Some of the most important questions you'll have after getting a cancer diagnosis will be about treatment. You'll want to know which treatments are options for you, how long they may last, and possible side effects.
Many cancer treatments can cause other health problems, and they're often specific to the type of treatment you get. Treatments for estrogen receptor-positive (ER-positive), human epidermal growth factor 2-negative (HER2-negative) metastatic breast cancer with an ESR1 mutation can cause both mild and serious side effects.
What Is ER-Positive Metastatic Breast Cancer With ESR1 Mutation?
Around three-quarters of breast cancers are at least partially fueled by the hormone estrogen. Doctors call these cancers estrogen receptor-positive because their cells have receptor proteins that "turn on" when attached to estrogen.
Although your ER-positive breast cancer may improve with hormone therapy at first, your tumor can grow and spread later (called metastatic cancer).
Why does breast cancer spread?
To understand why your breast cancer can spread, researchers have collected and tested samples of drug-resistant, metastatic tumors. The studies have homed in on specific gene mutations that can cause your tumor to grow. And the ESR1 mutation is one of these gene changes.
The ESR1 gene mutation
The ESR1 gene helps build the estrogen receptor, but gene changes can change its shape. This new receptor shape acts like it's attached to estrogen hormone, even though it isn't.
Experts found that without hormone therapy, most breast cancer tumors don't get the ESR1 gene mutation. This suggests that hormone therapy may lead to treatment resistance.
Treatment resistance means your cancer stops responding to the medication, often because of a gene change. With the ESR1 mutation, the receptor changes shape and turns on cancer cell growth, even without estrogen.
That's why it's important to target the estrogen receptor with specific medications that can stop the growth of your breast cancer cells.
Treatments and Side Effects
Treatment for ER-positive, HER2-negative metastatic breast cancer with an ESR1 gene mutation include selective estrogen receptor degraders (SERDs) and a newly approved targeted therapy -- proteolysis targeting chimera (PROTAC), a targeted protein degrader. But like most cancer medicines, these medicines can cause side effects.
Imlunestrant (Inluriyo)
Imlunestrant blocks estrogen from attaching to your cancer cells. The medicine attaches to estrogen receptors on your tumor to change their shape and make them less able to function.
Serious side effects
You could also have more serious side effects while taking imlunestrant.
Fulvestrant (Faslodex)
Like imlunestrant, fulvestrant also blocks the effects of estrogen on hormone receptor-positive breast cancer cells, stopping them from growing and multiplying.
Serious side effects
Fulvestrant can also cause more serious side effects.
Tell your doctor right away and get medical help if a cut doesn't stop bleeding.
Elacestrant (Orserdu)
Elacestrant also binds to estrogen receptors to change its shape and make the receptor less effective.
Serious side effects
Less often, elacestrant can lead to serious side effects.
Camizestrant (Etcamah)
Camizestrant (Etcamah) blocks and breaks down estrogen receptors to help stop the cancer cells from growing. It's used along with the CDK4/6 inhibitor.
Serious side effects
Camizestrant may cause some serious side effects.
Vepdegestrant (Veppanu)
Vepdegestrant (Veppanu) is the first FDA-approved PROTAC, a targeted protein degrader. It is an oral cancer drug taken once daily with food for people ER-positive (ER+) HER2-negative , ESR1-mutated advanced or metastatic breast cancer, whose disease has progressed after at least one prior hormone (endocrine) therapy. An FDA-authorized test confirming ESR1 mutation must be given before starting treatment.
Serious side effects
Vepdegestrant may have some less common but more serious side effects.
Managing Treatment Side Effects
Some side effects of hormone therapies like SERDs are short-term, but many last longer. To ease cancer treatment side effects, your doctor can prescribe medication or suggest other treatments.
Lifestyle Changes
The foods you eat, activity, and other lifestyle changes can help lessen your cancer treatment side effects. Here are a few tips to help you get started.
