Answers to common questions about navigating COVID-19 and breast cancer, COVID vaccines and mammograms, and more

As the pandemic rages on, people with breast cancer, survivors, and loved ones are still dealing with layers of fear and uncertainty about staying safe, especially while undergoing treatment.

The best advice for navigating breast cancer now is to talk to your doctor about your individual situation and concerns. Below you will find expert guidance on some common questions and concerns, including whether patients need COVID-19 vaccine booster shots.

This page is continuously updated as recommendations evolve and new developments break.

How can I protect myself from COVID-19?

The approved vaccines help prevent severe illness and death from COVID-19, and they reduce both your risk of getting the disease or spreading it.

To help protect yourself from COVID-19—and especially from current and emerging variants—play it safe and wear a mask when you’re in indoor public spaces if you are in an area of “substantial or high transmission” (use the CDC’s map here). Review the CDC’s guidelines for mask fit, filtration, and layering to ensure you are maximizing your mask’s protection. Wash your hands frequently and try to maintain distance from others in public spaces.

If you are immunocompromised because of cancer treatment or any other reason, the CDC advises you wear a mask at all times outside your home—even if you are vaccinated.

How do the COVID-19 vaccines work?

The vaccines for COVID-19, like those for influenza and other infectious diseases, all work by introducing your body to a foreign pathogen (or part/piece of one) to kick your immune system into action. As your immune system fights back, it develops T and B cells to “remember” how to do so again in the future. This means that you can develop immunity against COVID-19 without being exposed to it. The two-dose Pfizer/BioNTech vaccine and the Moderna vaccine do this with mRNA technology, while the one-dose Johnson & Johnson’s Janssen shot is a vector vaccine. None of the vaccines will give you COVID-19. You can read more here.

How effective are the COVID-19 vaccines?

Real-world studies have so far shown that the two approved mRNA COVID-19 vaccines (Moderna and Pfizer-BioNTech) are effective and reduce the risk of COVID-19 infection and severe illness. A major real-world study by the CDC published in September 2021 found that among adults who are not immunocompromised, the Moderna vaccine was 93 percent effective at reducing the risk of COVID-19 hospitalization and Pfizer-BioNTech was 88 percent effective. Real-world studies have confirmed that the recommended two doses of the mRNA vaccines are superior to one. The results have been similar to those reported during controlled clinical trials.

In the same real-word study above, Johnson & Johnson’s Janssen vaccine was found to be 71 percent effective at preventing hospitalization. However, boosters have been shown to significantly increase their effectiveness (read more on boosters below).

Who should get the COVID-19 vaccine?

The CDC now recommends that everyone five years and older be vaccinated against COVID-19.

Can you still get COVID-19 even if you are vaccinated​?

No vaccine is 100 percent effective, so it is possible to contract COVID-19 while vaccinated. These are called vaccine breakthrough cases. The good news is that in the event that you’re infected after vaccination, research has shown that you’re still protected against severe illness and death.

Are vaccines as effective for breast cancer patients​?

Cancer treatments such as chemotherapy and radiation suppress the body’s immune system. Because of that, the CDC has warned that the vaccines may not offer full protection to immunocompromised people, making them particularly vulnerable to breakthrough infections. Still, some protection is better than nothing.

Talk to your healthcare team about your options. And because cancer patients may be at an increased risk of breakthrough infections, your caregivers, family, and friends should consider vaccination to protect you.

Who should get a COVID-19 booster vaccine?

The CDC recommends booster shots for all people 12 and up. The agency has also recommended select groups get a second booster: moderately to severely immunocompromised people (including those in active treatment for cancer), everyone age 50 and over, and those who got two doses (a primary and a booster) of Johnson & Johnson’s Janssen vaccine.

The FDA has authorized booster “mixing and matching” following research showing that mRNA vaccines seem to produce stronger immune responses. If you received Johnson & Johnson’s Janssen vaccine in particular, ask your doctor if you should consider a booster of Moderna or Pfizer-BioNTech.

Why do people need vaccine booster shots if the vaccines are effective?

While the approved vaccines are incredibly effective at preventing severe illness, hospitalization, and death—even against highly transmissible variants—research has shown that the vaccines may lose some protection over time. This is not a sign that the vaccines don’t work.

