Amanda Peet's Breast Cancer Journey
- Actress Amanda Peet, a 54-year-old mom of three with dense breasts, was diagnosed with early-stage lobular breast cancer after a routine checkup, at a particularly difficult period in her left, when both of her parents were in hospice care. After follow-up imaging and a biopsy confirmed the diagnosis, she underwent a lumpectomy and radiation, sharing that her cancer was stage 1 with no need for chemotherapy.
- A lumpectomy removes the cancer or abnormal tissue from the breast, and unlike a mastectomy, only the tumor and some of the surrounding tissue are removed. For early-stage breast cancer, studies have shown that lumpectomy plus radiation is as effective a treatment in preventing a recurrence of breast cancer as mastectomy.
- Radiation helps kill cancer cells in a targeted way. With breast cancer, it is often used after surgery to kill off any cancer cells that may remain in the breast or surrounding area. Possible side effects may include swelling, fatigue, and scar tissue.
- Women with dense breasts are at a higher risk for developing breast cancer because dense breast tissue can mask potential cancer during screening. While mammograms are extremely valuable for breast cancer screening, more effective screening methods exist for women with dense breasts.
- 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.
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Actress Amanda Peet, who plays Mel Cooper in the Apple TV+ series “Your Friends & Neighbors,” is looking back on how a routine check-up led to an early stage diagnosis of lobular breast cancer.
In an deeply moving essay, published March 21 in The New Yorker, Peet revealed how she was diagnosed with breast cancer, during an incredibly challenging time, with both of her parents receiving hospice care.
Read MorePeet, 54, explained, “The Friday before Labor Day, I went for what I thought would be a routine scan. Dr. K. usually chatted me up while she examined me, but this time she went silent.
“She told me that she didn’t like the way something looked on the ultrasound and wanted to perform a biopsy. After the procedure, she said that she would walk the sample over to Cedars-Sinai and hand-deliver it to Pathology. That’s when I knew.”
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Recounting how she woke up to a text from her doctor with a “preliminary report” one day later, she was told the tumor in her breast “appeared to be small” but she needed n MRI to understand “the extent of disease.”
Peet also noted that her cancer was hormone-receptor-positive and HER2-negative, which remains the most common subtype of breast cancer.
- HR-positive breast cancer means the cancer cells have receptors for estrogen and/or progesterone, which can fuel their growth.
- HER2-negative indicates that the cancer cells do not over-express the HER2 protein.
RELATED: Medical oncologist Dr. Erica Mayer explains how CDK4/6 inhibitors treat hormone-receptor-positive breast cancers.
After an ultrasound and biopsy ultimately confirmed Peet’s cancer, a second tumor in the same breast was found to be benign, and her treatment consisted of a lumpectomy followed by radiation.
Peet kept her diagnosis from her mother, who was in hospice with late-stage Parkinson’s disease, and did not share news of her father’s death, which followed soon the actress’ diagnosis.
The mom of three, who shares her kids with her beloved husband, screenwriter David Benioff, then reflected on when her radiologist couldn’t find any evidence that her lymph nodes were involved, and identified a second lump in the same breast, saying, “We put my lumpectomy on hold, and she ordered an MRI-guided biopsy, which is when a tumor sample is extracted while you’re inside the big white imaging doughnut.”
Peet continued, “Two days later, we found out that the second mass was benign, and that I would only need a lumpectomy and radiation, not a double mastectomy or chemo. David and I decided to tell the girls.
“My therapist said that I didn’t have to appear strong or unfazed or have definitive answers. She said that I’d be surprised by how much children can step up and that calling for all hands on deck can make them feel useful.”
When she disclosed the news, she informed her children that the disease had appeared to be stage 1 and chemotherapy wouldn’t be needed.
Peet said she ultimately revealed her first clear scan at the start of this year, just two weeks before her mom’s hospice nurse advised her to call the mortuary.
Understanding Amanda Peet’s Breast Cancer Treatment
A lumpectomy removes the cancer or abnormal tissue from the breast, and unlike a mastectomy, only the tumor and some of the surrounding tissue are removed. The surgery typically takes about an hour and is an outpatient procedure, meaning a patient will be able to go home the same day. “It’s abnormal to have a lot of pain after a lumpectomy,” says Dr. Sarah Cate, Chief of Breast Surgery, Stamford Hospital.
WATCH: Recovering from a Lumpectomy
For early-stage breast cancer, studies have shown that lumpectomy plus radiation is as effective a treatment in preventing a recurrence of breast cancer as mastectomy.
“As the breast surgeon, I then make a cut in the breast and remove the cancer, and then I will do certain plastic surgery techniques to rearrange the tissue just in that area to make it look nice,” Dr. Cate explained.
“A lot of the time, the stitches are underneath the skin, and I use a skin glue. And that’s also taken from plastic surgery techniques for the best possible appearance of the scar. I also place the scars, most of the time, by the areola, or maybe at the bottom of the breast, so that patients can wear V-necks or bathing suits, and they really cannot see the scar after some time,” Dr. Cate continued.
