A study led by the Vall d'Hebron Research Institute (VHIR) shows that paediatric cancer patients do not have a higher risk of severe COVID-19 compared to those without cancer, unless they have received a recent bone marrow transplant or have other underlying diseases. During the pandemic, this study, part of a collaboration between paediatric hospitals in Spain, provided highly relevant data on the management of children and adolescents with cancer and COVID-19. The detailed analysis has now been published in the journal Pediatric Blood & Cancer.

During the pandemic, there was great uncertainty about how to manage infants with cancer infected with SARS-CoV-2: Were they at higher risk of suffering from severe COVID-19 compared to those without cancer? Were more restrictive isolation measures necessary in these cases? Could they continue their treatment with chemotherapy or radiotherapy?

To answer these and other questions, the team coordinated with the COVID-19 working group of the Spanish Society of Paediatric Oncology and Haematology (SEHOP) and the national registry of COVID-19 in infants EPICO-AEP, headed by Dr. Alfredo Tagarro, to create a real-time registry of cases of infants with cancer infected with SARS-CoV-2. The registry was included in the general EPICO-AEP registry, thus facilitating regular analysis of whether children with cancer had a more serious infection than those without the disease, and presenting it at the annual SEHOP meetings to provide guidance on how to manage this infection.

The registry remained open during the health crisis, between 2020 and 2022, and has been analysed by groups from the VHIR, EPICO-AEP and Cruces University Hospital. The results presented in this publication include 256 boys and girls with cancer or a recent bone marrow transplant infected with COVID-19 and 990 children with the infection, but no cancer or transplant.

In general terms, the results reveal that COVID-19 is not an additional risk factor for childhood cancer, but rather the severity is similar in children with and without cancer. However, those who had received an allogeneic stem cell transplant within the previous 300 days or had other additional pathologies showed a significantly higher risk of developing severe COVID-19. It was also observed that all vaccinated patients presented mild COVID-19.

These results were crucial in guiding clinical policy during the COVID-19 health crisis. "We confirmed that there was no need for isolation or treatment measures that differed from other viral infections in cancer patients", says Dr. Pablo Velasco, attending physician at the Paediatric Oncology and Haematology Service of Vall d'Hebron University Hospital, researcher at the Children's Cancer and Haematological Diseases group at VHIR and coordinator of the study. "The work was essential to ensure that crucial treatments such as chemotherapy or radiotherapy were not delayed, unless absolutely necessary, as in other respiratory infections", added Dr. Itziar Astigarraga, head of the Paediatrics Service at Cruces University Hospital and coordinator of the maternal and child health and assisted reproduction research area at the Biobizkaia Institute.

Collaboration and shared data to tackle the health crisis

The researchers used two clinical data platforms to carry out the study: EPICO on COVID-19 in childhood and the registry of the Spanish Society of Paediatric Haematology and Oncology (SEHOP) in childhood cancer. The coordination between the two allowed for a detailed and comparative follow-up of children with and without cancer during the pandemic. “The integration of national and international data and the use of shared registers were key to understanding the true impact of COVID-19 on children with cancer”, says Dr Velasco.

Collaboration between different centres and data exchange with other healthcare workers, through the presentation of the results at various congresses during the crisis, were key factors in applying the results in day-to-day clinical practice. "These results facilitated the immediate management of patients during the pandemic and, moreover, provide a solid basis for clinical management and the formulation of policies in paediatric oncology that better prepares us for future health emergencies", concluded Dr. Velasco.

At Vall d'Hebron, the work was coordinated by the VHIR Cancer and Haematological Diseases group in close collaboration with the Statistics and Bioinformatics Unit (UEB) and the VHIR Infection and Immunity in Paediatric Patients group. In the Basque Country, Susana García Obregón and Olatz Villate Bejarano, researchers from the IIS Biobizkaia children's oncology group, were in charge of analysing the databases and the medical team from the Osakidetza Cruces University Hospital Paediatric Oncology Unit collaborated in collecting cases.