Many expert medical groups now recommend that most people with cancer or a history of cancer get the COVID-19 vaccine once it’s available to them.
The main concern about getting the vaccine is not whether it’s safe for people with cancer, but about how effective it will be, especially in people with weakened immune systems. Some cancer treatments like chemotherapy (chemo), radiation, stem cell or bone marrow transplant, or immunotherapy can affect the immune system, which might make the vaccine less effective.
The initial studies testing the COVID-19 vaccines did not include people getting treatment with drugs that suppress the immune system, like chemo, or people who have weakened immune systems for other reasons. This is because the studies needed to see first if the vaccines work in people with healthy immune systems. Because of this, it’s not yet clear how effective the vaccines might be in these groups of people.
Although we don’t have specific information yet on how effective the vaccines might be in people being treated for cancer, it’s possible that the vaccines might not be as effective in people with weakened immune systems as compared to people with healthy immune systems. Despite this, experts still recommend that most cancer patients get the vaccine because those with a fragile immune system are at risk for severe COVID-19 disease, so getting even some protection from the vaccine is better than not having any protection.