Lumpectomy patients are usually at the outpatient surgery center for about four hours. If patients aren’t feeling well or experiencing additional pain or discomfort, they might stay longer.
Preparing for Radiation Treatment for Breast Cancer
Radiation therapy is often used after surgery to destroy any remaining cancer cells in the breast or surrounding tissue. As Radiation Oncologist Dr. Subhakar Mutyala told SurvivorNet, “Radiation therapy is actually ionizing energy, where energy goes through your body, essentially causes DNA damage… The actual treatment is just ionizing energy.”
Radiation therapy—using high-energy rays to destroy cancer cells—is a common follow-up to breast cancer surgery, especially for patients who choose a lumpectomy over a mastectomy. Its goal: reduce the risk of recurrence by targeting any lingering cancer cells in the breast or surrounding tissue.
While effective, radiation can come with side effects, both immediate and delayed. Common symptoms include:
- Fatigue
- Swelling
- Scar tissue
- Shortness of breath
One of the more serious concerns involves the heart, which can unintentionally absorb radiation due to its proximity to the breast.
“When the radiation is delivered, unfortunately, the heart happens to be somewhere very near to where they have their breast cancer, and it becomes an innocent bystander absorbing some of the radiation,” explained Dr. Jean-Bernard Durand to SurvivorNet, in an earlier interview.
This exposure can lead to complications such as fatigue, shortness of breath, and even heart failure—sometimes surfacing decades after treatment.
“We make it a point to see them on a regular basis so that we can catch these things very early and treat them,” Dr. Durand added.
Even advanced techniques like proton therapy, which aim to minimize damage to healthy tissue, aren’t immune to side effects. Fatigue remains a common complaint, and the risk of long-term injury still exists.
“Radiation is a form of energy… and when we give radiation, it has the ability to scatter,” Dr. Durand said. “Even though we may target one particular area, that scattering of energy can cause injury to the local surrounding structures, including the heart.”
Over time, this injury can lead to the development of scar tissue within the heart muscle, its electrical system, and blood supply.
“We believe it is what causes all the injury, that ultimately leads to the symptoms,” he explained.
For survivors, this underscores the importance of ongoing monitoring and open conversations with care teams.
WATCH: The Debates Around Radiation for Breast Cancer
While radiation is a standard part of care for many, experts continue to debate its scope and necessity. Dr. Chirag Shah of the Cleveland Clinic Cancer Center notes two key controversies: whether to use whole breast versus partial breast radiation, and whether some patients may not need radiation at all.
“The idea is reducing the duration of treatment and reducing side effects for patients,” Dr. Shah said. “Omitting radiation is therefore associated with a lower risk of side effects.”
Understanding Early-Stage Breast Cancer and What Comes Next
Early-stage breast cancer means the tumor is small and hasn’t spread to nearby lymph nodes. According to medical oncologist Dr. Elizabeth Comen, the first step is usually surgery to remove the cancer. This may involve a lumpectomy, where only the tumor and surrounding tissue are removed, often followed by radiation therapy to reduce the risk of recurrence.
However, treatment isn’t one-size-fits-all. Factors like age, tumor size, family history, and personal preference may influence whether radiation is needed or if a patient chooses a more aggressive approach, such as a mastectomy—removal of the entire breast. After surgery, a pathologist examines the tissue under a microscope to help determine the next steps in treatment.
WATCH: Understanding Early Stage Breast Cancer
Diagnostic testing plays a critical role in shaping your care plan. If a mammogram or clinical breast exam reveals something abnormal, your care team may recommend:
- Diagnostic mammogram and breast ultrasound to get a closer look at the breast and nearby lymph nodes
- MRI scans for additional imaging detail
- Biopsy of suspicious areas, including lymph nodes, to confirm cancer
- Tumor marker testing to identify hormone receptors and proteins that influence treatment options
- Additional imaging to check for any signs of metastatic disease
Once all this information is gathered, your cancer is staged—based on tumor size, lymph node involvement, and whether it has spread. Staging helps guide treatment decisions, while hormone receptor and protein marker tests reveal how the cancer behaves and which therapies may be most effective.
Your healthcare team will consider all of these factors—alongside your personal health, values, and goals—to create a treatment plan tailored to you.
Understanding Your Mammogram Report and Breast Density
A radiologist reading mammograms categorizes breasts into four different categories using the Breast Imaging Reporting and Data System (BI-RADS), a classification system developed by the American College of Radiology (ACR). These include:
- Fatty breast tissue: These breasts are mainly composed of fat with very little dense tissue. Found in less than 10% of women, fatty breasts appear dark on mammograms.
- Scattered fibroglandular breast tissue: These breasts contain a mix of fatty and dense tissue (composed of glands and fibrous tissue). On a mammogram, they have dark areas (fatty tissue) intermixed with light areas (dense tissue). Around 40% of women have breasts that fall in this category.
- Heterogeneously dense breast tissue: This type of breast tissue has many areas of dense tissue and some areas of fat. Found in 40% of women, these breasts look mostly light, with some dark areas on a mammogram.
