Movie Star Jessica Chastain, 47, Takes Her Grandmother To Doctor’s Appointment For Breast Cancer Treatment; “For Grandma Get Your Mammograms Immediately!”

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A post shared by Jessica Chastain (@jessicachastain)

Chastain captioned the awareness-raising post, “My beautiful grandma Marilyn, who many of you have met at different events, was recently diagnosed with breast cancer.

“This week, I flew to meet with her amazing doctors and surgeons who are providing her the best possible care. I’m beyond grateful to the incredible hospital staff. She’s a total badass, and I know she’ll get through this.”

The California-native and loving mom of two continued, “In honor of Breast Cancer Awareness Month, she asked me to remind all of you: schedule your mammogram today.

“You are so important to so many people—please make this a priority.”

Chastain’s grandma Marilyn Herst also offered some words of wisdom when it comes to finding breast cancer early, telling those watching her famous granddaughter’s Instagram video, “I feel so grateful for the fact that I found it so early because it’s so treatable.

“But if you don’t take care of yourself and check yourself or even have your regular mammograms, you may not catch it early and it may not help you.”

RELATED: When Should I Get a Mammogram?

She further urged, “So I really want you to go out and do that. Please, for me,” as her sweet granddaughter chimed in, “For grandma! Go get your mammograms immediately please.”

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A post shared by Marilyn Herst (@motorcyclegramma)

Herst first introduced herself as “motorcycle grandma” in the sweet video clip before explaining she wanted to “encourage” others to “observe Breast Cancer Month.”

As for what led to her diagnosis, she explained, “I felt a small tiny thing in my breast. I did mention in in my annual physical, and had my mammogram, and I am being treated now for positive breast cancer.”

Although she didn’t go into detail on her exact treatment plan, we’re happy to see her going public with her news and trying to make a difference by helping others discover their breast cancer earlier than later.

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A post shared by Marilyn Herst (@motorcyclegramma)

What to Know About Screening For Breast Cancer

The medical community has a consensus that women between 45 and 54 have annual mammograms. However, an independent panel of experts called the U.S. Preventive Services Task Force (USPSTF) is saying that women should start getting mammograms every other year at the age of 40, suggesting that this lowered the age for breast cancer screening could save 19% more lives.

WATCH: Screening for Breast Cancer

For women aged 55 and older, the American Cancer Society recommends getting a mammogram every other year. However, women in this age group who want added reassurance can still get annual mammograms.

Women who have a strong family history of breast cancer, have dense breasts, have a genetic mutation known to increase the risk of breast cancer, such as a BRCA gene mutation, or a medical history, including chest radiation therapy before age 30, are considered at higher risk for breast cancer.

Understanding the BRCA Gene Mutation

Experiencing menstruation at an early age (before 12) or having dense breasts can also put you into a high-risk category. If you are at a higher risk for developing breast cancer, you should begin screening earlier.

Breast density is determined through mammograms. However, women with dense breasts are at a higher risk for developing breast cancer because dense breast tissue can mask potential cancer during screening. 3D mammograms, breast ultrasound, breast MRI, and molecular breast imaging are options for women with dense breasts for a more precise screening. It is important to ask your doctor about your breast density and cancer risk.

Although breast cancer can happen to anyone, certain factors can increase a person’s risk of getting the disease. The known risk factors for breast cancer include:

• Older age
• Having a gene mutation such as the BRCA1 or BRCA2
• Added exposure to estrogen
• Having children after the age of 30
• Exposure to radiation early in life
• Family history of the disease

RELATED: Is Genetic Testing Right for You?

Different types of genetic testing can help people with a family history of cancer better ascertain their cancer risks. Your doctor will discuss your family history of cancer with you in the context of your type of tumor and your age at diagnosis. Hereditary genetic testing is usually done with a blood or saliva test.

The second test involves the genetic sequencing of your tumor if you’ve been diagnosed with cancer by this point. These genetic changes can be inherited, but most arise during a person’s lifetime. This process usually involves examining a biopsy or surgical specimen of your tumor. This testing can lead to decisions on drugs that might work against your cancer.

WATCH: Understanding genetic testing for breast cancer.

