According to research presented at the NCRI festival, children with kidney cancer are still diagnosed with larger and more advanced tumors in the UK and Ireland than in other Western European countries.
As a result, a leading pediatric cancer expert has called for all staff providing primary health care for children in the UK’s National Health Service (NHS) to be trained in pediatrics to help detect diseases such as kidney cancer earlier.
Ms Reem Al-Saadi, senior translational research manager at UCL Great Ormond Street Institute of Child Health, University College London, UK, presented the findings of the first study to systematically look at how children are diagnosed with kidney cancer in the UK.
Reporting on 603 of 712 children registered with kidney cancer between 2012 and 2018 from 20 treatment centers in the UK and Ireland (approximately 90% of all children with kidney cancer in these countries), she said 86% had a Wilms tumor (the most common childhood kidney cancer) and 14% had non-Wilms kidney tumors. Computerized tomography (CT) and magnetic resonance imaging (MRI) scans that create detailed images of the inside of the body were reviewed centrally as part of the studies to ensure consistency of diagnosis.
“We found that spread of the kidney cancer to the lungs was detected in 24% of the children; this was definitive in 18% and only detected by the CT scan in 6%, meaning the nodules were so small that there is uncertainty about whether they are carcinogenic or not,” she said.
“The majority of children were not diagnosed until they began to show symptoms: 77% had symptoms specific to tumors at diagnosis, such as abdominal mass, abdominal pain, or blood in the urine; 16% had nonspecific symptoms; 5% were diagnosed as a result of genetic screening and 2% as a result of a child health check, which means that only a few cancers are picked up incidentally before symptoms start to show.”
The mean (median) size of tumors was 547 ml in volume, with a quarter being larger than 901 ml.
The tumor volumes we saw did not differ significantly from an analysis of children diagnosed in 2002-2011, when tumor volumes were found to be greater than those at diagnosis in Germany. The median volume at the time was 572 ml in the UK compared to 382 ml in Germany.”
Ms Reem Al-Saadi, Senior Translational Research Manager at UCL Great Ormond Street Institute of Child Health, University College London, UK
The findings come from the IMPORT (Improving Populations Outcome of Renal Tumors of child) study, which has since expanded to include international research groups and became the UMBRELLA study. With the exception of the work in Germany, it is the only initiative in the world that collects standardized data on the route to diagnosis of a child with kidney cancer.
Kathy Pritchard-Jones, professor of pediatric oncology at the Great Ormond Street Institute of Child Health, is principal investigator of the IMPORT and UMBRELLA studies. Speaking to the NCRI festival, she said: “We only have very early comparative data for about 1,000 cases diagnosed as of 2019, but this early analysis of the UMBRELLA study found that 75% of children in the UK and Ireland were diagnosed tumor-related symptoms, which are higher than in most other European countries. This confirms similar findings from an international study conducted between 2001 and 2011.”
She continued: “We know that in European countries where children have smaller tumors at diagnosis, primary care is provided by trained pediatricians who work in the community. They are more likely to fully examine a child if they come in with vague symptoms and therefore have more chance to pick up that something is not quite right in the belly.
“Efforts are needed to achieve an earlier diagnosis of childhood kidney cancer to improve survival rates in the UK and Ireland. We believe that primary care for children should be provided by staff trained in pediatrics. Cancer is part of a broader problem of late diagnosis of serious childhood illness in the UK, which has been highlighted by the Royal College of Pediatrics and Child Health.”
The findings reported today include two years of follow-up of the children after 2018. During this time, 78 (13%) relapsed and 44 (7%) died.
Prof Pritchard-Jones said: “The treatments have not changed in the last decade, and we expect that the UMBRELLA trial will keep overall survival rates comparable at just over 90%. The study will allow us to make international comparisons to to see how the UK is performing in the early diagnosis and treatment of children with abdominal tumors, and it will help us monitor improvements.”
Kidney cancer in children is a rare disease. The Wilms tumor is diagnosed in about 87 children in the UK each year. Treatment is one of the childhood cancer success stories of recent years, with more than 90% of children surviving. However, there are some subgroups that have a poor outcome, with their cancer returning and in some cases dying. Early diagnosis before cancer starts to spread, coupled with improved treatments, can help improve outcomes in these children.
Prof Pritchard-Jones and colleagues are exploring ways to personalize treatment for each child based on biological cues that can be used to determine the intensity of treatment needed. They are also testing the use of artificial intelligence to assess the nodules seen in CT scans for their potential for cancer that has spread (metastasized) from the primary tumor.
Richard Neal, member of the NCRI Screening, Prevention and Early Diagnosis (SPED) Group and Professor of Primary Care at the University of Exeter, UK, who was not involved in the study, said: “It is disappointing to see very little progress over the past 20 years in diagnosing this disease at an earlier stage, when the tumors are smaller and easier to treat successfully, this work also shows how difficult it is to pick up these tumors at an early stage. additional challenges are in diagnosis due to the COVID-19 pandemic, with fewer patients, including children, being seen and physically examined in person. We urgently need work to explore what interventions could work to improve the situation.”
National Institute of Cancer Research