COVID-19 Vaccine FAQs

Cancer patients are at increased risk of severe COVID-19 and should get vaccinated, unless their physician advises otherwise or they have a history of severe allergic reaction to a vaccine or a medication in the past requiring you to seek immediate medical care. Cancer patients should discuss vaccination with their provider to understand the effectiveness of vaccines for those being treated for cancer.

The Centers for Disease Control and Prevention (CDC) urges immunocompromised people ages 5 years and older to receive a COVID-19 vaccine primary series as soon as possible.

However, if you recently received cancer treatment —such as chemotherapy, bone marrow transplant, stem cell treatment or cell therapy—your doctor may suggest that you wait to be vaccinated until your immune system has recovered. 

Recent COVID-19 vaccine trials did not include a large number of cancer patients. However, these vaccines do not contain live virus and non-live vaccines are generally considered safe - and are commonly recommended - for cancer patients.

Vaccine effectiveness may be reduced in cancer patients with suppressed immune systems as the ability to mount a response to the vaccine may be limited. Still, the benefit of vaccination is considered greater than the risk of not getting the vaccine, barring any contraindications.

After receiving the vaccine, it is advisable for cancer patients, like everyone, to continue masking, cleaning hands and physical distancing.

We do not recommend that patients delay cancer treatments to get vaccinated. However, a physician and patient may decide to hold off on treatment on a case-by-case basis depending on the urgency of treatment, the seriousness of illness, and the risk and benefit of delay.

Patients getting mammograms or CT scans may show enlarged lymph nodes after vaccination, a common physical response to the vaccine. These results may lead to further testing to rule out cancer as the cause. For this reason, if there is no urgent reason for immediate imaging, it is best to get these screening tests either prior to your COVID-19 vaccination or 4 to 6 weeks after vaccination.

Additional dose

Moderately to severely immunocompromised people who have received an mRNA COVD-19 vaccine primary series (Pfizer BioNTech or Moderna) should receive an additional (third) dose. An additional primary dose may prevent serious and possibly life-threatening COVID-19 in people who may not have responded to their two-dose mRNA COVID-19 vaccine primary series. 

Currently, moderately to severely immunocompromised people ages 18 years and older who completed their Moderna vaccine primary series should plan to get an additional primary dose 28 days after receiving their second shot. For people ages 12 years and older who completed their Pfizer-BioNTech vaccine primary series, they should also plan to get an additional primary dose 28 days after receiving their second shot. This includes people who have:

• Been receiving active cancer treatment for tumors or cancers of the blood
• Received an organ transplant and are taking medicine to suppress the immune system
• Received a stem cell transplant within the last 2 years or are taking medicine to suppress the immune system
• Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
• Advanced or untreated HIV infection
• Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response

People should talk to their healthcare provider about their medical condition, and whether getting an additional primary dose is appropriate for them.

Booster

Everyone ages 18 years and older who is fully vaccinated against COVID-19 is eligible for a booster shot, however a booster is not the same thing as an additional dose. An additional primary dose is administered to people with moderately to severely compromised immune systems. The additional primary dose of an mRNA COVID-19 vaccine is intended to improve immunocompromised people’s response to their vaccine primary series. A booster shot is administered when a person has completed their vaccine primary series to enhance or restore protection against COVID-19 which may have decreased over time.