Diet
Eating a healthy and balanced diet during cancer treatment can help you feel better and stay strong. This means getting enough nutrients such as vitamins, minerals, protein, carbohydrates, and fats.
To do this, you can try to eat:
- Plenty of fruits and vegetables
- Whole-grain bread and cereals
- Moderate amounts of lean meat like chicken and fish
- Low-fat or fat-free dairy
- Small amounts of fats, sugars, alcohol, and salt
You may need more calories and protein than usual. That's because cancer and cancer treatment can affect how your body uses nutrients and your appetite.
Ask your health care team about seeing a registered dietitian or nutritionist. They can help you manage your nutritional needs and even give you recipe ideas.
Stay hydrated
Drink small amounts of liquids all day. This can help keep you hydrated throughout the day and help you balance nausea, too. There are lots of ways to get more fluids into your body. You can:
- Eat foods that contain more water, like melons, veggies, soups, or other moist foods.
- Drink cold fluids on ice to help it go down easier.
- Suck on a popsicle or shaved ice to get your fluids.
- Stay away from caffeinated and alcoholic beverages.
Natural supplements
Some natural supplements can help reduce the side effects of hormone therapy. These include vitamin D, calcium, magnesium, and probiotics. Before adding any new vitamins or supplements to your treatment plan, talk to your doctor about possible drug interactions.
Activity
SERDs and other hormone therapies for cancer often cause weight gain, muscle and joint pain, and osteoporosis. Daily activity – around 20 minutes a day – can help ease these side effects.
Sleep
To reduce fatigue, stick to a regular sleep schedule, take breaks during the day, and start exercising.
Stop smoking and drinking
Alcohol and smoking can harm your health, especially if you have breast cancer. Quitting can help lessen treatment side effects.
Even if you can cut back on smoking and drinking, it can improve your overall well-being. And, it lowers the chance of breast cancer coming back.
Manage hot flashes
You can manage hot flashes by wearing loose clothing, lowering your stress, and avoiding spicy foods, caffeine, and alcohol. If needed, your doctor may prescribe medication to help ease hot flashes.
Vaginal lubricants
If you have vaginal dryness or feel pain during sex because of it, try using water-based lubricants before intercourse. If the dryness or discomfort continues, talk to your gynecologist. In some cases, they may prescribe a low dose of estrogen in a vaginal tablet form.
Managing mental health
Managing the side effects of cancer treatment also involves taking care of your mental health. Here are some steps you can take:
Find Support
Talking to Your Doctor
Your cancer doctor should be the first person you talk to if you have treatment side effects. They'll offer suggestions for managing them and help you feel better. When speaking to your care team about the side effects of breast cancer treatment, being organized can help.
Keep a journal to note your side effects, how long they last, and how much they affect your daily life. The more information, the better. It will make it easier for your doctor to support you.
Be honest about your symptoms. Your cancer care team needs to know about your side effects to help you treat them. If it makes you feel more comfortable, ask to talk to a female doctor or nurse.
Show Sources
Photo Credit: iStock/Getty Images
SOURCES:
Breastcancer.org: "FDA Approves Imlunestrant (Inluriyo) for Certain HR-Positive Breast Cancers," "Faslodex (fulvestrant) for Breast Cancer: What to Expect, Side Effects, and More," "Orserdu (elacestrant): What to Expect, Side Effects, and More."
Memorial Sloan Kettering Cancer Center: "MSK Discovery of ESR1 Gene Mutation Leads to Approval of Breast Cancer Drug Elacestrant."
Compass Oncology: "A Guide for Current Breast Cancer Patients," "Common Side Effects of Breast Cancer Treatments."
The American Journal of Managed Care: "Monitoring and Managing Adverse Effects With Oral SERDs."
National Breast Cancer Foundation Inc: "Side Effects of Breast Cancer Treatment and How to Manage Them."
CDC: "Staying Healthy During Cancer Treatment."
Boston Medical: "Taking Care of Your Mental Health When You Have Cancer."
FDA: “FDA approves vepdegestrant for ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer.”
