun says.

The Girl In The Glass
When you get what you want in your struggle for self
And the world makes you queen for a day
Just go to the mirror and look at yourself
And see what the girl has to say
For it isn't your father or mother
Who's judgment upon you must pass
The one who's verdict counts most in your life
Is the one staring back from the glass
You may be a Scarlett O'Hara
Or perhaps you're a little more shy
The girl in the glass really wont care
If you can't look her straight in the eye
She's the person to please never mind all the rest
For she's with you clear to the end
And you've passed the most dangerous test
If the girl in the glass is your friend
You may fool the world down the pathway of years
And get pats on the back as you pass
But your only reward will be heartache and tears
If you've cheated the girl in the glass.
~Not Mine~

 

 

 

 

 

 

 

 

Types of staging

Staging is done when a person is first diagnosed, before any treatment is given. The main types of staging are:

 

Clinical staging

This is an estimate of the extent of the cancer based on results of physical exams, imaging tests (x-rays, CT scans, etc.), and tumor biopsies. For some cancers, the results of other tests, such as blood tests, are also used in staging.

 

The clinical stage is a key part of deciding the best treatment to use. It’s also the baseline used for comparison when looking at how the cancer responds to treatment.

 

Pathologic staging

If surgery is being done, doctors can also determine the pathologic stage (also called the surgical stage) of the cancer. The pathologic stage relies on the results of the exams and tests mentioned before, as well as what is learned about the cancer during surgery. Often this is surgery to remove the cancer and nearby lymph nodes, but sometimes surgery may be done to just look at how much cancer is in the body and take out tissue samples.

 

Sometimes, the pathologic stage is different from the clinical stage (for instance, if the surgery shows the cancer has spread more than was thought). The pathologic stage gives the health care team more precise information that can be used to predict treatment response and outcomes (prognosis).

 

Staging systems

There are different types of staging systems, but the most common and useful staging system for most types of cancers is the TNM system.

 

The TNM system

The American Joint Committee on Cancer (AJCC) and the International Union for Cancer Control (UICC) maintain the TNM classification system as a tool for doctors to stage different types of cancer based on certain standards. It’s updated every 6 to 8 years to include advances in our understanding of cancer.

 

In the TNM system, each cancer is assigned a letter or number to describe the tumor, node, and metastases.

 

T stands for the original (primary) tumor.

N stands for nodes. It tells whether the cancer has spread to the nearby lymph nodes

M stands for metastasis. It tells whether the cancer has spread to distant parts of the body

The T category gives information about aspects of the original (primary) tumor, such as its size, how deeply it has grown into the organ it started in, and whether it has grown into nearby tissues.

 

TX means the tumor can’t be measured.

T0 means there is no evidence of a primary tumor (it cannot be found).

Tis means that the cancer cells are only growing in the most superficial layer of tissue, without growing into deeper tissues. This may also be called in situ cancer or pre-cancer.

Numbers after the T (such as T1, T2, T3, and T4) might describe the tumor size and/or amount of spread into nearby structures. The higher the T number, the larger the tumor and/or the more it has grown into nearby tissues.

The N category describes whether the cancer has spread into nearby lymph nodes.

 

NX means the nearby lymph nodes cannot be evaluated.

N0 means nearby lymph nodes do not contain cancer.

Numbers after the N (such as N1, N2, and N3) might describe the size, location, and/or the number of nearby lymph nodes affected by cancer. The higher the N number, the greater the cancer spread to nearby lymph nodes.

The M category tells whether the cancer has spread (metastasized) to distant parts of body).

 

M0 means that no distant cancer spread was found.

M1 means that the cancer has spread to distant organs or tissues (distant metastases were found).

Most cancer types have their own version of this classification system, so letters and numbers don’t always mean the same thing for every kind of cancer. For example, in some types of cancer, the T categories describe the size of the main tumor, while in others they describe how deeply the tumor has grown in to the organ it started in, or whether the tumor has grown into nearby structures (regardless of its size).

 

Some cancer types also have special groupings that are different from other cancer types. For instance, for some cancers, classifications may have subcategories, such as T3a and T3b, while others may not have an N3 category.