Research is ongoing on booster shots, but studies so far have shown they can enhance protection. The phase 3 ENSEMBLE 2 clinical trial, for example, found that a booster of Johnson & Johnson’s Janssen vaccine provided significant increases in protection—to similar levels as the two approved mRNA vaccines. A study of 1.1 million people over 60 in Israel found that 12 days after a booster dose, rates of COVID-19 infection and severe illness were substantially lower.

Should breast cancer patients receive booster shots of the vaccine​?

The CDC recommends that immunocompromised people get another dose to boost their immune responses. This guidance applies to all three approved vaccines.

How long does it take the vaccines to reach full effectiveness?

According to the CDC, it generally takes two weeks for vaccines to provide maximum immunity. This means that you are not considered fully vaccinated against severe COVID-19 until two weeks after the second dose of the Pfizer-BioNTech or Moderna vaccines or two weeks after the one-dose Johnson & Johnson/Janssen vaccine.

Is the COVID-19 vaccine safe for breast cancer patients?

Early information indicates that the leading vaccines are safe for cancer patients. The leading COVID-19 vaccines do not use live viruses that can cause serious side effects for patients undergoing immunosuppressive treatments. The CDC has outlined how each of the major types of vaccines (mRNA, vector, and protein subunit) work here.

Can I resume my normal activities and stop wearing a mask after vaccination?

The CDC recommends that everyone, including fully vaccinated Americans, wear a mask in indoor public spaces again in areas of the country where COVID-19 transmission is "high" or "substantial." You can check transmission in your area here. Unvaccinated and immunocompromised people should continue to wear masks in public in all areas.

RELATED: COVID-19 and Breast Cancer: BCRF's Resources for Patients During the Coronavirus Crisis

Do the vaccines work against COVID-19 variants?

Researchers are continuing to investigate how effective the current vaccines perform against variants. But data has so far shown that full vaccination is effective at preventing severe disease and death. An analysis of data from Britain released December 31 found that compared to people who were unvaccinated, those who got two doses of a vaccine had a 65 percent lower risk of being admitted to a hospital after contracting the Omicron variant and those who got a booster had an 81 percent lower risk.

Should I delay my mammogram because a COVID-19 vaccine side effect could cause swollen lymph nodes under my armpit?

The swelling of the lymph nodes under your arm—known as axillary adenopathy—is a rare occurrence but can raise red flags on a mammogram as a sign of breast cancer itself or that breast cancer has spread. While this condition has very rarely been reported following injections of influenza and other vaccines, higher rates of axillary adenopathy have been reported in the two COVID-19 vaccines currently available from Moderna and Pfizer in early, self-reported data. As a result, the Society of Breast Imaging recommends that women schedule their annual screening prior to the first dose of a COVID-19 vaccine or four to six weeks after the second dose. In addition, the organization is also recommending that providers ask patients about COVID-19 vaccine status.

However, these guidelines do not suggest women skip screenings because of their COVID-19 vaccine status. Your annual screening is still a critical tool for early diagnosis. If you have received or are in the process of receiving the COVID-19 vaccine and are due for your annual mammogram soon, talk to your doctor before delaying your mammogram.

Are there any other major COVID-19 vaccine side effects that people with cancer need to be aware of?

So far, serious reactions to any of the three available vaccines have been rare. The most common side effects are pain and swelling in your vaccinated arm, along with fever, chills, fatigue, and headache. These are normal bodily responses and a sign that the vaccine is working (though it should be noted, if you don’t experience any symptoms, the vaccine is still working). Read more about what to expect after you get your vaccine here.

After temporarily pausing the use of the Johnson & Johnson Janssen vaccine, the federal government recommended that the vaccine resume with a new warning about an extremely rare risk of blood clots in women under 50 years old. If you received the Johnson & Johnson Janssen vaccine, the CDC has a list of symptoms to look out for and resources here.

How else will the COVID-19 vaccine help cancer patients?

In addition to saving lives by stopping the spread of the virus and easing the considerable burden of the pandemic on the national healthcare system, the vaccines also protect cancer patients and others who are most vulnerable to infection (through herd immunity). The COVID-19 vaccines will not only help prevent infection overall, but also prevent severe illness. Experts also hope that vaccines will encourage Americans to get their annual cancer screenings—one of the best tools doctors have to detect the disease early.

