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Coronavirus Vaccines and People with Cancer: A Q&A with Dr. Steven Pergam

, by NCI Staff

Steve Pergam Getting Vaccine

Dr. Steven Pergam of the Fred Hutchinson Cancer Research Center receiving his first dose of a COVID-19 vaccine on December 29, 2020.

Credit: Image courtesy of Dr. Steven Pergam

Many people being treated for cancer are asking whether they should get a COVID-19 vaccine. Steven Pergam, M.D., of the Fred Hutchinson Cancer Research Center in Seattle, was a co-leader of a committee formed by the National Comprehensive Cancer Network (NCCN) that recently developed recommendations on COVID-19 vaccination in cancer patients. In this Q&A, Dr. Pergam discusses some of the questions people with cancer and cancer survivors have about these vaccines.

UPDATED APRIL 9, 2021: NCI’s Cancer Information Service continues to get questions about COVID-19 vaccines from people with cancer and their caregivers. Dr. Pergam has provided answers to some of those questions below. If you have a question that isn’t answered here, click the “Chat Now” button in the box below to connect with an NCI information specialist.

CDC, the NCCN recommendations, and other cancer-related organizations say that cancer patients are a high priority group for vaccination. Why?

We all want to get the vaccines to the people who are at most risk for severe COVID-19 complications, and the data show that cancer patients are high risk. Making highly efficacious vaccines available to those populations is going to be important to saving lives.

Are there any patients undergoing active cancer treatment who should not get vaccinated?

For patients who have just had a stem cell transplant or received CAR T-cell therapy, who are typically receiving immunosuppressive therapy, we recommend that they delay COVID-19 vaccination until at least 3 months after they’ve completed treatment. That’s based on data that [other] vaccines have had limited efficacy during periods when these patients are their most immunosuppressed.

The data are a little less clear for patients who are getting aggressive chemotherapy, but for those who are receiving more intensive treatment regimens—for example, those starting initial therapy for leukemia—we recommend that they delay vaccination until their cell counts recover.

Those are the two main groups where I think there is agreement that they should delay COVID-19 vaccination, at least initially.

Will receiving the vaccine during cancer treatment make the cancer treatment less effective?

No. There is no evidence that any vaccines make cancer therapy less effective. If anything, the opposite is true: cancer therapy may make vaccine responses less robust.

And survivors, those not undergoing active cancer treatment. Are there any reasons they shouldn’t get vaccinated?

I think that depends on when you ask the question. How much vaccine do you have [available]? If you have unlimited amounts, then everybody should get vaccinated. But when you get into vaccine allocation issues, that’s when it gets challenging.

But there’s no question that many cancer survivors have immunologic deficiencies, so I see many of them as being at high risk. Cancer survivors are also people who tend to be older and have other comorbidities—heart disease, kidney or lung dysfunction—so they’re going to have other reasons that will put them at risk for developing severe COVID-19, and those are all reasons for them to get vaccinated.

And what about those who may be undergoing treatment soon, such as somebody just diagnosed with cancer or whose treatment has been delayed by the pandemic?

The approach we discussed in the NCCN committee is that we really don’t want to create guidance that will prevent cancer patients from getting vaccinated. If you start trying to nuance it for the “right time,” it may mean that many patients won’t get the vaccine. So, the best approach is to get the vaccine when you can.

Still, there are some caveats. We do recommend delays for patients undergoing stem cell transplant and those getting induction therapy for leukemia. In addition, cancer patients who are about to undergo surgery should probably wait for a week until after surgery to get vaccinated. Because we don’t want any potential side effects from the vaccine—for example, a fever—to potentially delay their surgery.

So, there are some specific exceptions, but we tried to limit restrictions.

Can getting vaccinated cause a rise in tumor markers or signs of cancer recurrence just after a vaccination?

I am not aware of any evidence that suggests vaccines can affect cancer biomarkers in this way. However, we do know that the Pfizer and Moderna vaccines can lead to enlarged lymph nodes, particularly those in your armpit, called axillary lymph nodes. Developing new swelling in the armpit of your vaccinated arm a few days after getting your shot likely means the vaccine is producing a good immune response.

Some recently vaccinated people who have had imaging scans have had these lymph nodes “light up,” so our committee recommends talking to your cancer care team about any upcoming scans to make sure that they are aware of your recent vaccine. They may want to delay your scan unless it is urgent.

If you do get swelling after being vaccinated, and it doesn’t go away after about a week, make sure to tell your doctor.

I have lymphedema from lymph node surgery in one of my arms. Can I still get the shot in that arm?

Patients with lymphedema or those who have had a lymph node dissection in one arm, say for treatment of breast cancer, should get vaccinated in the other arm. Patients with lymphedema are at increased risk of infection and should avoid vaccinations in the affected arm.

If you have lymphedema in both arms, then the thigh can also be used as an alternate site for vaccine injection. In either case, if you have any lymphedema or have had a lymph node dissection, make sure you tell the personnel working at the vaccination site and they can vaccinate you in your other arm.