About ten percent of breast cancers are hereditary, says Dr. Ophira Ginsburg, Director of the High-Risk Cancer Program at NYU Langone’s Perlmutter Cancer Center.

“We encourage only those who have a family history to really get [genetic testing],” Dr. Ginsburg previously told SurvivorNet.

“I would say that if you have anyone in your family who was diagnosed with a very rare cancer. Or if you have a strong family history of one or two kinds of cancer, particularly breast and ovarian, but also colon, rectal, uterine, and ovarian cancer, that goes together in another cancer syndrome called the Lynch Syndrome,” Dr. Ginsburg adds.

When You’re Getting a Mammogram, Ask About Dense Breasts

Treating Breast Cancer

For anyone battling breast cancer, it’s important to understand that your doctor has many ways to treat breast cancer, including:

• Surgery
• Chemotherapy
• Radiation
• Hormone therapy
• Targeted therapy
• Immunotherapy

“It’s important to understand why your doctor is recommending a particular type of treatment,” Johns Hopkins Kimmel Cancer Center’s Dr. Jessica Tao previously told SurvivorNet.

Breast Cancer: Introduction to Prevention & Screening

Surgery

Most women with breast cancer will have surgery at some point in their treatment. Depending on how far your cancer has spread and your personal preferences, you and your doctor may decide to:

• Remove just the cancer and an area of healthy tissue around it (lumpectomy)
• Remove one breast (mastectomy)
• Remove both breasts (double mastectomy)
• Removing your breasts can have a dramatic effect on your self-esteem, which is why some women who opt for a mastectomy then choose breast
• reconstruction surgery. This is a highly personal choice, and there is no “right” answer as to whether or not to reconstruct.

Chemotherapy

Chemotherapy uses strong drugs to kill cancer all over the body. You may get this treatment to shrink a tumor before surgery, afterward to get rid of any remaining cancer cells, or on its own if you can’t have surgery.

Whether or not to have chemotherapy can also be a choice, depending on a woman’s age, type of cancer, and stage.

Radiation Therapy

Radiation therapy is the use of high-energy rays to destroy cancer cells and is typically used after surgery to lower the chance that the cancer will come back after treatment. Many women undergo radiation as part of their treatment, especially if they opt for a lumpectomy instead of a mastectomy.

Hormone Therapy

The hormones estrogen and progesterone help some breast cancers grow. Doctors refer to these types of cancers as hormone-receptor-positive breast cancers. Receptors are proteins on the surface of breast cells that receive messages from estrogen, progesterone, or both, telling them to grow. Treatments that block these hormones may help stop the tumor.

Testing the tumor sample from a biopsy helps to determine whether hormone therapies such as tamoxifen (Nolvadex) or anastrozole (Arimidex) might work against the cancer. Women with breast cancer that is fueled by estrogen may take one of these drugs as part of their treatment.

Immunotherapy and Targeted Therapy

Immunotherapy and targeted therapies are newer forms of treatment. Immunotherapy boosts your body’s own immune response to help it stop the cancer.

As their name suggests, targeted therapies target certain substances that help the cancer grow. For example, drugs like trastuzumab (Herceptin) and pertuzumab (Perjeta) treat breast cancers that have too much of a protein called HER2 on their surface.

Deciding the Right Course of Breast Cancer Treatment

Doctors treating breast cancer seek out markers on your particular cancer to help decide what course of treatment is best for you. This is due to the cancer cells possibly having what are known as receptors that help identify the unique features of the cancer.

The three main receptors are the estrogen receptor, the progesterone receptor, and the HER2 receptor. The estrogen and progesterone receptors go together because they are fueled by hormones. Think of the cancer cell as having little hands on the outside of the cell which grabs hold of proteins that help it grow. These proteins are sometimes called “ligands.”

An example of a type of ligand that can stimulate a cancer cell is the hormone estrogen. An estrogen receptor-positive breast cancer will be stimulated by estrogen to grow. In this instance, your doctor may offer you treatment to specifically target the estrogen receptor.

The Unique Features of Breast Cancer

Another important receptor to test for is the HER2 receptor. For HER2 positive breast cancers (like the stage zero cancer Macpherson was diagnosed with), therapies that uniquely target the HER2 receptor are essential to treating the disease.

Contributing: SurvivorNet Staff

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