With Covid-19 cases rising again, some people worry that breast cancer treatments such as tamoxifen or trastuzumab (Herceptin) might lower their immune system, putting them more at risk. But not all cancer treatments affect the immune system. Last updated 15 December 2021.
1. Breast cancer treatment and your immune system
2. Does hormone therapy affect the immune system?
3. Does trastuzumab (Herceptin) lower your immune system?
4. Does having lymph nodes removed affect your immune system?
5. Who is more at risk from Covid-19?
6. What you can do to stay as safe as possible
7. Coping with worry
Some cancer treatments, such as chemotherapy, affect the immune system making it harder for the body to fight infections. This can increase the risk of becoming seriously ill if you get Covid-19, although being fully vaccinated reduces the risk.
However, not all cancer treatments affect the immune system.
Read more about breast cancer treatment and Covid-19 risk.
Taking hormone therapy, including tamoxifen, letrozole, anastrozole, exemestane and goserelin, does not affect your immune system.
Hormone therapies do not increase your risk of getting coronavirus or of becoming seriously ill if you do get it.
Covid-19 vaccines are also safe and effective for people having hormone therapy.
Having trastuzumab (Herceptin) could mean you’re more at risk of getting coronavirus or becoming very ill if you get it.
The risk is likely to be higher if you’re having it with chemotherapy.
However, being fully vaccinated against Covid-19 reduces the risk.
Having lymph nodes removed does not affect your body’s ability to fight infections.
It’s common to have lymph nodes under the arm removed as part of surgery for breast cancer.
While having lymph node surgery increases the risk of a condition called lymphoedema, having nodes removed or having lymphoedema does not affect the overall ability of the immune system to fight infection.
Having certain treatments for breast cancer could mean you’re more at risk of getting an infection such as Covid-19, and more at risk of becoming seriously ill if you do get it.
However, most people having cancer treatment will have been fully vaccinated, reducing the risk of serious illness.
People considered more at risk include those having:
- Immunotherapy or targeted (biological) therapies such as trastuzumab emtansine (Kadcyla) or everolimus (Afinitor)
- Trastuzumab (Herceptin), or trastuzumab with pertuzumab (Perjeta), with or without chemotherapy (the risk is likely to be smaller if you’re not having chemotherapy as well)
- Other targeted (biological) therapies which can affect the immune system, including palbociclib (Ibrance), ribociclib (Kisqali) and abemaciclib (Verzenios)
Compared with chemotherapy drugs, targeted therapies tend to have fewer serious side effects. However, they can still cause problems in some people.
Because of this, it’s best to contact your hospital team to check your individual risk.
People on these treatments usually have regular blood tests to check their white blood cell count. A low white blood count means you’re more at risk of infection.
If you’re having any of these treatments, you may be advised to take extra precautions to protect yourself.
If you’re worried about your risk from Covid-19, there are things you can do to help protect yourself. These include:
- Having both doses of a Covid-19 vaccine (and a third vaccine if you are offered one by your treatment team or GP)
- Having a booster vaccine
- Considering limiting close contact with people you do not usually meet
- Meeting people outside where possible
- Asking people you are meeting to take a rapid lateral flow test beforehand
- Wearing a face covering in crowded areas, such as on public transport
The government has information for people who were previously considered clinically extremely vulnerable from Covid-19.
While the pandemic has been hard for everyone, it may have been particularly difficult if you were dealing with a cancer diagnosis or going through treatment.
You may find it helpful to talk to someone about how you’re feeling. You can call our Helpline free on 0808 800 6000.
You may also find it useful to read our tips on managing stress and anxiety.
Need to talk to someone? Our breast care nurses and highly trained staff on our free and confidential Helpline are here for you.