SickKids and ICES-led research illustrates risk of COVID-19 for childhood cancer survivors

Survivors of childhood and adolescent and young adult (AYA) cancer were at no increased risk of COVID-19 infection or subsequent hospitalization, ICU admission or death during the first 18 months of the pandemic, according to a new study led by researchers at The Hospital for Sick Children (SickKids) and ICES.

The study, published on February 28 in the Journal of Clinical Oncology, showed that from January 1, 2020 to May 31, 2021, childhood and AYA cancer survivors’ rates of COVID-19 infection or subsequent hospitalization in Ontario were no different than other people of the same age or demographics.

“These are reassuring results which I hope will be welcome news for survivors of childhood and AYA cancer and their families,” says Dr. Sumit Gupta, lead author of the study, Staff Oncologist in the Division of Haematology/Oncology and Associate Scientist, Child Health Evaluative Sciences at SickKids and Scientist at ICES. “Patients who were childhood or AYA cancer survivors had no increased risk of getting a positive COVID-19 test.”

Not only that, Gupta, who is also an Associate Professor in the Department of Paediatrics and Institute for Health Policy, Management and Evaluation at University of Toronto, says the study also showed that survivors who did have a positive COVID-19 test also had no increased risk of hospitalization, ICU admission or death relative to their peers with positive tests. He explains that although the risk of hospitalization for COVID-19 stood at about two per cent for both the survivor group and their control population counterparts, “no childhood or AYA cancer survivor who tested positive during the timeframe we looked at was subsequently admitted to the ICU or died.”

Research offers ‘reassurance’ to childhood and AYA cancer survivors and their families amid the COVID-19 pandemic

The research is the first population-based study to look at the rates of COVID-19 infection in survivors of childhood and AYA cancers. The researchers followed more than 12,000 cancer survivors throughout the pandemic, most of whom were between the ages of 16 and 32 years old and were five years out from their cancer diagnosis. Using Ontario health services data from ICES, they compared them to a cancer-free control population made up of more than 124,000 people of similar age, sex and geographic location. 

Gupta says that while COVID-19 is a serious disease, these data suggest it is no more serious for younger childhood and AYA cancer survivors than for the general population. He hopes that this study can help to alleviate a source of anxiety for these patients and their families amid the pandemic.

For many survivors of childhood and AYA cancer, late effects and comorbidities as a result of their cancer diagnosis or treatment are common. They can include diabetes, congestive heart failure, lung disease and adverse outcomes related to infections, which are typically risk factors for severe COVID-19 infection.

“When you put that all together, it’s understandable why survivors, their families and their care providers would worry about their risk being heightened during the COVID-19 pandemic,” says Gupta.

Childhood and AYA cancer survivors also experience higher rates of anxiety and mental health challenges long after undergoing cancer treatment, which can contribute to poor outcomes related to their education and employment. Over the course of the pandemic, other studies have suggested that as many as 70 per cent of childhood and AYA cancer survivors felt that they were at a heightened risk of adverse outcomes related to a COVID-19 infection, which, Gupta says, has resulted in greater anxiety and school and work-related avoidance.

Gupta notes that while cancer survivors were not a priority group to receive the COVID-19 vaccine when it was first approved in late 2020, childhood and AYA cancer survivors were more likely to be fully vaccinated than their peers once the COVID-19 vaccine was made available to them.

Through the data that Gupta and his team present in the study, he hopes to ease some of the anxiety that childhood and AYA cancer survivors have felt over the past two years.

“Survivors are weighing their risks of many in-person activities, like going back to school or work. It’s my hope that these individuals can take these data and say, ‘my risk doesn’t seem to be any better or worse than that of anyone else,’” says Gupta, who adds that individuals should speak to their doctor or health-care support team about making decisions that are right for them.

“Everyone is going to make their own decisions based on their own risk tolerance, but it’s important that people have the most accurate data possible to quantify that risk to make their own decisions.”

Gupta notes that the study took place prior to the COVID-19 waves driven by the Delta and Omicron variants. Although the data is not generalizable to infections with these variants, he says, “our data does suggest that the risk profile of childhood cancer survivors and the general population may be more similar than a lot of people have thought.”

An additional limitation of the study was that it did not examine rates of Long COVID among cancer survivors, for which population-based data is limited. The study also did not examine the impact of COVID-19 on children, adolescents or young adults currently undergoing cancer treatment or older cancer survivors, who could still be at a higher risk of severe outcomes related to COVID-19. The study points out that it is not clear whether the age of childhood and AYA cancer survivors studied is a factor.

“The data, despite the limitations, are useful to allow survivors and their family members to properly assess their risk and make whatever decisions they are comfortable with,” says Gupta.

This research was supported by ICES, the Pediatric Oncology Group of Ontario and SickKids Foundation.