Do cancer patients have a higher risk of contracting COVID-19? Am I immunocompromised because of my treatments? 

Cancer patients in active treatment can be immunocompromised, contributing to a higher risk of severe illness. People being treated for breast cancer may also be at a higher risk of severe illness from COVID-19 because of other, unrelated medical conditions or immunosuppressive treatments.

For breast cancer patients, chemotherapy tends not to be as toxic to the immune system (compared to chemotherapy for other kinds of cancers, like leukemia, which is generally more intense and wipes out the entire immune system). But chemotherapy can affect a patient’s ability to fight bacteria, and for that reason, they’re given injections to boost white blood cell counts.

Cancer patients whose treatment protocols involve immunotherapy have a special set of concerns. In general, immunotherapy isn’t a widespread treatment for breast cancer, but it is sometimes used for subtypes like triple-negative breast cancer. Immunotherapy can affect the lungs, potentially making patients more vulnerable to COVID-19.

Patients getting hormonal therapy may not feel completely normal during their treatments, but their immune systems are much less compromised.

The bottom line: All patients undergoing treatment should follow the CDC’s advice to protect themselves and get vaccinated. Those undergoing chemotherapy and immunotherapy should be extra cautious and consult with their doctors about additional precautions.

Are cancer survivors at higher risk for COVID-19? Are cancer survivors immunocompromised?

According to the National Cancer Institute, at this time, research has not definitively shown that a history of breast and other cancers alone increases a person’s risk of a more severe illness from COVID-19. Breast cancer survivors are not generally immunocompromised by past treatments, but they should talk to their doctors about any concerns or underlying conditions. Breast cancer survivors, however, may be at a higher risk of COVID-19 because of other, unrelated underlying medical conditions or because they are receiving immunosuppressive treatments (such as corticosteroids). It is important to discuss your immunocompromised status with your doctor.

Should I continue to go to chemotherapy and radiation treatments?

It’s fair to be concerned about getting treatment during the pandemic. Hospitals and treatment centers are aware of this and have put extra precautions in place to protect patients and staff. Things have changed since the start of the pandemic. By and large, it is safe to go to the doctor or a hospital as long as you wear a mask and practice social distancing from other patients.

Your treatment is important. Most of the time, doctors will try to keep treatments on schedule. But again, consult with your doctor about whether he or she advises any modifications.

What about mammograms and other routine screenings?

Early in the pandemic, hospitals and screening facilities closed due to COVID-19, and many women had their routine mammograms postponed or canceled. Patients showing symptoms of breast cancer did not experience large-scale disruptions.

Since those initial closures, screening facilities have changed their waiting room layouts, check-in processes, cleaning procedures, and more to make mammograms safe. Still worried? Make an early morning appointment to cut down on time in the waiting room. And if your mammogram was canceled or you missed one for any other reason, call to reschedule as soon as possible.

RELATED: Breast Cancer Screening and COVID-19: What Patients Need to Know Now

What COVID-19 symptoms should breast cancer patients be on the lookout for?

The most important coronavirus symptoms to pay attention to are fever and shortness of breath. Breast cancer patients in treatment should always be on the lookout for those symptoms anyway. Call your doctor at the first sign.

Other symptoms to be aware of, according to the CDC: chills, cough, a new loss of taste or smell, fatigue, muscle or body aches, headaches, sore throat, congestion, nausea or vomiting, and diarrhea.

How will COVID-19 impact breast cancer diagnoses and care?

The full effects of COVID-19 on breast cancer diagnoses and outcomes may not be realized until long after the pandemic, but we do know COVID-19 has complicated crucial aspects of cancer care and research is predicting it will lead to more breast cancer deaths.

What guidance do you have for managing stress?

We’re all living with more stress than usual. There are several helpful online tools for everything from yoga to therapy. Finding a way to feed your inner self is critical for patients and their caretakers, too. Schedule yoga, exercise, or any activity you know makes you calm. Eat healthfully, reduce alcohol, focus on a good night’s sleep.

Meditation has been shown to reduce stress and strengthen your immune system. Find several free mindfulness exercises and advice for starting a new practice from a BCRF researcher here.

This article was originally published on March 26, 2020 and has been updated since.



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