Is one COVID-19 vaccine better than another for people with cancer/cancer survivors?

These vaccines have not been studied head to head in clinical trials. People with cancer should take whichever vaccine they are offered first. The key is to get vaccinated, so sign up for an appointment, roll up your sleeve, and get your vaccine.

Are researchers collecting data on how effective the vaccines are in people with cancer?

A number of research groups are interested in vaccine efficacy in people with cancer, from those with solid tumors to those receiving bone marrow transplants. For example, there are researchers looking at people who have blood cancers, like CLL or CML, because they are more likely to have immunodeficiency over a long period of time. Every cancer doctor wants to know the answer to the question: How do my patients respond to these vaccines?

There will be lots of analyses that will need to be done. I want to see studies of how well the vaccines work in people with specific cancers, as well as in those who receive specific chemotherapies or treatment regimens.

Is there any indication that current patients or survivors will have less protection from a COVID-19 vaccine?

Much of these data don’t exist yet for COVID vaccines, but from prior studies with other vaccines we can assume that COVID vaccines will likely not be as effective in some people with cancer compared with others—in particular, patients with blood cancers (such as leukemia and lymphoma) or those receiving aggressive chemotherapy that weakens their immune systems.

The expectation is that most patients will respond to the vaccine. But, based on the data from other vaccines, I think it’s highly likely that they're not going to see the 95% protection we’re seeing against symptomatic COVID-19 disease [from the Pfizer and Moderna vaccines] in the general public. I think it will be less than that. But even if it’s 50%, it’s still going to be a major benefit.

So, the CDC recommends that all people who are vaccinated continue to wear masks in public settings. Prevention remains important for people with cancer who are vaccinated, particularly those who are getting chemotherapy or radiation (and those with other health conditions). We recommend that they continue to wear masks, remain socially distant when possible, and avoid large get-togethers and crowds.

And, similar to the flu vaccine, preventing infection is not the only aim of COVID-19 vaccines; it’s also preventing the complications of infection. Existing COVID-19 vaccines may not prevent the primary infection, but we hope that they can prevent cancer patients from developing severe COVID-19 disease or hospitalization, as has been seen in the phase 3 trials among the general public. There could be other downstream benefits that could also be very helpful.

What about caregivers of those with cancer? Should they be a priority group for vaccination?

This is an underappreciated question. There’s no doubt that if you think about a vaccine strategy, if we assume that people with cancer aren’t going to respond as well to the COVID-19 vaccine, one of the best ways to protect them is to give the vaccine to people who will respond well. And that means anybody who they spend time with. So, anybody who is a caregiver, a loved one, or is in close contact with somebody with cancer, it’s important for them to get vaccinated.

Because the thought is that, first, it will decrease the caregiver’s risk of developing symptomatic infections and data suggest that symptomatic people are more likely to transmit the virus to people around them.

And, two, we hope that available vaccines may prevent transmission—although available studies evaluating this question are ongoing. If true, then caregivers and loved ones getting vaccinated will really help. Because that cocooning effect, vaccinating the close contacts around people with cancer, can provide extra protection.

NCI information specialists are available to help answer your questions about coronavirus and cancer Monday through Friday 9:00 a.m.–9:00 p.m. ET.

Is there any indication that people with cancer/cancer survivors are choosing not to get vaccinated?

That’s hard to know right now. Cancer patients are just starting to get these vaccines, due to challenges in the supply chain. I think some cancer patients will be hesitant, but not necessarily more so than the general population. We hope that they are more accepting of vaccines because they know they’re at risk [of severe COVID].

I can say that locally, in [Seattle-area] institutions, cancer patients are clamoring to get the vaccine. Physicians are feeling challenged because they’re getting so many calls from their patients to ask when it will be available and when can they get it. The patients know the risk, and they see it as an opportunity to protect themselves. That’s great to see, and I hope it continues.

How do you see the approach to vaccination changing over the coming months?

One thing for people to be aware of is that the guidance around the COVID-19 vaccines is going to change over time. And that’s for a couple of reasons. One, because more data will become available. Even if they’re small studies, they can be very informative. Two, there are already more vaccines. The Janssen/Johnson & Johnson vaccine is now available to the public, and [other] vaccines are also possibly going to become available in the US.

We expect that other vaccines will allow more people to get vaccinated. But there may be one or two vaccines that will be better for cancer patients, so we’ll need to see more data. I really want to see NCI and NIH and other funding agencies support these types of studies. It is critical to choose the vaccines with the highest efficacy in cancer patients and to help us decide who should be vaccinated and when—and if they need additional booster shots to help protect them.

We’re just beginning to think about trials that can be pragmatic and useful for providers—to best understand how to protect patients. That is going to be very important as we continue to address the pandemic and protect patients against SARS-CoV-2 in the future.