- Extremely dense breast tissue: Such breasts are almost entirely composed of dense glandular and fibrous connective tissues with very little fat. They are found in 10% of women and appear light on mammograms.
Your breasts are usually called dense on a mammogram report if they fall within the heterogeneously dense breast tissue or the extremely dense breast tissue categories.
Additional screening methods are helpful for women with dense breasts because glandular tissue appears white on mammograms. Cancer and other abnormalities also exhibit a similar appearance. The “frosted glass” effect from the glandular tissue can thus mask cancerous areas, especially nascent ones. Undetected, these cancers can progress, growing large and advanced. They will then likely require more intensive treatments to cure or can become incurable altogether.
Helping Patients Better Understand Dense Breasts
- I Have Dense Breasts. Do I Need a 3D Mammogram?
- Millions of Women With Dense Breasts — A New Congressional Law — What You Need to Know
- When You’re Getting a Mammogram, Ask About Dense Breasts
- How to Avoid False Positive Cancer Results in Women With Dense Breasts: Ultrasounds Used in Addition To Mammograms
Enhanced Screening for Dense Breasts
Women with dense breasts may not know they have it based on feeling alone. Breast density is determined by its appearance on a mammogram. Dr. Connie Lehman, the chief of the Breast Imaging Division at Massachusetts General Hospital, explains to SurvivorNet that fatty breast tissue appears gray on an X-ray. Conversely, dense breast structures appear white during an X-ray. Cancers also appear white on an X-ray, meaning the dense breast structures can mask the possibility of cancer. Luckily, advanced mammograms exist to help doctors navigate this obstacle.
WATCH: 3D Mammograms explained.
“Digital mammography, it turns out, significantly improves the quality of the mammogram…It’s 3D or tomosynthesis mammography,” Dr. Lehman explains.
“This allows us to find more cancers and to significantly reduce our false-positive rate. With digital mammography 3D tomosynthesis, we’re taking thin slices through that breast tissue, like slices of a loaf of bread. We can look at each slice independently rather than trying to see through the entire thickness of the entire loaf of bread. So those thin slices help us find things that were hidden in all the multiple layers.”
Additional testing can be considered for dense breasts, depending on a woman’s personal history, preferences, and her physician’s guidance. These tests include:
- 3-D Mammogram (Breast Tomosynthesis): This technology acquires breast imaging from multiple angles and digitally combines them into a 3D representation of the breast tissue. This allows physicians to see breast tissue architecture better, even in dense breasts. 3D mammograms are fast becoming the standard way of performing mammography.
- Breast Magnetic Resonance Imaging (MRI): An MRI machine uses magnets to create highly detailed, intricate images of the breast. These are mostly reserved for women with an extremely high breast cancer risk. Dense breasts alone may not be a valid reason to obtain a breast MRI. However, dense breasts in women with genetic mutations, like BRCA1 and BRCA2, or a strong family history of breast cancer could justify obtaining breast MRIs.
- Molecular Breast Imaging (MBI): MBI is a newer imaging technique that uses a radioactive tracer to detect breast cancer. It is beneficial for women with dense breasts. However, MBI is not as widely available as other screening methods.
A new rule from the Food and Drug Administration (FDA) says that facilities offering mammograms must notify patients about their breast tissue density and recommend they speak with a doctor to determine if further screening is necessary. There will be “uniform guidance” on what language to use and what details to share with the patient to make the communication clear and understandable.
Breast Density Doesn’t Remain the Same Over Time, Impacting Your Cancer Risk
Women with dense breasts are at a higher risk for developing breast cancer. This connection has been demonstrated time and again in several rigorous scientific studies. 1 in 6 women with dense breasts are at risk for breast cancer. Comparatively, 1 in 8 women with average breasts are at risk for this cancer. The exact reason for this difference is not fully understood.
Researchers from Washington University School of Medicine in St. Louis and Brigham and Women’s Hospital in Boston analyzed this connection in a recent study.
They recruited 947 women between November 2008 and October 2020. All women were cancer-free at the start of the study and received yearly or bi-yearly screening mammograms. Researchers tracked the women’s mammogram reports and breast densities over time.
All women experienced a decline in their breast density during the 12 years. Two hundred eighty-nine women developed breast cancer during this time. Those who developed cancer had a lower rate of decrease in breast density than those who did not. The researchers concluded that the rate of breast density changes may indicate future breast cancer risk.
What To Ask Your Doctor
If you have been diagnosed with breast cancer, you may have questions about keeping your strength through treatment. Here are a few questions to help you begin the conversation with your doctor:
- What treatment will I be receiving?
- What side effects are associated with this treatment?
- Are there steps I can take daily to help minimize these side effects?
- What physical activity routine do you recommend for me during treatment?
- Do you have recommendations for someone who doesn’t particularly enjoy exercise?
- Can you recommend a dietician who can help me with healthy eating tips and weight maintenance?
- I’ve been having trouble sleeping. Do you have any treatment recommendations?
Contributing: SurvivorNet Staff
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