A recent study published in JAMA Oncology has shown that patients with cancer have an increased risk for COVID-19 infection after being vaccinated for COVID-19 (called breakthrough infections) and worse outcomes. The patients at highest risk are those with blood cancer.

The study was carried out at the University of Toronto and Sunnybrook Health Sciences Centre in Canada. The researchers were looking at breakthrough infections following COVID-19 vaccination and complications in people with cancer compared to people without cancer. There were 289,400 vaccinated cancer patients in the study, 39,880 of which had blood cancer and 249,520 had solid cancer. These people were compared with 1,157,600 people without cancer but with similar characteristics (age, sex, weight, height, health etc.).

Compared to the people without cancer, the researchers found that patients with blood cancer had an increased risk for COVID-19 breakthrough infections, but patients with solid cancer, such as kidney cancer, did not.

Severe outcomes of COVID-19 infection (hospitalisation and death) were significantly higher in people with cancer compared to those without cancer. The risk for severe outcomes was higher for patients with blood cancer compared to solid cancer, such as kidney cancer. The risk of severe outcomes for COVID-19 infection was worse for patients receiving active treatment, especially anti-CD20 therapy (which is not used for kidney cancer).

For those cancer patients who had been given a third (booster) vaccination, there was less COVID-19 breakthrough infections and health complications.

This study supports prioritisation of high-risk people for booster vaccinations, forthcoming vaccinations against new variants of the coronavirus, and rapid COVID-19 treatment for those cancer patients who catch the virus.

Read more in Practice Update here